Charge Trapping and Defect Dynamics as Origin of Memory Effects in Metal Halide Perovskite Memlumors

Large language models for artificial intelligence applications require energy-efficient computing. Neuromorphic photonics has the potential to reach significantly lower energy consumption in comparison with classical electronics. A recently proposed memlumor device uses photoluminescence output that carries information about its excitation history via the excited state dynamics of the material. Solution-processed metal halide perovskites can be used as efficient memlumors. We show that trapping of photogenerated charge carriers modulated by photoinduced dynamics of the trapping states themselves explains the memory response of perovskite memlumors on time scales from nanoseconds to minutes. The memlumor concept shifts the paradigm of the detrimental role of charge traps and their dynamics in metal halide perovskite semiconductors by enabling new applications based on these trap states. The appropriate control of defect dynamics in perovskites allows these materials to enter the field of energy-efficient photonic neuromorphic computing, which we illustrate by proposing several possible realizations of such systems.

Processing polymer photocatalysts for photocatalytic hydrogen evolution

Conjugated materials have emerged as competitive photocatalysts for the production of sustainable hydrogen from water over the last decade. Interest in these polymer photocatalysts stems from the relative ease to tune their electronic properties through molecular engineering, and their potentially low cost. However, most polymer photocatalysts have only been utilised in rudimentary suspension-based photocatalytic reactors, which are not scalable as these systems can suffer from significant optical losses and often require constant agitation to maintain the suspension. Here, we will explore research performed to utilise polymeric photocatalysts in more sophisticated systems, such as films or as nanoparticulate suspensions, which can enhance photocatalytic performance or act as a demonstration of how the polymer can be scaled for real-world applications. We will also discuss how the systems were prepared and consider both the benefits and drawbacks of each system before concluding with an outlook on the field of processable polymer photocatalysts.

Tuning Charge-Transfer States by Interface Electric Fields

Intermolecular charge-transfer (CT) states are extended excitons with a charge separation on the nanometer scale. Through absorption and emission processes, they couple to the ground state. This property is employed both in light-emitting and light-absorbing devices. Their conception often relies on donor-acceptor (D-A) interfaces, so-called type-II heterojunctions, which usually generate significant electric fields. Several recent studies claim that these fields alter the energetic configuration of the CT states at the interface, an idea holding prospects like multicolor emission from a single emissive interface or shifting the absorption characteristics of a photodetector. Here, we test this hypothesis and contribute to the discussion by presenting a new model system. Through the fabrication of planar organic p-(i-)n junctions, we generate an ensemble of oriented CT states that allows the systematic assessment of electric field impacts. By increasing the thickness of the intrinsic layer at the D-A interface from 0 to 20 nm and by applying external voltages up to 6 V, we realize two different scenarios that controllably tune the intrinsic and extrinsic electric interface fields. By this, we obtain significant shifts of the CT-state peak emission of about 0.5 eV (170 nm from red to green color) from the same D-A material combination. This effect can be explained in a classical electrostatic picture, as the interface electric field alters the potential energy of the electric CT-state dipole. This study illustrates that CT-state energies can be tuned significantly if their electric dipoles are aligned to the interface electric field.

Confinement Effects on Proton Transfer in TiO2 Nanopores from Machine Learning Potential Molecular Dynamics Simulations

Improved understanding of proton transfer in nanopores is critical for a wide range of emerging applications, yet experimentally probing mechanisms and energetics of this process remains a significant challenge. To help reveal details of this process, we developed and applied a machine learning potential derived from first-principles calculations to examine water reactivity and proton transfer in TiO2 slit-pores. We find that confinement of water within pores smaller than 0.5 nm imposes strong and complex effects on water reactivity and proton transfer. Although the proton transfer mechanism is similar to that at a TiO2 interface with bulk water, confinement reduces the activation energy of this process, leading to more frequent proton transfer events. This enhanced proton transfer stems from the contraction of oxygen-oxygen distances dictated by the interplay between confinement and hydrophilic interactions. Our simulations also highlight the importance of the surface topology, where faster proton transport is found in the direction where a unique arrangement of surface oxygens enables the formation of an ordered water chain. In a broader context, our study demonstrates that proton transfer in hydrophilic nanopores can be enhanced by controlling pore size, surface chemistry, and topology.

Dark Current in Broadband Perovskite-Organic Heterojunction Photodetectors Controlled by Interfacial Energy Band Offset

Lead halide perovskite and organic semiconductors are promising classes of materials for photodetector (PD) applications. State-of-the-art perovskite PDs have performance metrics exceeding silicon PDs in the visible. While organic semiconductors offer bandgap tunability due to their chemical design with detection extended into the near-infrared (NIR), perovskites are limited to the visible band and the first fraction of the NIR spectrum. In this work, perovskite-organic heterojunction (POH) PDs with absorption up to 950 nm are designed by the dual contribution of perovskite and the donor:acceptor bulk-heterojunction (BHJ), without any intermediate layer. The effect of the energetics of the donor materials is systematically studied on the dark current (Jd) of the device by using the PBDB-T polymer family. Combining the experimental results with drift-diffusion simulations, it is shown that Jd in POH devices is limited by thermal generation via deep trap states in the BHJ. Thus, the best performance is obtained for the PM7-based POH, which delivers an ultra-low noise current of 2 × 10-14 A Hz-1/2 and high specific detectivity of 4.7 × 1012 Jones in the NIR. Last, the application of the PM7-based POH devices as NIR pulse oximeter with high-accuracy heartbeat monitoring at long-distance of 2 meters is demonstrated.

Charging the Future: Harnessing Nature's Designs for Bioinspired Molecular Electrodes

The transition toward electric-powered devices is anticipated to play a pivotal role in advancing the global net-zero carbon emission agenda aimed at mitigating greenhouse effects. This shift necessitates a parallel focus on the development of energy storage materials capable of supporting intermittent renewable energy sources. While lithium-ion batteries, featuring inorganic electrode materials, exhibit desirable electrochemical characteristics for energy storage and transport, concerns about the toxicity and ethical implications associated with mining transition metals in their electrodes have prompted a search for environmentally safe alternatives. Organic electrodes have emerged as promising and sustainable alternatives for batteries. This review paper will delve into the recent advancements in nature-inspired electrode design aimed at addressing critical challenges such as capacity degradation due to dissolution, low operating voltages, and the intricate molecular-level processes governing macroscopic electrochemical properties.

Rb-Doped Perovskite Oxides: Surface Enrichment and Structural Reconstruction During the Oxygen Evolution Reaction

Alkali-metal doped perovskite oxides have emerged as promising materials due to their unique properties and broad applications in various fields, including photovoltaics and catalysis. Understanding the complex interplay between alkali metal doping, structural modifications, and their impact on performance remains a crucial challenge. In this study, this challenge is addressed by investigating the synthesis and properties of Rb-doped perovskite oxides. These results reveal that the doping of Rb into perovskite oxides function as a structural modifier in the as-synthesized samples and during the oxygen evolution reaction (OER) as well. Electron microscopy and first-principles calculations confirm the enrichment of Rb on the surface of the as-synthesized sample. Further investigations into the electrocatalytic reaction revealed that the Rb-doped perovskite underwent drastic restructuring with Rb leaching and formation of strontium oxide.

Lithium salt of a pro-mesogenic [closo-CB11H12]- derivative: anisotropic Li+ ion transport in liquid crystalline electrolytes

Li+ ion conduction in two aligned liquid crystalline electrolytes consisting of 10 mol% Li+ salt of a pro-mesogenic anion derived from [closo-1-CB11H12]- in non-ionic hosts was investigated. Using electrochemical impedance spectroscopy (EIS), the ionic conductivity in the parallel (σ‖) and perpendicular (σ⊥) directions of the electrolyte samples was determined using two types of cells: an interdigitated gold electrode and a nylon 6-coated ITO cell. The ratio of ionic conductivities σ⊥/σ‖ in the electrolyte with a nona(ethylene oxide) spacer was about 3 in the entire SmA phase, while in the shorter homologue, the ratio monotonically increases from about 0.4 to 2.9. The liquid crystalline behavior of the hosts and the electrolytes was investigated by optical, thermal, and powder XRD methods.

Enabling High-Performance Battery Electrodes by Surface-Structuring of Current Collectors and Crack Formation in Electrodes: A Proof-of-Concept

Today's society and economy demand high-performance energy storage systems with large battery capacities and super-fast charging. However, a common problematic consequence is the delamination of the mass loading (including, active materials, binder and conductive carbon) from the current collector at high C-rates and also after certain cycle tests. In this work, surface structuring of aluminum (Al) foils (as a current collector) is developed to overcome the aforementioned delamination process for sulfur (S)/carbon composite cathodes of Li-S batteries (LSBs). The structuring process allows a mechanical interlocking of the loaded mass with the structured current collector, thus increasing its electrode adhesion and its general stability. Through directed crack formation within the mass loading, this also allows an enhanced electrolyte wetting in deeper layers, which in turn improves ion transport at increased areal loadings. Moreover, the interfacial resistance of this composite is reduced leading to an improved battery performance. In addition, surface structuring improves the wettability of water-based pastes, eliminating the need for additional primer coatings and simplifying the electrode fabrication process. Compared to the cells made with untreated current collectors, the cells made with structured current collectors significantly improved rate capability and cycling stability with a capacity of over 1000mAhg-1. At the same time, the concept of mechanical interlocking offers the potential of transfer to other battery and supercapacitor electrodes.

Strain Heterogeneity and Extended Defects in Halide Perovskite Devices

Strain is an important property in halide perovskite semiconductors used for optoelectronic applications because of its ability to influence device efficiency and stability. However, descriptions of strain in these materials are generally limited to bulk averages of bare films, which miss important property-determining heterogeneities that occur on the nanoscale and at interfaces in multilayer device stacks. Here, we present three-dimensional nanoscale strain mapping using Bragg coherent diffraction imaging of individual grains in Cs0.1FA0.9Pb(I0.95Br0.05)3 and Cs0.15FA0.85SnI3 (FA = formamidinium) halide perovskite absorbers buried in full solar cell devices. We discover large local strains and striking intragrain and grain-to-grain strain heterogeneity, identifying distinct islands of tensile and compressive strain inside grains. Additionally, we directly image dislocations with surprising regularity in Cs0.15FA0.85SnI3 grains and find evidence for dislocation-induced antiphase boundary formation. Our results shine a rare light on the nanoscale strains in these materials in their technologically relevant device setting.

Two-dimensional perovskite templates for durable, efficient formamidinium perovskite solar cells

We present a design strategy for fabricating ultrastable phase-pure films of formamidinium lead iodide (FAPbI3) by lattice templating using specific two-dimensional (2D) perovskites with FA as the cage cation. When a pure FAPbI3 precursor solution is brought in contact with the 2D perovskite, the black phase forms preferentially at 100°C, much lower than the standard FAPbI3 annealing temperature of 150°C. X-ray diffraction and optical spectroscopy suggest that the resulting FAPbI3 film compresses slightly to acquire the (011) interplanar distances of the 2D perovskite seed. The 2D-templated bulk FAPbI3 films exhibited an efficiency of 24.1% in a p-i-n architecture with 0.5-square centimeter active area and an exceptional durability, retaining 97% of their initial efficiency after 1000 hours under 85°C and maximum power point tracking.

The Effect of Cesium Incorporation on the Vibrational and Elastic Properties of Methylammonium Lead Chloride Perovskite Single Crystals

Hybrid organic-inorganic lead halide perovskites (LHPs) have emerged as a highly significant class of materials due to their tunable and adaptable properties, which make them suitable for a wide range of applications. One of the strategies for tuning and optimizing LHP-based devices is the substitution of cations and/or anions in LHPs. The impact of Cs substitution at the A site on the structural, vibrational, and elastic properties of MAxCs1-xPbCl3-mixed single crystals was investigated using X-ray diffraction (XRD) and Raman and Brillouin light scattering techniques. The XRD results confirmed the successful synthesis of impurity-free single crystals, which exhibited a phase coexistence of dominant cubic and minor orthorhombic symmetries. Raman spectroscopy was used to analyze the vibrational modes associated with the PbCl6 octahedra and the A-site cation movements, thereby revealing the influence of cesium incorporation on the lattice dynamics. Brillouin spectroscopy was employed to investigate the changes in elastic properties resulting from the Cs substitution. The incorporation of Cs cations induced lattice distortions within the inorganic framework, disrupting the hydrogen bonding between the MA cations and PbCl6 octahedra, which in turn affected the elastic constants and the sound velocities. The substitution of the MA cations with smaller Cs cations resulted in a stiffer lattice structure, with the two elastic constants increasing up to a Cs content of 30%. The current findings facilitate a fundamental understanding of mixed lead chloride perovskite materials, providing valuable insights into their structural and vibrational properties.

Pourbaix Machine Learning Framework Identifies Acidic Water Oxidation Catalysts Exhibiting Suppressed Ruthenium Dissolution

The demand for green hydrogen has raised concerns over the availability of iridium used in oxygen evolution reaction catalysts. We identify catalysts with the aid of a machine learning-aided computational pipeline trained on more than 36,000 mixed metal oxides. The pipeline accurately predicts Pourbaix decomposition energy (Gpbx) from unrelaxed structures with a mean absolute error of 77 meV per atom, enabling us to screen 2070 new metallic oxides with respect to their prospective stability under acidic conditions. The search identifies Ru0.6Cr0.2Ti0.2O2 as a candidate having the promise of increased durability: experimentally, we find that it provides an overpotential of 267 mV at 100 mA cm-2 and that it operates at this current density for over 200 h and exhibits a rate of overpotential increase of 25 μV h-1. Surface density functional theory calculations reveal that Ti increases metal-oxygen covalency, a potential route to increased stability, while Cr lowers the energy barrier of the HOO* formation rate-determining step, increasing activity compared to RuO2 and reducing overpotential by 40 mV at 100 mA cm-2 while maintaining stability. In situ X-ray absorption spectroscopy and ex situ ptychography-scanning transmission X-ray microscopy show the evolution of a metastable structure during the reaction, slowing Ru mass dissolution by 20× and suppressing lattice oxygen participation by >60% compared to RuO2.

Cellulose-based thermoelectric composites: A review on mechanism, strategies and applications

The ever-increasing demand for energy and environmental concerns have driven scientists to look for renewable and eco-friendly alternatives. Bio-based thermoelectric (TE) composite materials provide a promising solution to alleviate the global energy crisis due to their direct conversion of heat to electricity. Cellulose, the most abundant bio-polymer on earth with fascinating structure and desirable physicochemical properties, provides an excellent alternative matrix for TE materials. Here, recent studies on cellulose-based TE composites are comprehensively summarized. The fundamentals of TE materials, including TE effects, TE devices, and evaluation on conversion efficiency of TE materials are briefly introduced at the beginning. Then, the state-of-the-art methods for constructing cellulose-based TE composites in the forms of paper/film, aerogel, liquid, and hydrogel, are highlighted. TE performances of these composites are also compared. Following that, applications of cellulose-based TE composites in the fields of energy storage (e.g., supercapacitors) and sensing (e.g., self-powered sensors) are presented. Finally, opportunities and challenges that need investigation toward further development of cellulose-based TE composites are discussed.

Comparative Analysis of the Stability and Performance of Double-, Triple-, and Quadruple-Cation Perovskite Solar Cells for Rooftop and Indoor Applications

The solar energy market is predicted to be shared between Si solar cells and third-generation photovoltaics in the future. Perovskite solar cells (PSCs) show the greatest potential to capture a share there as a single junction or in tandem with silicon. Researchers worldwide are looking to optimize the composition of the perovskite film to achieve an optimal bandgap, performance, and stability. Traditional perovskites have a mixture of formamidinium and methyl ammonium as the A-site cation in their ABX3 structure. However, in recent times, the use of cesium and rubidium has become popular for making highly efficient PSCs. A thorough analysis of the performance and stability of double-, triple-, and quadruple-cation PSCs under different environmental conditions was performed in this study. The performance of the device and the films was analyzed by electrical measurements (J-V, dark J-V, EQE), scanning electron microscopy, atomic force microscopy, photoluminescence, and X-ray diffraction. The quadruple-cation device with the formula Cs0.07Rb0.03FA0.77MA0.13PbI2.8Br0.2 showed the highest power conversion efficiency (PCE) of 21.7%. However, this device had the least stability under all conditions. The triple-cation device with the formula Cs0.1FA0.6MA0.3PbI2.8Br0.2, with a slightly lower PCE (21.2%), was considerably more stable, resulting in about 30% more energy harvested than that using the other two devices during their life cycle.

Multiple Stabilization Effects of Benzylhydrazine on Scalable Perovskite Precursor Inks for Improved Perovskite Solar Cell Production

Perovskite precursor inks suffer various forms of degradation, such as iodide anion oxidation and organic cation breakdown, hindering reliable perovskite solar cell manufacturing. Here we report that benzylhydrazine hydrochloride (BHC) not only retards the buildup of iodine as previously reported but also prevents the breakdown of organic cations. Through investigating BHC and iodine chemical reactions, we elucidate protonation and dehydration mechanisms, converting BHC to harmless volatile compounds, thus preserving perovskite film crystallization and solar cell performance. This inhibition effect lasts nearly a month with minimal BHC, contrasting control inks without BHC where organic cations fully react in less than a week. This enhanced understanding, from additive stabilization to end products, promises improved perovskite solar cell production reliability.

Operando Spectroscopic Monitoring of Metal Chalcogenides for Overall Water Splitting: New Views of Active Species and Sites

Metal-based chalcogenides exhibit great promise for overall water splitting, yet their intrinsic catalytic reaction mechanisms remain to be fully understood. In this work, we employed operando X-ray absorption (XAS) and in situ Raman spectroscopy to elucidate the structure-activity relationships of low-crystalline cobalt sulfide (L-CoS) catalysts toward overall water splitting. The operando results for L-CoS catalyzing the alkaline hydrogen evolution reaction (HER) demonstrate that the cobalt centers in the bulk are predominantly coordinated by sulfur atoms, which undergo a kinetic structural rearrangement to generate metallic cobalt in S-Co-Co-S moieties as the true catalytically active species. In comparison, during the acidic HER, L-CoS undergoes local structural optimization of Co centers, and H2 production proceeds with adsorption/desorption of key intermediates atop the Co-S-Co configurations. Further operando characterizations highlight the crucial formation of high-valent Co4+ species in L-CoS for the alkaline oxygen evolution reaction (OER), and the formation of such active species was found to be far more facile than in crystalline Co3O4 and Co-LDH references. These insights offer a clear picture of the complexity of active species and site formation in different media, and demonstrate how their restructuring influences the catalytic activity.

Design Principles of Quinone Redox Systems for Advanced Sulfide Solid-State Organic Lithium Metal Batteries

The emergence of solid-state battery technology presents a potential solution to the dissolution challenges of high-capacity small molecule quinone redox systems. Nonetheless, the successful integration of argyrodite-type Li6PS5Cl, the most promising solid-state electrolyte system, and quinone redox systems remains elusive due to their inherent reactivity. Here, a library of quinone derivatives is selected as model electrode materials to ascertain the critical descriptors governing the (electro)chemical compatibility and subsequently the performances of Li6PS5Cl-based solid-state organic lithium metal batteries (LMBs). Compatibility is attained if the lowest unoccupied molecular orbital level of the quinone derivative is sufficiently higher than the highest occupied molecular orbital level of Li6PS5Cl. The energy difference is demonstrated to be critical in ensuring chemical compatibility during composite electrode preparation and enable high-efficiency operation of solid-state organic LMBs. Considering these findings, a general principle is proposed for the selection of quinone derivatives to be integrated with Li6PS5Cl, and two solid-state organic LMBs, based on 2,5-diamino-1,4-benzoquinone and 2,3,5,6-tetraamino-1,4-benzoquinone, are successfully developed and tested for the first time. Validating critical factors for the design of organic battery electrode materials is expected to pave the way for advancing the development of high-efficiency and long cycle life solid-state organic batteries based on sulfides electrolytes.

Improving the Efficiency and Stability of Perovskite Solar Cells by Refining the Perovskite-Electron Transport Layer Interface and Shielding the Absorber from UV Effects

This study aims to enhance the performance of perovskite solar cells (PSCs) by optimizing the interface between the perovskite and electron transport layers (ETLs). Additionally, we plan to protect the absorber layer from ultraviolet (UV) degradation using a ternary oxide system comprising SnO2, strontium stannate (SrSnO3), and strontium oxide (SrO). In this structure, the SnO2 layer functions as an electron transport layer, SrSnO3 acts as a layer for UV filtration, and SrO is employed to passivate the interface. SrSnO3 is characterized by its chemical stability, electrical conductivity, extensive wide band gap energy, and efficient absorption of UV radiation, all of which significantly enhance the photostability of PSCs against UV radiation. Furthermore, incorporating SrSnO3 into the ETL improves its electronic properties, potentially raising the energy level and improving alignment, thereby enhancing the electron transfer from the perovskite layer to the external circuit. Integrating SrO at the interface between the ETL and perovskite layer reduces interface defects, thereby reducing charge recombination and improving electron transfer. This improvement results in higher solar cell efficiency, reduced hysteresis, and extended device longevity. The benefits of this method are evident in the observed improvements: a noticeable increase in open-circuit voltage (Voc) from 1.12 to 1.16 V, an enhancement in the fill factor from 79.4 to 82.66%, a rise in the short-circuit current density (Jsc) from 24.5 to 24.9 mA/cm2 and notably, a marked improvement in the power conversion efficiency (PCE) of PSCs, from 21.79 to 24.06%. Notably, the treated PSCs showed only a slight decline in PCE, reducing from 24.15 to 22.50% over nearly 2000 h. In contrast, untreated SnO2 perovskite devices experienced a greater decline, with efficiency decreasing from 21.79 to 17.83% in just 580 h.

The past 10 years of molecular ferroelectrics: structures, design, and properties

Ferroelectricity, which has diverse important applications such as memory elements, capacitors, and sensors, was first discovered in a molecular compound, Rochelle salt, in 1920 by Valasek. Owing to their superiorities of lightweight, biocompatibility, structural tunability, mechanical flexibility, etc., the past decade has witnessed the renaissance of molecular ferroelectrics as promising complementary materials to commercial inorganic ferroelectrics. Thus, on the 100th anniversary of ferroelectricity, it is an opportune time to look into the future, specifically into how to push the boundaries of material design in molecular ferroelectric systems and finally overcome the hurdles to their commercialization. Herein, we present a comprehensive and accessible review of the appealing development of molecular ferroelectrics over the past 10 years, with an emphasis on their structural diversity, chemical design, exceptional properties, and potential applications. We believe that it will inspire intense, combined research efforts to enrich the family of high-performance molecular ferroelectrics and attract widespread interest from physicists and chemists to better understand the structure-function relationships governing improved applied functional device engineering.

Alleviating nanostructural phase impurities enhances the optoelectronic properties, device performance and stability of cesium-formamidinium metal-halide perovskites

The technique of alloying FA+ with Cs+ is often used to promote structural stabilization of the desirable α-FAPbI3 phase in halide perovskite devices. However, the precise mechanisms by which these alloying approaches improve the optoelectronic quality and enhance the stability have remained elusive. In this study, we advance that understanding by investigating the effect of cationic alloying in CsxFA1-xPbI3 perovskite thin-films and solar-cell devices. Selected-area electron diffraction patterns combined with microwave conductivity measurements reveal that fine Cs+ tuning (Cs0.15FA0.85PbI3) leads to a minimization of stacking faults and an increase in the photoconductivity of the perovskite films. Ultra-sensitive external quantum efficiency, kelvin-probe force microscopy and photoluminescence quantum yield measurements demonstrate similar Urbach energy values, comparable surface potential fluctuations and marginal impact on radiative emission yields, respectively, irrespective of Cs content. Despite this, these nanoscopic defects appear to have a detrimental impact on inter-grains'/domains' carrier transport, as evidenced by conductive-atomic force microscopy and corroborated by drastically reduced solar cell performance. Importantly, encapsulated Cs0.15FA0.85PbI3 devices show robust operational stability retaining 85% of the initial steady-state power conversion efficiency for 1400 hours under continuous 1 sun illumination at 35 °C, in open-circuit conditions. Our findings provide nuance to the famous defect tolerance of halide perovskites while providing solid evidence about the detrimental impact of these subtle structural imperfections on the long-term operational stability.

Integrating climate policies in the sustainability analysis of green chemicals

New and enhanced processes will not be the only drivers toward a sustainable chemical industry. Implementing climate policies will impact all components of the chemical supply chain over the following decades, making improvements in energy generation, material extraction, or transportation contribute to reducing the overall impacts of chemical technologies. Including this synergistic effect when comparing technologies offers a clearer vision of their future potential and may allow researchers to support their sustainability propositions more strongly. Ammonia and methanol production account for more than fifty percent of the CO2 emissions in this industry and are, therefore, excellent case studies. This work performs a prospective life cycle assessment until 2050 for fossil, blue, wind, and solar-based technologies under climate policies aiming to limit the global temperature rise to 1.5 °C, 2 °C, or 3.5 °C. The first finding is the inability of fossil-based routes to reduce their CO2 emissions beyond 10% by 2050 without tailored decarbonisation strategies, regardless of the chemical and climate policy considered. In contrast, green routes may produce chemicals with around 90% fewer emissions than today and even with net negative emissions (on a cradle-to-gate basis), as in the case of methanol (up to -1.4 kg CO2-eq per kg), mainly due to the contributions of technology development and increasing penetration of renewable energies. Overall, the combined production of these chemicals could be net-zero by 2050 despite their predicted two to fivefold increase in demand. Lastly, we propose a roadmap for progressive implementation by 2050 of green routes in 26 regions worldwide, applying the criterion of at least 80% reduction in climate change impacts when compared to their fossil alternatives. Furthermore, an exploratory prospective techno-economic assessment showed that by 2050, green routes could become more economically attractive. This work offers quantitative arguments to reinforce research, development, and policymaking efforts on green chemical routes reliant on renewable energies.

Pyroelectric-Accelerated Perovskite Photodetector for Picosecond Light Detection and Ranging

Light detection and ranging (LiDAR) is indispensable in applications such as unmanned aerial vehicles, autonomous driving, and biomimetic robots. However, the precision and available distance of LiDAR are constrained by the speed and sensitivity of the photodetector, necessitating the use of expensive and energy-consuming avalanche diodes. To address these challenges, in this study, a pyroelectricity-based acceleration strategy with 2D-(graded 3D) perovskite heterojunction is proposed to achieve a record high speed (27.7 ns with an active area of 9 mm2, and 176 ps with an active area of 0.2 mm2) and high responsivity (0.65 A W-1) at zero bias. This success is attributed to the unique mechanism where the electrons from the pyroelectric effect at the Cl-rich 2D/3D interface directly recombine with excess holes during light-dark transitions, breaking speed limitations related to carrier mobility and capacitive effect. Furthermore, the introduced pyroelectric effect significantly enhances the photoresponse, resulting in a self-powered external quantum efficiency exceeding 100%. The study also demonstrates precise position detection at the centimeter level. In conclusion, this research presents a pioneering approach for developing high-speed photodiodes with exceptional sensitivity, mitigating energy and cost concerns in LiDAR applications.

All-Inorganic Perovskite Solar Cells: Defect Regulation and Emerging Applications in Extreme Environments

All-inorganic perovskite solar cells (PSCs), such as CsPbX3, have garnered considerable attention recently, as they exhibit superior thermodynamic and optoelectronic stabilities compared to the organic-inorganic hybrid PSCs. However, the power conversion efficiency (PCE) of CsPbX3 PSCs is generally lower than that of organic-inorganic hybrid PSCs, as they contain higher defect densities at the interface and within the perovskite light-absorbing layers, resulting in higher non-radiative recombination and voltage loss. Consequently, defect regulation has been adopted as an important strategy to improve device performance and stability. This review aims to comprehensively summarize recent progresses on the defect regulation in CsPbX3 PSCs, as well as their cutting-edge applications in extreme scenarios. The underlying fundamental mechanisms leading to the defect formation in the crystal structure of CsPbX3 PSCs are firstly discussed, and an overview of literature-adopted defect regulation strategies in the context of interface, internal, and surface engineering is provided. Cutting-edge applications of CsPbX3 PSCs in extreme environments such as outer space and underwater situations are highlighted. Finally, a summary and outlook are presented on future directions for achieving higher efficiencies and superior stability in CsPbX3 PSCs.

Liquid-Liquid Phase Separation-Mediated Photocatalytic Subcellular Hybrid System for Highly Efficient Hydrogen Production

Plant chloroplasts have a highly compartmentalized interior, essential for executing photocatalytic functions. However, the construction of a photocatalytic reaction compartment similar to chloroplasts in inorganic-biological hybrid systems (IBS) has not been reported. Drawing inspiration from the compartmentalized chloroplast and the phenomenon of liquid-liquid phase separation, herein, a new strategy is first developed for constructing a photocatalytic subcellular hybrid system through liquid-liquid phase separation technology in living cells. Photosensitizers and in vivo expressed hydrogenases are designed to coassemble within the cell to create subcellular compartments for synergetic photocatalysis. This compartmentalization facilitates efficient electron transfer and light energy utilization, resulting in highly effective H2 production. The subcellular compartments hybrid system (HM/IBSCS) exhibits a nearly 87-fold increase in H2 production compared to the bare bacteria/hybrid system. Furthermore, the intracellular compartments of the photocatalytic reactor enhance the system's stability obviously, with the bacteria maintaining approximately 81% of their H2 production activity even after undergoing five cycles of photocatalytic hydrogen production. The research brings forward visionary prospects for the field of semi-artificial photosynthesis, offering new possibilities for advancements in areas such as renewable energy, biomanufacturing, and genetic engineering.

Ordered Perovskite Structure with Functional Units for High Performance and Stable Solar Cells

Ion migration is one of the most critical challenges that affects the stability of metal-halide perovskite solar cells (PSCs). However, the current arsenal of available strategies for solving this issue is limited. Here, novel perovskite active layers following the concept of ordered structures with functional units (OSFU) to intrinsically suppress ion migration, in which a three-dimensional (3D) perovskite layer is deposited by vapor deposition for light absorption and a 2D layer is deposited by solution process for ion inhibition, are constructed. As a promising result, the activation energy of ion migration increases from 0.36 eV for the conventional perovskite to 0.54 eV for the OSFU perovskite. These devices exhibit substantially enhanced operational stability in comparison with the conventional ones, retaining >85% of their initial efficiencies after 1200 h under ISOS-L-1. Moreover, the OSFU devices show negligible fatigue behavior with a robust performance under light/dark cycling aging test (ISOS-LC-1 protocol), which demonstrates the promising application of functional motif theory in this field.

Elucidating the development of cooperative anode-biofilm-structures

Microbial electrochemical systems are a highly versatile platform technology with a particular focus on the interplay of chemical and electrical energy conversion and offer immense potential for a sustainable bioeconomy. The industrial realization of this potential requires a critical focus on biofilm optimization if performance is to be controlled over a long period of time. Moreover, the aspect and influence of cooperativity has to be addressed as many applied anodic bioelectrochemical systems will most likely be operated with a diversity of interacting microbial species. Hence, the aim of this study was to analyze how interspecies dependence and cooperativity of a model community influence the development of anodic biofilms. To investigate biofilm activity in a spatially resolved manner, a microfluidic bioelectrochemical flow cell was developed that can be equipped with user-defined electrode materials and operates under laminar flow conditions. With this infrastructure, the development of single and co-culture biofilms of the two model organisms Shewanella oneidensis and Geobacter sulfurreducens on graphite electrodes was monitored by optical coherence tomography analysis. The interdependence in the co-culture biofilm was achieved by feeding the community with lactate, which is converted by S. oneidensis into acetate, which in turn serves as substrate for G. sulfurreducens. The results show that co-cultivation resulted in the formation of denser biofilms than in single culture. Moreover, we hypothesize that S. oneidensis in return utilizes the conductive biofilm matrix build by G. sulfurreducens for direct interspecies electron transfer (DIET) to the anode. FISH analysis revealed that the biofilms consisted of approximately two-thirds G. sulfurreducens cells, which most likely formed a conductive 3D network throughout the biofilm matrix, in which evenly distributed tubular S. oneidensis colonies were embedded without direct contact to the anode surface. Live/dead staining shows that the outermost biofilm contained almost exclusively dead cells (98 %), layers near the anode contained 45-56 % and the entire biofilm contained 82 % live cells. Our results exemplify how the architecture of the exoelectrogenic biofilm dynamically adapts to the respective process conditions.

High Open-Circuit Voltage Organic Solar Cells with 19.2% Efficiency Enabled by Synergistic Side-Chain Engineering

Restricted by the energy-gap law, state-of-the-art organic solar cells (OSCs) exhibit relatively low open-circuit voltage (VOC) because of large nonradiative energy losses (ΔEnonrad). Moreover, the trade-off between VOC and external quantum efficiency (EQE) of OSCs is more distinctive; the power conversion efficiencies (PCEs) of OSCs are still <15% with VOCs of >1.0 V. Herein, the electronic properties and aggregation behaviors of non-fullerene acceptors (NFAs) are carefully considered and then a new NFA (Z19) is delicately designed by simultaneously introducing alkoxy and phenyl-substituted alkyl chains to the conjugated backbone. Z19 exhibits a hypochromatic-shifted absorption spectrum, high-lying lowest unoccupied molecular orbital energy level and ordered 2D packing mode. The D18:Z19-based blend film exhibits favorable phase separation with face-on dominated molecular orientation, facilitating charge transport properties. Consequently, D18:Z19 binary devices afford an exciting PCE of 19.2% with a high VOC of 1.002 V, surpassing Y6-2O-based devices. The former is the highest PCE reported to date for OSCs with VOCs of >1.0 V. Moreover, the ΔEnonrad of Z19- (0.200 eV) and Y6-2O-based (0.155 eV) devices are lower than that of Y6-based (0.239 eV) devices. Indications are that the design of such NFA, considering the energy-gap law, could promote a new breakthrough in OSCs.

Graphene-Perovskite Fibre Photodetectors

The integration of optoelectronic devices, such as transistors and photodetectors (PDs), into wearables and textiles is of great interest for applications such as healthcare and physiological monitoring. These require flexible/wearable systems adaptable to body motions, thus materials conformable to non-planar surfaces, and able to maintain performance under mechanical distortions. Here, fibre PDs are prepared by combining rolled graphene layers and photoactive perovskites. Conductive fibres (~500 Ωcm-1) are made by rolling single-layer graphene (SLG) around silica fibres, followed by deposition of a dielectric layer (Al2O3 and parylene C), another rolled SLG as a channel, and perovskite as photoactive component. The resulting gate-tunable PD has a response time~9ms, with an external responsivity~22kAW-1 at 488nm for a 1V bias. The external responsivity is two orders of magnitude higher, and the response time one order of magnitude faster, than state-of-the-art wearable fibre-based PDs. Under bending at 4mm radius, up to~80% photocurrent is maintained. Washability tests show~72% of initial photocurrent after 30 cycles, promising for wearable applications.

High-capacity dilithium hydroquinone cathode material for lithium-ion batteries

Lithiated organic cathode materials show great promise for practical applications in lithium-ion batteries owing to their Li-reservoir characteristics. However, the reported lithiated organic cathode materials still suffer from strict synthesis conditions and low capacity. Here we report a thermal intermolecular rearrangement method without organic solvents to prepare dilithium hydroquinone (Li2Q), which delivers a high capacity of 323 mAh g-1 with an average discharge voltage of 2.8 V. The reversible conversion between orthorhombic Li2Q and monoclinic benzoquinone during charge/discharge processes is revealed by in situ X-ray diffraction. Theoretical calculations show that the unique Li-O channels in Li2Q are beneficial for Li+ ion diffusion. In situ ultraviolet-visible spectra demonstrate that the dissolution issue of Li2Q electrodes during charge/discharge processes can be handled by separator modification, resulting in enhanced cycling stability. This work sheds light on the synthesis and battery application of high-capacity lithiated organic cathode materials.

Cost-competitive decentralized ammonia fertilizer production can increase food security

The current centralized configuration of the ammonia industry makes the production of nitrogen fertilizers susceptible to the volatility of fossil fuel prices and involves complex supply chains with long-distance transport costs. An alternative consists of on-site decentralized ammonia production using small modular technologies, such as electric Haber-Bosch or electrocatalytic reduction. Here we evaluate the cost-competitiveness of producing low-carbon ammonia at the farm scale, from a solar agrivoltaic system, or using electricity from the grid, within a novel global fertilizer industry. Projected costs for decentralized ammonia production are compared with historical market prices from centralized production. We find that the cost-competitiveness of decentralized production relies on transport costs and supply chain disruptions. Taking both factors into account, decentralized production could achieve cost-competitiveness for up to 96% of the global ammonia demand by 2030. These results show the potential of decentralized ammonia technologies in revolutionizing the fertilizer industry, particularly in regions facing food insecurity.

Novel Heterostructure-Based CoFe and Cobalt Oxysulfide Nanocubes for Effective Bifunctional Electrocatalytic Water and Urea Oxidation

The development of effective oxygen evolution reaction (OER) and urea oxidation reaction (UOR) on heterostructure electrocatalysts with specific interfaces and characteristics provides a distinctive character. In this study, heterostructure nanocubes (NCs) comprising inner cobalt oxysulfide (CoOS) NCs and outer CoFe (CF) layered double hydroxide (LDH) are developed using a hydrothermal methodology. During the sulfidation process, the divalent sulfur ions (S2-) are released from the breakdown of the sulfur source and react with the Co-precursors on the surface leading to the transformation of CoOH nanorods into CoOS nanocubes. Further, X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) analyses reveal that the interactions at the interface of the CF@CoOS NCs significantly altered the electronic structure, thus enhancing the electrocatalytic performance. The optimal catalysts exhibited effective OER and UOR activities, the attained potentials are 1.51 and 1.36 V. This remarkable performance is attributable to the induction of electron transfer from the CoFe LDH to CoOS, which reduces the energy barrier of the intermediates for the OER and UOR. Furthermore, an alkaline water and urea two-cell electrolyzer assembled using CF@CoOS-2 NCs and Pt/C as the anode and cathode requires a cell voltage of 1.63 and 1.56 V along with a durability performance.

Gas Evolution Kinetics in Overlithiated Positive Electrodes and its Impact on Electrode Design

Increasing lithium contents within the lattice of positive electrode materials is projected in pursuit of high-energy-density batteries. However, it intensifies the release of lattice oxygen and subsequent gas evolution during operations. This poses significant challenges for managing internal pressure of batteries, particularly in terms of the management of gas evolution in composite electrodes-an area that remains largely unexplored. Conventional assumptions postulate that the total gas evolution is estimated by multiplying the total particle count by the quantities of gas products from an individual particle. Contrarily, this investigation on overlithiated materials-a system known to release the lattice oxygen-demonstrates that loading densities and inter-particle spacing in electrodes significantly govern gas evolution rates, leading to distinct extents of gas formation despite of an equivalent quantity of released lattice oxygen. Remarkably, this study discoveres that O2 and CO2 evolution rates are proportional to 1O2 concentration by the factor of second and first-order, respectively. This indicates an exceptionally greater change in the evolution rate of O2 compared to CO2 depending on local 1O2 concentration. These insights pave new routes for more sophisticated approaches to manage gas evolution within high-energy-density batteries.

Significance of a minor pilin PilV in biofilm cohesion of Geobacter sulfurreducens

Bacterial adhesion plays a vital role in forming and shaping the structure of electroactive biofilms that are essential for the performance of bioelectrochemical systems (BESs). Type IV pili are known to mediate cell adhesion in many Gram-negative bacteria, but the mechanism of pili-mediated cell adhesion of Geobacter species on anode surface remains unclear. Herein, a minor pilin PilV2 was found to be essential for cell adhesion ability of Geobacter sulfurreducens since the lack of pilV2 gene depressed the cell adhesion capability by 81.2% in microplate and the anodic biofilm density by 23.1 % at -0.1 V and 37.7 % at -0.3 V in BESs. The less cohesiveness of mutant biofilms increased the charge transfer resistance and biofilm resistance, which correspondingly lowered current generation of the pilV2-deficient strain by up to 63.2 % compared with that of the wild-type strain in BESs. The deletion of pilV2 posed an insignificant effect on the production of extracellular polysaccharides, pili, extracellular cytochromes and electron shuttles that are involved in biofilm formation or extracellular electron transfer (EET) process. This study demonstrated the significance of pilV2 gene in cell adhesion and biofilm formation of G. sulfurreducens, as well as the importance of pili-mediated adhesion for EET of electroactive biofilm.

Catalytically Active Carbon for Oxygen Reduction Reaction in Energy Conversion: Recent Advances and Future Perspectives

The shortage and unevenness of fossil energy sources are affecting the development and progress of human civilization. The technology of efficiently converting material resources into energy for utilization and storage is attracting the attention of researchers. Environmentally friendly biomass materials are a treasure to drive the development of new-generation energy sources. Electrochemical theory is used to efficiently convert the chemical energy of chemical substances into electrical energy. In recent years, significant progress has been made in the development of green and economical electrocatalysts for oxygen reduction reaction (ORR). Although many reviews have been reported around the application of biomass-derived catalytically active carbon (CAC) catalysts in ORR, these reviews have only selected a single/partial topic (including synthesis and preparation of catalysts from different sources, structural optimization, or performance enhancement methods based on CAC catalysts, and application of biomass-derived CACs) for discussion. There is no review that systematically addresses the latest progress in the synthesis, performance enhancement, and applications related to biomass-derived CAC-based oxygen reduction electrocatalysts synchronously. This review fills the gap by providing a timely and comprehensive review and summary from the following sections: the exposition of the basic catalytic principles of ORR, the summary of the chemical composition and structural properties of various types of biomass, the analysis of traditional and the latest popular biomass-derived CAC synthesis methods and optimization strategies, and the summary of the practical applications of biomass-derived CAC-based oxidative reduction electrocatalysts. This review provides a comprehensive summary of the latest advances to provide research directions and design ideas for the development of catalyst synthesis/optimization and contributes to the industrialization of biomass-derived CAC electrocatalysis and electric energy storage.

Toward the High-Voltage Stability of Layered Oxide Cathodes for Sodium-Ion Batteries: Challenges, Progress, and Perspectives

Sodium-ion batteries (SIBs) have garnered significant attention as ideal candidates for large-scale energy storage due to their notable advantages in terms of resource availability and cost-effectiveness. However, there remains a substantial energy density gap between SIBs and commercially available lithium-ion batteries (LIBs), posing challenges to meeting the requirements of practical applications. The fabrication of high-energy cathodes has emerged as an efficient approach to enhancing the energy density of SIBs, which commonly requires cathodes operating in high-voltage regions. Layered oxide cathodes (LOCs), with low cost, facile synthesis, and high theoretical specific capacity, have emerged as one of the most promising candidates for commercial applications. However, LOCs encounter significant challenges when operated in high-voltage regions such as irreversible phase transitions, migration and dissolution of metal cations, loss of reactive oxygen, and the occurrence of serious interfacial parasitic reactions. These issues ultimately result in severe degradation in battery performance. This review aims to shed light on the key challenges and failure mechanisms encountered by LOCs when operated in high-voltage regions. Additionally, the corresponding strategies for improving the high-voltage stability of LOCs are comprehensively summarized. By providing fundamental insights and valuable perspectives, this review aims to contribute to the advancement of high-energy SIBs.

Defect Engineering and Emission Tuning of Wide-Bandgap MAPbCl3 Perovskite

Lead-chloride perovskites are promising candidates for optoelectronic applications, such as visible-blind UV photodetection. It remains unclear how the deep defects in this wide-bandgap material impact the carrier recombination dynamics. In this work, we study the defect properties of MAPbCl3 (MA = CH3NH3) based on photoluminescence (PL) measurements. Our investigations show that apart from the intrinsic emission, four sub-bandgap emissions emerge, which are very likely to originate from the radiative recombination of excitons bound to several intrinsic vacancy and interstitial defects. The intensity of various emission features can be tuned by adjusting the type and ratio of precursors used during synthesis. Our study not only provides important insights into the defect property and carrier recombination mechanism in this class of material but also demonstrates efficient strategies for defect passivation and engineering, paving the way for further development of lead-chloride perovskite-based optoelectronic devices.

Extraordinary Structural Reconstruction of Nanolaminated Ta2FeC MAX Phase for Enhanced Oxygen Evolution Performance

Renewable energy technologies, such as water splitting, heavily depend on the oxygen evolution reaction (OER). Nanolaminated ternary compounds, referred to as MAX phases, show great promise for creating efficient electrocatalysts for OER. However, their limited intrinsic oxidative resistance hinders the utilization of conductivity in Mn+1Xn layers, leading to reduced activity. In this study, a method is proposed to improve the poor inoxidizability of MAX phases by carefully adjusting the elemental composition between Mn+1Xn layers and single-atom-thick A layers. The resulting Ta2FeC catalyst demonstrates superior performance compared to conventional Fe/C-based catalysts with a remarkable record-low overpotential of 247 mV (@10 mA cm-2) and sustained activity for over 240 h. Notably, during OER processing, the single-atom-thick Fe layer undergoes self-reconstruction and enrichment from the interior of the Ta2FeC MAX phase toward its surface, forming a Ta2FeC@Ta2C@FeOOH heterostructure. Through density functional theory (DFT) calculations, this study has found that the incorporation of Ta2FeC@Ta2C not only enhances the conductivity of FeOOH but also reduces the covalency of Fe─O bonds, thus alleviating the oxidation of Fe3+ and O2-. This implies that the Ta2FeC@Ta2C@FeOOH heterostructure experiences less lattice oxygen loss during the OER process compared to pure FeOOH, leading to significantly improved stability. These results highlight promising avenues for further exploration of MAX phases by strategically engineering M- and A-site engineering through multi-metal substitution, to develop M2AX@M2X@AOOH-based catalysts for oxygen evolution.

Low-temperature strain-free encapsulation for perovskite solar cells and modules passing multifaceted accelerated ageing tests

Perovskite solar cells promise to be part of the future portfolio of photovoltaic technologies, but their instability is slow down their commercialization. Major stability assessments have been recently achieved but reliable accelerated ageing tests on beyond small-area cells are still poor. Here, we report an industrial encapsulation process based on the lamination of highly viscoelastic semi-solid/highly viscous liquid adhesive atop the perovskite solar cells and modules. Our encapsulant reduces the thermomechanical stresses at the encapsulant/rear electrode interface. The addition of thermally conductive two-dimensional hexagonal boron nitride into the polymeric matrix improves the barrier and thermal management properties of the encapsulant. Without any edge sealant, encapsulated devices withstood multifaceted accelerated ageing tests, retaining >80% of their initial efficiency. Our encapsulation is applicable to the most established cell configurations (direct/inverted, mesoscopic/planar), even with temperature-sensitive materials, and extended to semi-transparent cells for building-integrated photovoltaics and Internet of Things systems.

Conjugated Polymer/Recombinant Escherichia coli Biohybrid Systems for Photobiocatalytic Hydrogen Production

Biohybrid photocatalysts are composite materials that combine the efficient light-absorbing properties of synthetic materials with the highly evolved metabolic pathways and self-repair mechanisms of biological systems. Here, we show the potential of conjugated polymers as photosensitizers in biohybrid systems by combining a series of polymer nanoparticles with engineered Escherichia coli cells. Under simulated solar light irradiation, the biohybrid system consisting of fluorene/dibenzo [b,d]thiophene sulfone copolymer (LP41) and recombinant E. coli (i.e., a LP41/HydA BL21 biohybrid) shows a sacrificial hydrogen evolution rate of 3.442 mmol g-1 h-1 (normalized to polymer amount). It is over 30 times higher than the polymer photocatalyst alone (0.105 mmol g-1 h-1), while no detectable hydrogen was generated from the E. coli cells alone, demonstrating the strong synergy between the polymer nanoparticles and bacterial cells. The differences in the physical interactions between synthetic materials and microorganisms, as well as redox energy level alignment, elucidate the trends in photochemical activity. Our results suggest that organic semiconductors may offer advantages, such as solution processability, low toxicity, and more tunable surface interactions with the biological components over inorganic materials.

Buried Interface Passivation Using Organic Ammonium Salts for Efficient Inverted CsMAFA Perovskite Solar Cell Performance

This study uses different doping ratios of CsCl and MACl dual additives to improve the quality of the perovskite, where CsCl reduces the perovskite trap density and increases the resistance of charge recombination, and MACl was used to improve the phase stability. Finally, the composition of Cs0.1MA0.09FA0.81PbCl0.14I2.86 perovskite solar cell (PeSC) can achieve better open-circuit voltage (Voc), short-circuit current density (Jsc), and photoelectric conversion efficiency (PCE). To achieve a better PCE of PeSC, the use of organic ammonium salt butane-1,4-diammonium iodide (BDAI2) to passivate the perovskite bottom surface (buried interface) can effectively suppress the formation of defects at the perovskite buried interface, obtain higher crystallinity, and thereby reduce the probability of carrier recombination. The Jsc, fill factor (FF), and PCE of the PeSC based on BDAI2 passivation increased from 24.0 mA cm-2, 74.1%, and 18.6% to 24.5 mA cm-2, 79.9%, and 20.5%, respectively.

Complementary Weaknesses: A Win-Win Approach for rGO/CdS to Improve the Energy Conversion Performance of Integrated Photorechargeable Li-S Batteries

Integrating solar energy into rechargeable battery systems represents a significant advancement towards sustainable energy storage solutions. Herein, we propose a win-win solution to reduce the shuttle effect of polysulfide and improve the photocorrosion stability of CdS, thereby enhancing the energy conversion efficiency of rGO/CdS-based photorechargeable integrated lithium-sulfur batteries (PRLSBs). Experimental results show that CdS can effectively anchor polysulfide under sunlight irradiation for 20 minutes. Under a high current density (1 C), the discharge-specific capacity of the PRLSBs increased to 971.30 mAh g-1, which is 113.3 % enhancement compared to that of under dark condition (857.49 mAh g-1). Remarkably, without an electrical power supply, the PRLSBs can maintain a 21 hours discharge process following merely 1.5 hours of light irradiation, achieving a breakthrough solar-to-electrical energy conversion efficiency of up to 5.04 %. Ex situ X-ray photoelectron spectroscopy (XPS) and in situ Raman analysis corroborate the effectiveness of this complementary weakness approach in bolstering redox kinetics and curtailing polysulfide dissolution in PRLSBs. This work showcases a feasible strategy to develop PRLSBs with potential dual-functional metal sulfide photoelectrodes, which will be of great interest in future-oriented off-grid photocell systems.

The Renaissance of Poly(3-hexylthiophene) as a Promising Hole-Transporting Material Toward Efficient and Stable Perovskite Solar Cells

To push the commercialization of the promising photovoltaic technique of perovskite solar cells (PSCs), the three-element golden law of efficiency, stability, and cost should be followed. As the key component of PSCs, hole-transporting materials (HTMs) involving widely-used organic semiconductors such as 2,2',7,7'-tetrakis-(N,N-di-4-methoxyphenylamino)-9,9'-spirobifluorene (Spiro-OMeTAD) or poly(triarylamine) (PTAA) usually suffer high-cost preparation and low operational stability. Fortunately, the studies on the classical p-type polymer poly(3-hexylthiophene) (P3HT) as an alternative HTM have recently sparked a broad interest due to its low-cost synthesis, excellent batch-to-batch purity, superior hole conductivity as well as controllable and stable film morphology. Despite this, the device efficiency still lags behind P3HT-based PSCs mainly owing to the mismatched energy level and poor interfacial contact between P3HT and the perovskite layer. Hence, in this review, the study timely summarizes the developed strategies for overcoming the corresponding issues such as interface engineering, morphology regulation, and formation of composite HTMs from which some critical clues can be extracted to provide guidance for further boosting the efficiency and stability of P3HT-based devices. Finally, in the outlook, the future research directions either from the viewpoint of material design or device engineering are outlined.

A Simple Organo-Electrocatalysis System for the Chlor-Related Industry

Consuming a substantial quantum of energy (~165 TW h), the chlor-alkali industry garners considerable scholarly and industrial interest, with the anode reaction involving the oxidation of chloride ions being a paramount determinant of reaction rates. While the dimensionally stable anode (DSA) displays commendable catalytic activity and longevity, they rely on precious metals and exhibit a non-negligible side reaction in sodium hypochlorite (NaClO) production, underscoring the appeal of metal-free alternatives. However, the molecules and systems currently available are characterized by intricate complexity and are not amenable to large-scale production. Herein, we have successfully developed an economical and highly efficient molecular catalyst, demonstrating superior performance compared with the former organic molecules in the chloride ion oxidation process (COP) for the production of both chlorine gas (Cl2) and NaClO. The molecule of 2N only needs 92 mV to reach a current density of 1000 mA cm-2, with a small cost of only 0.002 $ g-1. Furthermore, we propose a novel mechanism underpinned by non-covalent interactions, serving as the foundation for an innovative approach to the design of efficient anodes for the COP.

In Situ Construction of a Multifunctional Interphase Enabling Continuous Capture of Unstable Lattice Oxygen Under Ultrahigh Voltages

The use of nickel-rich layered materials as cathodes can boost the energy density of lithium batteries. However, developing a safe and long-term stable nickel-rich layered cathode is challenging primarily due to the release of lattice oxygen from the cathode during cycling, especially at high voltages, which will cause a series of adverse effects, leading to battery failure and thermal runaway. Surface coating is often considered effective in capturing active oxygen species; however, its process is rather complicated, and it is difficult to maintain intact on the cathode with large volume changes during cycling. Here, we propose an in situ construction of a multifunctional cathode/electrolyte interphase (CEI), which is easy to prepare, repairable, and, most importantly, capable of continuously capturing active oxygen species during the entire life span. This unique protective mechanism notably improves the cycling stability of Li||LiNi0.8Co0.1Mn0.1O2 (NCM811) cells at rigorous working conditions, including ultrahigh voltage (4.8 V), high temperature (60 °C), and fast charging (10 C). An industrial 1 A h graphite||NCM811 pouch cell achieved stable operation of 600 cycles with a capacity retention of 79.6% at 4.4 V, exhibiting great potential for practical use. This work provides insightful guidance for constructing a multifunctional CEI to bypass limitations associated with high-voltage operations of nickel-rich layered cathodes.

Solvent-free preparation and thermocompression self-assembly: an exploration of performance improvement strategies for perovskite solar cells

Perovskite solar cells (PSCs) exhibit sufficient technological efficiency and economic competitiveness. However, their poor stability and scalability are crucial factors limiting their rapid development. Therefore, achieving both high efficiency and good stability is an urgent challenge. In addition, the preparation methods for PSCs are currently limited to laboratory-scale methods, so their commercialization requires further research. Effective packaging technology is essential to protect the PSCs from degradation by external environmental factors and ensure their long-term stability. The industrialization of PSCs is also inseparable from the preparation technology of perovskite thin films. This review discusses the solvent-free preparation of PSCs, shedding light on the factors that affect PSC performance and strategies for performance enhancement. Furthermore, this review analyzes the existing simulation techniques that have contributed to a better understanding of the interfacial evolution of PSCs during the packaging process. Finally, the current challenges and possible solutions are highlighted, providing insights to facilitate the development of highly efficient and stable PSC modules to promote their widespread application.

Destabilization of Oxidized Lattice Oxygen in Layered Oxide Cathode

Integrating anion-redox capacity with orthodox cation-redox capacity is deemed as a promising solution for high-energy-density battery cathodes surmounting the present technical bottlenecks. However, the evolution of oxidized oxygen species during the electrochemical or chemical process easily jeopardizes the reversibility of oxygen redox and remains poorly understood. Herein, we showcase the gradual conversion of the π-interacting oxygen (localized hole states on O) to the σ-interacting oxygen upon resting at a high voltage for P3-type Na0.6Li0.2Mn0.8O2 with nominally stable ribbon-like superstructure, accompanied by the O-O dimerization and the local structural reorganization. We further pinpoint an abnormal Li+ migration process from the alkali-metal layer to the transition-metal layer for desodiated P3-Na0.6Li0.2Mn0.8O2, thereby leading to a partial reconstruction of the ribbon superstructure. The high-voltage plateau of oxygen-redox cathodes is concluded to be exclusively controlled by the oxygen stabilization mechanism rather than the superstructure ordering. In addition, there exists a kinetic competition between π and σ interaction during the uninterrupted electrochemical process.

Agriculture and environmental management through nanotechnology: Eco-friendly nanomaterial synthesis for soil-plant systems, food safety, and sustainability

Through the advancement of nanotechnology, agricultural and food systems are undergoing strategic enhancements, offering innovative solutions to complex problems. This scholarly essay thoroughly examines nanotechnological innovations and their implications within these critical industries. Traditional practices are undergoing radical transformation as nanomaterials emerge as novel agents in roles traditionally filled by fertilizers, pesticides, and biosensors. Micronutrient management and preservation techniques are further enhanced, indicating a shift towards more nutrient-dense and longevity-oriented food production. Nanoparticles (NPs), with their unique physicochemical properties, such as an extraordinary surface-to-volume ratio, find applications in healthcare, diagnostics, agriculture, and other fields. However, concerns about their potential overuse and bioaccumulation raise unanswered questions about their health effects. Molecule-to-molecule interactions and physicochemical dynamics create pathways through which nanoparticles cause toxicity. The combination of nanotechnology and environmental sustainability principles leads to the examination of green nanoparticle synthesis. The discourse extends to how nanomaterials penetrate biological systems, their applications, toxicological effects, and dissemination routes. Additionally, this examination delves into the ecological consequences of nanomaterial contamination in natural ecosystems. Employing robust risk assessment methodologies, including the risk allocation framework, is recommended to address potential dangers associated with nanotechnology integration. Establishing standardized, universally accepted guidelines for evaluating nanomaterial toxicity and protocols for nano-waste disposal is urged to ensure responsible stewardship of this transformative technology. In conclusion, the article summarizes global trends, persistent challenges, and emerging regulatory strategies shaping nanotechnology in agriculture and food science. Sustained, in-depth research is crucial to fully benefit from nanotechnology prospects for sustainable agriculture and food systems.

High-entropy alloy screening for halide perovskites

As the concept of high-entropy alloying (HEA) extends beyond metals, new materials screening methods are needed. Halide perovskites (HP) are a prime case study because greater stability is needed for photovoltaics applications, and there are 322 experimentally observed HP end-members, which leads to more than 1057 potential alloys. We screen HEAHP by first calculating the configurational entropy of 106 equimolar alloys with experimentally observed end-members. To estimate enthalpy at low computational cost, we turn to the delta-lattice parameter approach, a well-known method for predicting III-V alloy miscibility. To generalize the approach for non-cubic crystals, we introduce the parameter of unit cell volume coefficient of variation (UCV), which does a good job of predicting the experimental HP miscibility data. We use plots of entropy stabilization versus UCV to screen promising alloys and identify 102 HEAHP of interest.

Band gap tuning of perovskite solar cells for enhancing the efficiency and stability: issues and prospects

The intriguing optoelectronic properties, diverse applications, and facile fabrication techniques of perovskite materials have garnered substantial research interest worldwide. Their outstanding performance in solar cell applications and excellent efficiency at the lab scale have already been proven. However, owing to their low stability, the widespread manufacturing of perovskite solar cells (PSCs) for commercialization is still far off. Several instability factors of PSCs, including the intrinsic and extrinsic instability of perovskite materials, have already been identified, and a variety of approaches have been adopted to improve the material quality, stability, and efficiency of PSCs. In this review, we have comprehensively presented the significance of band gap tuning in achieving both high-performance and high-stability PSCs in the presence of various degradation factors. By investigating the mechanisms of band gap engineering, we have highlighted its pivotal role in optimizing PSCs for improved efficiency and resilience.