Singlet Oxygen-Engaged Selective Photo-Oxidation over Pt Nanocrystals/Porphyrinic MOF: The Roles of Photothermal Effect and Pt Electronic State

Visible light mediated photocatalysis by lanthanide metal-organic frameworks: enhanced specificity and mechanistic insights

The utilization of earth-abundant photosensitizers with visible light absorption to enable sustainable photocatalysis is a long-standing challenge. Overcoming such a challenge, in this work, two lanthanide (Ln3+ = Tb, Eu) based metal-organic frameworks (Ln-MOFs) have been synthesized utilizing a Co3+-based metalloligand. Both Ln-MOFs function as remarkable photocatalysts for the selective oxidation of assorted alcohols and sulfides to their corresponding aldehydes/ketones and sulfoxides using visible light. The photophysical behavior of both Ln-MOFs and mechanism of photocatalysis is comprehensively investigated using time-resolved transient absorption spectroscopy, electrochemical impedance spectroscopy, electron paramagnetic resonance spectroscopy, photoluminescence and phosphorescence studies. In both Ln-MOFs, a metalloligand acts as a light-harvester, being excited by visible light, while Ln3+ ions endow the resulting MOFs with long-lived triplet excited states. Ultrafast transient absorption spectroscopy, further supported by electron paramagnetic resonance spectra, revealed excited-state electron transfer from metalloligands to the Ln3+ ions and transient generation of Ln2+ sites alongside the facilitation of intersystem crossing. The excited Ln2+ ions transfer energy to the ground-state triplet oxygen (3O2) to generate singlet oxygen (1O2). The HOMO-LUMO positions of both Ln-MOFs support the generation of ˙O2 - and 1O2 but inhibit strongly-oxidizing yet non-selective ˙OH radicals. Scavenger experiments, 1O2 traps and electron paramagnetic resonance spectra confirmed the generation of singlet oxygen. The heavy-metal effect of a lanthanide ion in Ln-MOFs for the generation of triplet excitons is confirmed by the synthesis of a non-heavy-metal analogue involving a zinc ion via a single-crystal-to-single-crystal transformation strategy. The present results are noteworthy and may aid in the development of other earth-abundant metalloligand-based photocatalysts for challenging yet sustainable catalysis.

Energy transfer-mediated multiphoton synergistic excitation for selective C(sp3)-H functionalization with coordination polymer

Activation and selective oxidation of inert C(sp3)-H bonds remain one of the most challenging tasks in current synthetic chemistry due to the inherent inertness of C(sp3)-H bonds. In this study, inspired by natural monooxygenases, we developed a coordination polymer with naphthalenediimide (NDI)-based ligands and binuclear iron nodes. The mixed-valence FeIIIFeII species and chlorine radicals (Cl•) are generated via ligand-to-metal charge transfer (LMCT) between FeIII and chlorine ions. These Cl• radicals abstract a hydrogen atom from the inert C(sp3)-H bond of alkanes via hydrogen atom transfer (HAT). In addition, NDI converts oxygen to 1O2 via energy transfer (EnT), which then coordinates to FeII, forming an FeIV = O intermediate for the selective oxidation of C(sp3)-H bonds. This synthetic platform, which combines photoinduced EnT, LMCT and HAT, provides a EnT-mediated parallel multiphoton excitation strategy with kinetic synergy effect for selective C(sp3)-H oxidation under mild conditions and a blueprint for designing coordination polymer-based photocatalysts for C(sp3)-H bond oxidation.

Selective Generation of Reactive Oxygen Species in Photocatalytic Oxidation by Tuning Porphyrin-Based COFs' Dimensionality

Regulating the selective generation of reactive oxygen species (ROS) is a significant challenge in the field of photocatalytic oxidation, with successful approaches still being limited. Herein, we present a strategy to selectively generate singlet oxygen (1O2) and superoxide radicals (O2•-) by tuning the dimensionality of porphyrin-based covalent organic frameworks (COFs). The transformation of COFs from three-dimensional (3D) solids to two-dimensional (2D) sheets was achieved through the reversible protonation of the imine bond. Upon irradiation, both bulk and thin-layer COF-367 can transfer energy to O2 to generate 1O2. However, thin-layer COF-367 exhibited a superior performance compared to its bulk counterpart in activating O2 to form the O2•- radicals via electron transfer. After excluding the influences of the band structure, O2 adsorption energy, and frontier orbital composition attributed to the dimensionality of the COFs, it is reasonably speculated that the variance in ROS generation arises from the differential exposure ratios of the active surfaces, leading to distinct reaction pathways between the carrier and O2. This study is the first to explore the modulation mechanism of COF dimensionality on the activation of the O2 pathway, underscoring the importance of considering COF dimensionality in photocatalytic reactions.

Revolutionizing Tetracycline Hydrochloride Remediation: 3D Motile Light-Driven MOFs Based Micromotors in Harsh Saline Environments

Traditional light-driven metal-organic-frameworks (MOFs)-based micromotors (MOFtors) are typically constrained to two-dimensional (2D) motion under ultraviolet or near-infrared light and often demonstrate instability and susceptibility to ions in high-saline environments. This limitation is particularly relevant to employing micromotors in water purification, as real wastewater is frequently coupled with high salinity. In response to these challenges, ultrastable MOFtors capable of three-dimensional (3D) motion under a broad spectrum of light through thermophoresis and electrophoresis are successfully synthesized. The MOFtors integrated photocatalytic porphyrin MOFs (PCN-224) with a photothermal component made of polypyrrole (PPy) by three distinct methodologies, resulting in micromotors with different motion behavior and catalytic performance. Impressively, the optimized MOFtors display exceptional maximum velocity of 1305 ± 327 µm s-1 under blue light and 2357 ± 453 µm s-1 under UV light. In harsh saline environments, these MOFtors are not only maintain high motility but also exhibit superior tetracycline hydrochloride (TCH) removal efficiency of 3578 ± 510 mg g-1, coupling with sulfate radical-based advanced oxidation processes and peroxymonosulfate. This research underscores the significant potential of highly efficient MOFtors with robust photocatalytic activity in effectively removing TCH in challenging saline conditions, representing a substantial advancement in applying MOFtors within real-world water treatment technologies.

Boosting photothermal conversion through array aggregation of metalloporphyrins in bismuth-based coordination frameworks

Materials capable of efficiently converting near-infrared (NIR) light into heat are highly sought after in biotechnology. In this study, two new three-dimensional (3D) porphyrin-based metal-organic frameworks (MOFs) with a sra-net, viz. CoTCPP-Bi/NiTCPP-Bi, were successfully synthesized. These MOFs feature bismuth carboxylate nodes interconnected by metalloporphyrinic spacers, forming one-dimensional (1D) arrays of closely spaced metalloporphyrins. Notably, the CoTCPP-Bi exhibits an approximate Co⋯C distance of 3 Å, leading to enhanced absorption of NIR light up to 1400 nm due to the presence of strong interlayer van der Waals forces. Furthermore, the spatial arrangement of the metalloporphyrins prevents axial coordination at the centers of porphyrin rings and stabilizes a CoII-based metalloradical. These characteristics promote NIR light absorption and non-radiative decay, thereby improving photothermal conversion efficiency. Consequently, CoTCPP-Bi can rapidly elevate the temperature from room temperature to 190 °C within 30 seconds under 0.7 W cm-2 energy power from 808 nm laser irradiation. Moreover, it enables solar-driven water evaporation with an efficiency of 98.5% and a rate of 1.43 kg m-2 h-1 under 1 sun irradiation. This research provides valuable insights into the strategic design of efficient photothermal materials for effective NIR light absorption, leveraging the principles of aggregation effect and metalloradical chemistry.

Polymer-Supported Pd Nanoparticles for Solvent-Free Hydrogenation

Breaking the trade-off between activity and stability of supported metal catalysts has been a long-standing challenge in catalysis, especially for metal nanoparticles (NPs) with high hydrogenation activity but poor stability. Herein, we report a porous poly(divinylbenzene) polymer-supported Pd NP catalyst (Pd/PDVB) with both high activity and excellent stability for the solvent-free hydrogenation of nitrobenzene, even at ambient temperature (25 °C) and H2 pressure (0.1 MPa). Pd/PDVB gave a turnover frequency as high as 22,632 h-1 at 70 °C and 0.4 MPa, exceeding 5556 h-1 of the classical Pd/C catalyst under equivalent conditions. Mechanistic studies reveal that the polymer support benefits the desorption of the aniline product from the Pd surface, which is crucial for rapid hydrogenation under solvent-free conditions. In addition, the polymer support in Pd/PDVB efficiently hindered Pd leaching, resulting in good stability.

Metal-organic frameworks for organic transformations by photocatalysis and photothermal catalysis

Organic transformation by light-driven catalysis, especially, photocatalysis and photothermal catalysis, denoted as photo(thermal) catalysis, is an efficient, green, and economical route to produce value-added compounds. In recent years, owing to their diverse structure types, tunable pore sizes, and abundant active sites, metal-organic framework (MOF)-based photo(thermal) catalysis has attracted broad interest in organic transformations. In this review, we provide a comprehensive and systematic overview of MOF-based photo(thermal) catalysis for organic transformations. First, the general mechanisms, unique advantages, and strategies to improve the performance of MOFs in photo(thermal) catalysis are discussed. Then, outstanding examples of organic transformations over MOF-based photo(thermal) catalysis are introduced according to the reaction type. In addition, several representative advanced characterization techniques used for revealing the charge reaction kinetics and reaction intermediates of MOF-based organic transformations by photo(thermal) catalysis are presented. Finally, the prospects and challenges in this field are proposed. This review aims to inspire the rational design and development of MOF-based materials with improved performance in organic transformations by photocatalysis and photothermal catalysis.

Photonanozyme-Kras-ribosome combination treatment of non-small cell lung cancer after COVID-19

With the outbreak of the coronavirus disease 2019 (COVID-19), reductions in T-cell function and exhaustion have been observed in patients post-infection of COVID-19. T cells are key mediators of anti-infection and antitumor, and their exhaustion increases the risk of compromised immune function and elevated susceptibility to cancer. Non-small cell lung cancer (NSCLC) is the most common subtype of lung cancer with high incidence and mortality. Although the survival rate after standard treatment such as surgical treatment and chemotherapy has improved, the therapeutic effect is still limited due to drug resistance, side effects, and recurrence. Recent advances in molecular biology and immunology enable the development of highly targeted therapy and immunotherapy for cancer, which has driven cancer therapies into individualized treatments and gradually entered clinicians' views for treating NSCLC. Currently, with the development of photosensitizer materials, phototherapy has been gradually applied to the treatment of NSCLC. This review provides an overview of recent advancements and limitations in different treatment strategies for NSCLC under the background of COVID-19. We discuss the latest advances in phototherapy as a promising treatment method for NSCLC. After critically examining the successes, challenges, and prospects associated with these treatment modalities, their profound prospects were portrayed.

Spin-dependent electrocatalysis

The shift towards sustainable energy requires efficient electrochemical conversion technologies, emphasizing the crucial need for robust electrocatalyst design. Recent findings reveal that the efficiency of some electrocatalytic reactions is spin-dependent, with spin configuration dictating performance. Consequently, understanding the spin's role and controlling it in electrocatalysts is important. This review succinctly outlines recent investigations into spin-dependent electrocatalysis, stressing its importance in energy conversion. It begins with an introduction to spin-related features, discusses characterization techniques for identifying spin configurations, and explores strategies for fine-tuning them. At the end, the article provides insights into future research directions, aiming to reveal more unknown fundamentals of spin-dependent electrocatalysis and encourage further exploration in spin-related research and applications.

Recent Applications of Photothermal Conversion in Organic Synthesis

Photothermal conversion is a novel heating method that has emerged in recent years, wherein certain species can convert light to heat with great efficiency. These photothermal agents have shown immense promise for generating nanoscale thermal gradients under mild, visible light irradiation, providing a pathway for combining photochemistry with thermally driven reactivity. While this novel heating mechanism has been leveraged to great effect for applications such as photothermal therapeutics and steam water purification, it has seen limited use in organic synthesis. This outlook explores instances wherein the photothermal effect was used directly or as a synergistic component to drive organic reactions and postulates how it may be used moving forward.

Unveiling Ru(bpy)3 2+-Encapsulated Zeolite Y as Photocatalyst: Harnessing Photocatalytic Singlet Oxygen Generation for Mustard Gas Simulant Detoxification

This study explores the encapsulation of Ru(bpy)3 2+ within Zeolite Y (ZY) to improve photocatalytic singlet oxygen generation for the degradation of a mustard gas simulant, namely 2-chloroethyl ethyl sulfide (CEES). Mustard gas simulants are known to disrupt several biological processes; thus, their effective degradation is essential. Zeolite Y, with its hierarchical structure and adjustable Si/Al ratios, is an ideal host for Ru(bpy)3 2+, significantly improving its photocatalytic efficiency and stability. It is demonstrated through XRD and spectroscopic analyses that encapsulated Ru(bpy)3 2+ maintains its structural and photophysical properties, which are essential for generating singlet oxygen. Ru(bpy)3(1.0) loaded ZY(15) (where 1.0 and 15 represent the encapsulated amount of Ru(bpy)3 2+ and Si/Al ratio, respectively) outperforms other investigated photocatalytic systems in the oxidation of CEES, demonstrating high conversion rates and selectivity toward nontoxic sulfoxide products. Immobilization of Ru(bpy)3 2+-encapsulated zeolite Y onto cotton fabric results in effective degradation of CEES. The experimental results, validated by theoretical calculations, indicate an improved oxygen affinity and accessibility in zeolites with higher Si/Al ratios. This study advances the design of photocatalytic materials for environmental and defense applications, providing sustainable solutions for hazardous chemical degradation.

Curved Structure Regulated Single Metal Sites for Advanced Electrocatalytic Reactions

Curved surface with defined local electronic structures and regulated surface microenvironments is significant for advanced catalytic engineering. Since single-atom catalysts are highly efficient and active, they have attracted much attention in recent years. The curvature carrier has a significant effect on the electronic structure regulation of single-atom sites, which effectively promote the catalytic efficiency. Here, the effect of the curvature structure with exposed metal atoms for catalysis is comprehensively summarized. First, the substrates with curvature features are reviewed. Second, the applications of single-atom catalysts containing curvature in a variety of different electrocatalytic reactions are discussed in depth. The impact of curvature effects in catalytic reactions is further analyzed. Finally, prospects and suggestions for their application and future development are presented. This review paves the way for the construction of high curvature-containing surface carriers, which is of great significance for single-atom catalysts development.

A Porphyrin-Faced Zn8L6 Cage for Selective Oxidation of C(sp3)-H Bonds and Sulfides

Catalytic oxidation of benzyl C-H bonds and sulfides from fuel oils stands as an attractive proposition in the quest for clean energy, yet their simultaneous oxidation with a singular, economically friendly catalyst is not well established. In this work, the combination of a cobalt(II) porphyrin ligand with 2-pyridinecarboxaldehyde and ZnII yielded a Zn8L6 cage (Co cube). The three-dimensional conjugated structure effectively enhances energy transfer efficiency, enabling the Co cube to show a good ability to activate oxygen under light conditions for photooxidation. Moreover, this catalytic system demonstrates high selectivity for the photocatalytic oxidation of C(sp3)-H bonds and sulfides, employing the Co cube as a single component catalyst, molecular oxygen as the oxidant, and activating oxygen into 1O2 under mild reaction conditions. This provides significant insights for organic synthesis and future design of photocatalysts with complex molecular components.

Synergy of Photogenerated Electrons and Holes toward Efficient Photocatalytic Urea Synthesis from CO2 and N2

Directly coupling N2 and CO2 to synthesize urea by photocatalysis paves a sustainable route for urea synthesis, but its performance is limited by the competition of photogenerated electrons between N2 and CO2, as well as the underutilized photogenerated holes. Herein, we report an efficient urea synthesis process involving photogenerated electrons and holes in respectively converting CO2 and N2 over a redox heterojunction consisting of WO3 and Ni single-atom-decorated CdS (Ni1-CdS/WO3). For the photocatalytic urea synthesis from N2 and CO2 in pure water, Ni1-CdS/WO3 attained a urea yield rate of 78 μM h-1 and an apparent quantum yield of 0.15 % at 385 nm, which ranked among the best photocatalytic urea synthesis performance reported. Mechanistic studies reveal that the N2 was converted into NO species by ⋅OH radicals generated from photogenerated holes over the WO3 component, meanwhile, the CO2 was transformed into *CO species over the Ni site by photogenerated electrons. The generated NO and *CO species were further coupled to form *OCNO intermediate, then gradually transformed into urea. This work emphasizes the importance of reasonably utilizing photogenerated holes in photocatalytic reduction reactions.

Photosensitizer-free singlet oxygen generation via a charge transfer transition involving molecular O2 toward highly efficient oxidative coupling of arylamines to azoaromatics

Photosensitizer (PS)-mediated generation of singlet oxygen, O2 (a1Δg) is a well-explored phenomenon in chemistry and biology. However, the requirement of appropriate PSs with optimum excited state properties is a prerequisite for this approach which limits its widespread application. Herein, we report the generation of O2 (a1Δg) via direct charge-transfer (CT) excitation of the solvent-O2 (X3Σg -) collision complex without any PS and utilize it for the catalyst-free oxidative coupling of arylamines to azoaromatics under ambient conditions in aqueous medium. Electron paramagnetic resonance (EPR) spectroscopy revealed the formation of O2 (a1Δg) upon direct excitation with 370 nm light. The present approach shows broad substrate scope, remarkably fast reaction kinetics (90 and 40 min under an open and O2 atm, respectively), high selectivity (100%), and excellent yields (up to 100%), and works well for both homo- and hetero-coupling of arylamines. The oxidative coupling of arylamines was found to proceed through the generation of amine radicals via electron transfer (ET) from amines to O2 (a1Δg). Notably, electron-rich amines show higher yields of azo products compared to electron-deficient amines. Detailed mechanistic investigations using various spectroscopic tools revealed the formation of hydrazobenzene as an intermediate along with superoxide radicals which subsequently transform to hydrogen peroxide. The present study is unique in the way that molecular O2 simultaneously acts as a light-absorbing chromophore (solvent-O2 complex) as well as an efficient oxidant (O2 (a1Δg)) in the same reaction. This is the first report on the efficient, selective, and sustainable synthesis of azo compounds in aqueous medium under an ambient atmosphere without any PCs/PSs and paves the way for further in-depth understanding of the chemical reactivity of O2 (a1Δg) generated directly via CT excitation of the solvent-O2 complex toward various photochemical and photobiological transformations.

Bioprotective Respirator Assembled by Defective Carbon Nitride for Long-Term Light Triggered Health Protection

Wearing face masks is the best way to stop the spread of respiratory infections. However, if masks are not sterilized, changing them too frequently can actually increase the risk of cross-contamination. Herein, the construction of an antipathogen photocatalytic mask with carbon vacancy-modified carbon nitride nanosheets (g-C3N4-VC Ns) coated on the non-woven fabrics of the out layer of the mask, offering effective and long-term protection against damaging pathogens when exposed to light is reported. The introduced carbon vacancies are found capable of creating energy-disordered sites and inducing energetic electric force to overcome the Coulomb interactions between electron-hole pairs, thus promoting the electron-hole separation to achieve a high generation of reactive oxygen species (ROS). Thanks to its high activity in generating ROS upon exposure to light, the as-prepared photocatalytic mask shows high pathogen sterilization performance. This, in turn, prolongs the mask's protective lifetime, decreases the need for regular replacement, and decreases medical waste production. The work demonstrated here opens new viewpoints in designing pathogens biocidal protective devices for health protection, offering significant promise in specific environment self-protection.

Hydrogen-Bond-Enhanced Photoreforming of Biomass Furans over a Urea-Incorporated Cu(II) Porphyrin Framework

Solar-driven upgrading of biomass-derived 5-hydroxylmethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) holds great promise for sustainable production of bio-plastics and resins. However, the process is limited by poor selectivity and sluggish kinetics due to the vertical coordination of HMF at relatively strong metal sites. Here, we purposely developed a Cu(II) porphyrin framework featuring side-chain incorporated urea linkages, denoted as TBUPP-Cu MOF, to render HMF a weak hydrogen bond at the urea site and flat adsorption via π-π stacking with the benzene moiety. The unique configuration promotes the approaching of -CHO of HMF to the photoexcited porphyrin ring towards kinetically and thermodynamically favourable intermediate formation and subsequent desorption. The charge localisation and orbital energy alignment enable the selective activation of O2 over the porphyrin to generate ⋅O2 - and 1O2 instead of highly oxidative H2O2 and ⋅OH via spin-flip electron transfer, which drive the ambient oxidation of proximal -CHO. The effective utilisation of redox species and circumvented over-oxidation facilitate a FDCA selectivity of >90 % with a high turnover number of 193 molHMF molCu -1. The facile purification of high-purity FDCA and zero-waste recycling of intermediates and durable catalyst feature TBUPP-Cu MOF a promising photo-oxidation platform towards net-zero biorefining and organic transformations.

Directional Formation of Reactive Oxygen Species Via a Non-Redox Catalysis Strategy That Bypasses Electron Transfer Process

A broad range of chemical transformations driven by catalytic processes necessitates the electron transfer between catalyst and substrate. The redox cycle limitation arising from the inequivalent electron donation and acceptance of the involved catalysts, however, generally leads to their deactivation, causing substantial economic losses and environmental risks. Here, a "non-redox catalysis" strategy is provided, wherein the catalytic units are constructed by atomic Fe and B as dual active sites to create tensile force and electric field, which allows directional self-decomposition of peroxymonosulfate (PMS) molecules through internal electron transfer to form singlet oxygen, bypassing the need of electron transfer between catalyst and PMS. The proposed catalytic approach with non-redox cycling of catalyst contributes to excellent stability of the active centers while the generated reactive oxygen species find high efficiency in long-term catalytic pollutant degradation and selective organic oxidation synthesis in aqueous phase. This work offers a new avenue for directional substrate conversion, which holds promise to advance the design of alternative catalytic pathways for sustainable energy conversion and valuable chemical production.

Recent Advances in Understanding of the Singlet Oxygen in Energy Storage and Conversion

Singlet oxygen (term symbol 1Δg, hereafter 1O2), a reactive oxygen species, has recently attracted increasing interest in the field of rechargeable batteries and electrocatalysis and photocatalysis. These sustainable energy conversion and storage technologies are of vital significance to replace fossil fuels and promote carbon neutrality and finally tackle the energy crisis and climate change. Herein, the recent progresses of 1O2 for energy storage and conversion is summarized, including physical and chemical properties, formation mechanisms, detection technologies, side reactions in rechargeable batteries and corresponding inhibition strategies, and applications in electrocatalysis and photocatalysis. The formation mechanisms and inhibition strategies of 1O2 in particular aprotic lithium-oxygen (Li-O2) batteries are highlighted, and the applications of 1O2 in photocatalysis and electrocatalysis is also emphasized. Moreover, the confronting challenges and promising directions of 1O2 in energy conversion and storage systems are discussed.

Recyclable and Stable Porphyrin-Based Self-Assemblies by Electrostatic Force for Efficient Photocatalytic Organic Transformation

Development of efficient, stable, and recyclable photocatalysts for organic synthesis is vital for transformation of traditional thermal organic chemistry into green sustainable organic chemistry. In this work, the study reports an electrostatic approach to assemble meso-tetra (4-sulfonate phenyl) porphyrin (TPPS)tetra (4-sulfonate phenyl) porphyrin (TPPS) as a donor and benzyl viologen (BV) as an acceptor into stable and recyclable photocatalyst for an efficient organic transformation reaction - aryl sulfide oxidation. By use of the electrostatic TPPS-BV photocatalysts, 0.1 mmol aryl sulfide with electron-donating group can be completely transformed into aryl sulfoxide in 60 min without overoxidation into sulfone, rendering near 100% yield and selectivity. The photocatalyst can be recycled up to 95% when 10 mg amount is used. Mechanistic study reveals that efficient charge separation between TPPS and BV results in sufficient formation of superoxide which further reacts with the oxidized sulfide by the photocatalyst to produce the sulfoxide. This mechanistic pathway differs significantly from the previously proposed singlet oxygen-dominated process in homogeneous TPPS photocatalysis.

Pt/Zn-TCPP Nanozyme-Based Flexible Immunoassay for Dual-Mode Pressure-Temperature Monitoring of Low-Abundance Proteins

Pressure and temperature, as common physical parameters, are important for monitoring human health. In contrast, single-mode monitoring is prone to causing experimental errors. Herein, we innovatively designed a dual-mode flexible sensing platform based on a platinum/zinc-meso-tetrakis(4-carboxyphenyl)porphyrin (Pt/Zn-TCPP) nanozyme for the quantitative monitoring of carcinoembryonic antigen (CEA) in biological fluids with pressure and temperature readouts. The Pt/Zn-TCPP nanozyme with catalytic and photothermal efficiencies was synthesized by means of integrating photosensitizers into porous materials. The flexible sensing system after the antigen-antibody reaction recognized the pressure using a flexible skin-like pressure sensor with a digital multimeter readout, whereas the temperature was acquired via the photoheat conversion system of the Pt/Zn-TCPP nanozyme under 808 nm near-infrared (NIR) irradiation using a portable NIR imaging camera on a smartphone. Meanwhile, the dual-mode flexible sensing system was carried out on a homemade three-dimensional (3D)-printed device. Results revealed that the developed dual-mode immunosensing platform could exhibit good pressure and temperature responses within the dynamic range of 0.5-100 ng mL-1 CEA with the detection limits of 0.24 and 0.13 ng mL-1, respectively. In addition, the pressure and temperature were sensed simultaneously without crosstalk interference. Importantly, the dual-mode flexible immunosensing system can effectively avoid false alarms during the measurement, thus providing great potential for simple and low-cost development for point-of-care testing.

Adavosertib-encapsulated metal-organic frameworks for p53-mutated gallbladder cancer treatment via synthetic lethality

Adavosertib (ADA) is a WEE1 inhibitor that exhibits a synthetic lethal effect on p53-mutated gallbladder cancer (GBC). However, drug resistance due to DNA damage response compensation pathways and high toxicity limits further applications. Herein, estrone-targeted ADA-encapsulated metal-organic frameworks (ADA@MOF-EPL) for GBC synthetic lethal treatment by inducing conditional factors are developed. The high expression of estrogen receptors in GBC enables ADA@MOF-EPL to quickly enter and accumulate near the cell nucleus through estrone-mediated endocytosis and release ADA to inhibit WEE1 upon entering the acidic tumor microenvironment. Ultrasound irradiation induces ADA@MOF-EPL to generate reactive oxygen species (ROS), which leads to a further increase in DNA damage, resulting in a higher sensitivity of p53-mutated cancer cells to WEE1 inhibitor and promoting cell death via conditional synthetic lethality. The conditional factor induced by ADA@MOF-EPL further enhances the antitumor efficacy while significantly reducing systemic toxicity. Moreover, ADA@MOF-EPL demonstrates similar antitumor abilities in other p53-mutated solid tumors, revealing its potential as a broad-spectrum antitumor drug.

Triazine Frameworks for the Photocatalytic Selective Oxidation of Toluene

Investigations into the selective oxidation of inert sp3 C-H bonds using polymer photocatalysts under mild conditions have been limited. Additionally, the structure-activity relationship of photocatalysts often remains insufficiently explored. Here, a series of thiophene-based covalent triazine frameworks (CTFs) are used for the efficient and selective oxidation of hydrocarbons to aldehydes or ketones under ambient aerobic conditions. Spectroscopic methods conducted in situ and density functional theory (DFT) calculations revealed that the sulfur atoms within the thiophene units play a pivotal role as oxidation sites due to the generation of photogenerated holes. The effect of photogenerated holes on photocatalytic toluene oxidation was investigated by varying the length of the spacer in a CTF donor-acceptor based photocatalyst. Furthermore, the manipulation of reactive oxygen species was employed to enhance selectivity by weakening the peroxidative capacity. As an illustrative example, this study successfully demonstrated the synthesis of a precursor of the neurological drug AMG-579 using a photocatalytic protocol.

Guest-Regulated Generation of Reactive Oxygen Species from Porphyrin-Based Multicomponent Metallacages for Selective Photocatalysis

The development of novel materials for highly efficient and selective photocatalysis is crucial for their practical applications. Herein, we employ the host-guest chemistry of porphyrin-based metallacages to regulate the generation of reactive oxygen species and further use them for the selective photocatalytic oxidation of benzyl alcohols. Upon irradiation, the sole metallacage (6) can generate singlet oxygen (1O2) effectively via excited energy transfer, while its complex with C70 (6⊃C70) opens a pathway for electron transfer to promote the formation of superoxide anion (O2⋅-), producing both 1O2 and O2⋅-. The addition of 4,4'-bipyridine (BPY) to complex 6⊃C70 forms a more stable complex (6⊃BPY) via the coordination of the Zn-porphyrin faces of 6 and BPY, which drives fullerenes out of the cavities and restores the ability of 1O2 generation. Therefore, benzyl alcohols are oxidized into benzyl aldehydes upon irradiation in the presence of 6 or 6⊃BPY, while they are oxidized into benzoic acids when 6⊃C70 is employed as the photosensitizing agent. This study demonstrates a highly efficient strategy that utilizes the host-guest chemistry of metallacages to regulate the generation of reactive oxygen species for selective photooxidation reactions, which could promote the utilization of metallacages and their related host-guest complexes for photocatalytic applications.

Visible Light-Mediated Selective Aerobic Oxidation of Alcohols Catalyzed by Disulfide in Batch and Flow

Selective aerobic oxidation of alcohols in batch and flow can be realized under light irradiation, utilizing disulfide as the photocatalyst, and a variety of primary and secondary alcohols were converted to the corresponding aldehydes or ketones in up to 99% yield and high selectivity. The reaction efficiency could be increased even further by combining a continuous-flow strategy. Detailed mechanistic studies have also been achieved to determine the role of oxygen and disulfides in this oxidation.

Metal-organic-framework-confined quantum dots enhance photocurrent signals: A molecularly imprinted photoelectrochemical cathodic sensor for rapid and sensitive tetracycline detection

BACKGROUND

Tetracycline (TC), a cost-effective broad-spectrum antibacterial drug, has been excessively utilized in the livestock and poultry industry, leading to a serious overabundance of TC in livestock wastewater. However, conventional analytical methods such as liquid chromatography and gas chromatography face challenges in achieving sensitive detection of trace amounts of TC in complex substrates. Therefore, it is imperative to develop a highly sensitive and anti-interference analytical method for the detection of tetracycline in livestock wastewater.

RESULTS

A porphyrin-based MOF (PCN-224)-confined carbon dots (CDs) material (CDs@PCN-224) was synthesized by a "bottle-around-ship" strategy. The reduced carrier migration distance is conducive to the separation of electron-hole pairs and enhanced the photocurrent signal due to the tight coupling of CDs and PCN-224. Further, molecularly imprinted polymer (MIP) was synthesized by rapid in-situ UV-polymerization and employed as a recognition element. The specific recognition of the target by imprinted cavities blocks electron transfer, resulting in a "turn off" response signal, thus realizing the selective detection of TC. Under optimal conditions, the constructed MIP-PEC cathodic sensor detected 1.00 × 10-12 M to 1.00 × 10-7 M of TC sensitively, with a limit of detection of 3.72 × 10-13 M. In addition, the proposed MIP-PEC sensor demonstrated good TC detection performance in actual livestock wastewater.

SIGNIFICANCE

The strategy based on MOF pore-confined quantum dots can effectively enhance the photocurrent response of the photosensitive substrate. Simultaneously, the MIP constructed by in-situ rapid UV-polymerization showed excellent anti-interference and reusable properties. This work provides a promising MIP-PEC cathodic sensing method for the rapid and sensitive detection of antibiotics in complex-matrix environmental samples.

{Ru(C6 H6 )}-Decorating Heteropolymolybdate for Highly Activity Photocatalytic Oxidation of Benzyl Alcohol to Benzaldehyde

An unclassical structure of {Ru(C6 H6 )}-based polyoxometalate, Cs6 H4 [Te2 Mo12 O46 {Ru(C6 H6 )}] ⋅ 16.5H2 O (1), has been successfully constructed from {Te2 Mo12 O46 }-type heteropolymolybdate and {Ru(C6 H6 )} group, which structure type was discovered for the first time. Compound 1 not only possesses strong light-harvesting ability, but also exhibits high carrier separation efficiency and lower charge transfer resistance. Under visible light irradiation, compound 1 displayed excellent catalytic activity and circularity in the conversion of benzyl alcohol to benzaldehyde (yield=94 %; turnover number=500; turnover frequency=20.8 h-1 ). Finally, the electron paramagnetic resonance measurement and energy level matching analysis provide theoretical basis for the derivation of the reaction mechanism.

Fe-ZSM-5 zeolite catalyst for heterogeneous Fenton oxidation of 1,4-dioxane: effect of Si/Al ratios and contributions of reactive oxygen species

Heterogeneous Fenton oxidation using traditional catalysts with H2O2 for the degradation of 1,4-dioxane (1,4-DX) still presents challenge. In this study, we explored the potential of Fe-ZSM-5 zeolites (Fe-zeolite) with three Si/Al ratios (25, 100, 300) as heterogeneous Fenton catalysts for the removal of 1,4-DX from aqueous solution. Fe2O3 or ZSM-5 alone provided ineffective in degrading 1,4-DX when combined with H2O2. However, the efficient removal of 1,4-DX using H2O2 was observed when Fe2O3 was loaded on ZSM-5. Notably, the Brønsted acid sites of Fe-zeolite played a crucial role during the degradation of 1,4-DX. Fe-zeolites, in combination with H2O2, effectively removed 1,4-DX via a combination of adsorption and oxidation. Initially, Fe-zeolites demonstrated excellent affinity for 1,4-DX, achieving adsorption equilibrium rapidly in about 10 min, followed by effective catalytic oxidative degradation. Among the Fe-ZSM-5 catalysts, Fe-ZSM-5 (25) exhibited the highest catalytic activity and degraded 1,4-DX the fastest. We identified hydroxyl radicals (·OH) and singlet oxygen (1O2) as the primary reactive oxygen species (ROS) responsible for 1,4-DX degradation, with superoxide anions (HO2·/O2·-) mainly converting into 1O2 and ·OH. The degradation primarily occurred at the Fe-zeolite interface, with the degradation rate constants proportional to the amount of Brønsted acid sites on the Fe-zeolite. Fe-zeolites were effective over a wide working pH range, with alkaline pH conditions favoring 1,4-DX degradation. Overall, our study provides valuable insights into the selection of suitable catalysts for effective removal of 1,4-DX using a heterogeneous Fenton technology.

A Green Environmental Protection Photocatalytic Molecular Reactor for Aerobic Oxidation of Sulfide to Sulfoxide

The design and synthesis of metal-organic frameworks (MOFs) as photocatalytic molecular reactors for varied reactions have drawn great attention. In this work, we designed a novel photoactive perylenediimides-based (PDI) carboxylate ligand N,N'-di(3',3",5',5"-tetrakis(4-carboxyphenyl))-1,2,6,7-tetrachloroperylene-3,4,9,10-tetracarboxylic acid diimide (Cl-PDI-TA) and use it to successfully synthesize a novel Zr(IV)-based MOF 1 constructed from [Zr6 O8 (H2 O)8 ]8+ clusters bridged by Cl-PDI-TA ligands. Structural analysis revealed that Zr-MOF 1 manifests a 3D framework with (4,8)-connected csq topology and possesses triangular channels of ~17 Å and mesoporous hexagonal channels of ~26 Å along c-axis. Moreover, the synthesized Zr-MOF 1 exhibits visible-light absorption and efficient photoinduced free radical generation property, making it a promising photocatalytic molecular reactor. When Zr-MOF 1 was used as a photocatalyst for the aerobic oxidation of sulfides under irradiation of visible light, it could afford the corresponding sulfoxides with high yield and selectivity. Experimental results demonstrated that the substrate sulfides could be fixed in the pores of 1 and directly transformed to the products sulfoxides in the solid state. Furthermore, the mechanism for the photocatalytic transformation was also investigated and the results revealed that the singlet oxygen (1 O2 ) and superoxide radical (O2 ⋅- ) generated by the energy transfer and electron transfer from the photoexcited Zr-MOF to oxidants were the main active species for the catalytic reactions. This work offers a perceptive comprehension of the mechanism in PDI-based MOFs for further study on photocatalytic reactions.

Turning on Singlet Oxygen Generation by Outer-Sphere Microenvironment Modulation in Porphyrinic Covalent Organic Frameworks for Photocatalytic Oxidation

Singlet oxygen (1 O2 ) is ubiquitously involved in various photocatalytic oxidation reactions; however, efficient and selective production of 1 O2 is still challenging. Herein, we reported the synthesis of nickel porphyrin-based covalent organic frameworks (COFs) incorporating functional groups with different electron-donating/-withdrawing features on their pore walls. These functional groups established a dedicated outer-sphere microenvironment surrounding the Ni catalytic center that tunes the activity of the COFs for 1 O2 -mediated thioether oxidation. With the increase of the electron-donating ability of functional groups, the modulated outer-sphere microenvironment turns on the catalytic activity from a yield of nearly zero by the cyano group functionalized COF to an excellent yield of 98 % by the methoxy group functionalized one. Electronic property investigation and density-functional theory (DFT) calculations suggested that the distinct excitonic behaviors attributed to the diverse band energy levels and orbital compositions are responsible for the different activities. This study represents the first regulation of generating reactive oxygen species (ROS) based on the strategy of outer-sphere microenvironment modulation in COFs.

Design of bifunctional ultrathin MnO2 nanofilm with laccase-like activity for sensing environmental pollutants containing phenol groups

Laccase-catalyzed oxidative reactions are increasingly examined as a reliable approach to environmental analysis and remediation, and it is urgent to widen metal category to compensate huge gap in the number of studies on copper- and non-copper laccase mimics. Herein, two-dimensional ultrathin MnO2 nanofilm (Mn-uNF) was designed via a chemical deposition and alkali etching process. Similar to Cu-laccase, Mn-uNF can oxidize phenols via a one-electron-transfer reaction of Mn(III) and accelerate the MnIII/MnIV state cycle through an unconventional oxygen reduction process. The excellent laccase-like performance of Mn-uNF can be ascribed to the abundant atomically dispersed Vo-assisted Mn(III) and surface -OH species, which was confirmed by characterizations and DFT calculation. Further, a facile dual-function colorimetric platform was designed for array sensing of o-, m-, and p-dihydroxybenzene isomers and one-step discrimination of tetracyclines containing phenol groups. These findings provide reasonable guidance for the design of a nanozyme with active Mn sites as a new family member of highly efficient copper-free laccase mimics.

Biomedical Application of Porphyrin-Based Amphiphiles and Their Self-Assembled Nanomaterials

Porphyrins have been vastly explored and applied in many cutting-edge fields with plenty of encouraging achievements because of their excellent properties. As important derivatives of porphyrins, porphyrin-based amphiphiles (PBAs) not only maintain the advanced properties of porphyrins (catalysis, imaging, and energy transfer) but also possess self-assembly and encapsulation capability in aqueous solution. Accordingly, PBAs and their self-assembles have had important roles in diagnosing and treating tumors and inflammation lesions in vivo, but not limited to these. In this article, we introduce the research progress of PBAs, including their constitution, structure design strategies, and performances in tumor and inflammation lesion diagnosis and treatments. On that basis, the defects of synthesized PBAs during their application and the possible effective strategies to overcome the limitations are also proposed. Finally, perspectives on PBAs exploration are updated based on our knowledge. We hope this review will bring researchers from various domains insights about PBAs.

Pt-Se-Bonded Nanoprobe for High-Fidelity Detection of Non-small Cell Lung Cancer and Enhancement of NIR II Photothermal Therapy

Non-small cell lung cancer (NSCLC) accounts for a high proportion of lung cancer cases globally, but early detection remains challenging, and insufficient oxygen supply at tumor sites leads to suboptimal treatment outcomes. Therefore, the development of core-shell Au@Pt-Se nanoprobes (Au@Pt-Se NPs) with peptide chains linked through Pt-Se bonds was designed and synthesized for NSCLC biomarker protein calcium-activated neutral protease 2 (CAPN2) and photothermal therapy (PTT) enhancement. The NP can be specifically cleaved by CAPN2, resulting in fluorescence recovery to realize the detection. The Pt-Se bonds exhibit excellent resistance to biologically abundant thiols such as glutathione, thus avoiding "false-positive" results and enabling precise detection of NSCLC. Additionally, the platinum (Pt) shell possesses catalase-like properties that catalyze the generation of oxygen from endogenous hydrogen peroxide within the tumor, thereby reducing hypoxia-inducible factor-1α (HIF-1α) levels and alleviating the hypoxic environment at the tumor site. The Au@Pt-Se NPs exhibit strong absorption bands, enabling the possibility of PTT in the near-infrared II region (NIR II). This study presents an effective approach for the early detection of NSCLC while also serving as an oxygen supplier to alleviate the hypoxic environment and enhance NIR II PTT.

Spontaneous generation of singlet oxygen on microemulsion-derived manganese oxides with rich oxygen vacancies for efficient aerobic oxidation

Developing innovative catalysts for efficiently activating O2 into singlet oxygen (1O2) is a cutting-edge field with the potential to revolutionize green chemical synthesis. Despite its potential, practical implementation remains a significant challenge. In this study, we design a series of nitrogen (N)-doped manganese oxides (Ny-MnO2, where y represents the molar amount of the N precursor used) nanocatalysts using compartmentalized-microemulsion crystallization followed by post-calcination. These nanocatalysts demonstrate the remarkable ability to directly produce 1O2 at room temperature without the external fields. By strategically incorporating defect engineering and interstitial N, the concentration of surface oxygen atoms (Os) in the vicinity of oxygen vacancy (Ov) reaches 51.1% for the N55-MnO2 nanocatalyst. This feature allows the nanocatalyst to expose a substantial number of Ov and interstitial N sites on the surface of N55-MnO2, facilitating effective chemisorption and activation of O2. Verified through electron paramagnetic resonance spectroscopy and reactive oxygen species trapping experiments, the spontaneous generation of 1O2, even in the absence of light, underscores its crucial role in aerobic oxidation. Density functional theory calculations reveal that an increased Ov content and N doping significantly reduce the adsorption energy, thereby promoting chemisorption and excitation of O2. Consequently, the optimized N55-MnO2 nanocatalyst enables room-temperature aerobic oxidation of alcohols with a yield surpassing 99%, representing a 6.7-fold activity enhancement compared to ε-MnO2 without N-doping. Furthermore, N55-MnO2 demonstrates exceptional recyclability for the aerobic oxidative conversion of benzyl alcohol over ten cycles. This study introduces an approach to spontaneously activate O2 for the green synthesis of fine chemicals.

Size-Regulated Hole and Triplet Energy Transfer from CdSe Quantum Dots to Organic Acceptors for Enhancing Singlet Oxygen Generation

Triplet energy transfer (TET) from semiconductor quantum dots (QDs) is an emerging strategy for sensitizing molecular triplets that have great potential in many applications. Here, CdSe QDs with varying sizes and 1-pyrenecarboxylic acid (PCA) are selected as the triplet donor and acceptor, respectively, to study the TET and charge transfer dynamics as well as enhanced singlet oxygen (1O2) generation properties. The results from static and transient spectroscopy measurements demonstrate that both the TET and hole transfer occur at the QDs-PCA interface. The observed significant drop in TET efficiency from 52 to 8% with increasing QD size results from the reduced TET driving force between the QDs and PCA, which is further confirmed by the more efficient sensitization of the anthracene derivative with a large TET driving force. In contrast, the hole transfer efficiency displays a small decrease with an increasing QD size due to a slight change in the hole driving force. The sensitized PCA triplets show a good ability of 1O2 generation, and the 1O2 formation rate increases 10-fold as the QD size decreases from 3.3 to 2.4 nm. These findings provide a profound understanding of the TET and hole transfer mechanism from QDs to molecules and are significant in designing efficient 1O2 generation systems based on semiconductor QDs and triplet molecules.

Multifunctional AuPt Nanoparticles for Synergistic Photothermal and Radiation Therapy

Background

Photothermal therapy (PTT) has gained considerable interest as an emerging modality for cancer treatment in recent years. Radiation therapy (RT) has been widely used in the clinic as a traditional treatment method. However, RT and PTT treatments are limited by side effects and penetration depth, respectively. In addition, hypoxia within the tumor can lead to increased resistance to treatment.

Methods

We synthesized multiple sizes of AuPt by modulating the reaction conditions. The smallest size of AuPt was selected and modified with folic acid (FA) for PTT and RT synergy therapy. Various methods including transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FITR) are used to determine the structure and composition of AuPt-FA (AF). In addition, we researched the photothermal properties of AF with IR cameras and infrared lasers. Flow cytometry, colony formation assays, CCK8, and fluorescent staining for probing the treatment effect in vitro. Also, we explored the targeting of AF by TEM and In Vivo Imaging Systems (IVIS). In vivo experiments, we record changes in tumor volume and weight as well as staining of tumor sections (ROS, Ki67, and hematoxylin and eosin).

Results

The AuPt with particle size of 16 nm endows it with remarkably high photothermal conversion efficiency (46.84%) and catalase activity compared to other sizes of AuPt (30 nm and 100 nm). AF alleviates hypoxia in the tumor microenvironment, leading to the production of more reactive oxygen species (ROS) during the treatment. In addition, the therapeutic effect was significantly enhanced by combining RT and PTT, with an apoptosis rate of 81.1% in vitro and an in vivo tumor volume reduction rate of 94.0% in vivo.

Conclusion

These results demonstrate that AF potentiates the synergistic effect of PTT and RT and has the potential for clinical translation.

Reticular framework materials for photocatalytic organic reactions

Photocatalytic organic reactions, harvesting solar energy to produce high value-added organic chemicals, have attracted increasing attention as a sustainable approach to address the global energy crisis and environmental issues. Reticular framework materials, including metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), are widely considered as promising candidates for photocatalysis owing to their high crystallinity, tailorable pore environment and extensive structural diversity. Although the design and synthesis of MOFs and COFs have been intensively developed in the last 20 years, their applications in photocatalytic organic transformations are still in the preliminary stage, making their systematic summary necessary. Thus, this review aims to provide a comprehensive understanding and useful guidelines for the exploration of suitable MOF and COF photocatalysts towards appropriate photocatalytic organic reactions. The commonly used reactions are categorized to facilitate the identification of suitable reaction types. From a practical viewpoint, the fundamentals of experimental design, including active species, performance evaluation and external reaction conditions, are discussed in detail for easy experimentation. Furthermore, the latest advances in photocatalytic organic reactions of MOFs and COFs, including their composites, are comprehensively summarized according to the actual active sites, together with the discussion of their structure-property relationship. We believe that this study will be helpful for researchers to design novel reticular framework photocatalysts for various organic synthetic applications.

Selective aerobic coupling of amines to imines using solar spectrum-responsive flower-like Nen-graphene quantum dots (GQDs) decorated with 2, 4-dinitrophenylhydrazine (PH) as a photocatalyst

Indeed, the development of ecologically benign molecular fabrication methods for highly efficient graphene quantum dots-based photocatalysts is of great significant. Graphene quantum dots-based photocatalysts have promising applications in various field, including environmental remediation, energy conversion, and splitting of water. However, ensuring resource reusability and minimizing the environmental impact are crucial considerations in the development. From this perspective, attention has also been paid to the creation of easy to make solar light harvesting graphene quantum dots-based photocatalysts for synthesising pharmaceuticals and functional imines compounds. Imines are excellent significant building blocks in pharmaceutical chemistry and excellent examples of these valuable compounds' synthetic intermediates, and the environmentally friendly oxidative synthesis of imines from amines. Therefore, herein, we designed a facile and efficient condensation route to synthesize the Nen-GQDs@PH photocatalyst. This route involves coupling of 2,4-dinitrophenylhydrazine (PH) with nitrogen-enriched graphene quantum dots (Nen-GQDs). The Nen-GQDs@PH as photocatalyst functions in a highly selective and efficient manner, leading to high amines conversion efficiency to imines (95%). Our results highlight a novel and environmentally safe approach for generating highly selective imines from various types of amines, setting a new benchmark in the current research field.

Site Engineering of Covalent Organic Frameworks for Regulating Peroxymonosulfate Activation to Generate Singlet Oxygen with 100 % Selectivity

Singlet oxygen (1 O2 ) is an excellent reactive oxygen species (ROSs) for the selective conversion of organic matter, especially in advanced oxidation processes (AOPs). However, due to the huge dilemma in synthesizing single-site type catalysts, the control and regulation of 1 O2 generation in AOPs is still challenging and the underlying mechanism remains largely obscure. Here, taking advantage of the well-defined and flexibly tunable sites of covalent organic frameworks (COFs), we report the first achievement in precisely regulating ROSs generation in peroxymonosulfate (PMS)-based AOPs by site engineering of COFs. Remarkably, COFs with bipyridine units (BPY-COFs) facilitate PMS activation via a nonradical pathway with 100 % 1 O2 , whereas biphenyl-based COFs (BPD-COFs) with almost identical structures activate PMS to produce radicals (⋅OH and SO4 .- ). The BPY-COFs/PMS system delivers boosted performance for selective degradation of target pollutants from water, which is ca. 9.4 times that of its BPD-COFs counterpart, surpassing most reported PMS-based AOPs systems. Mechanism analysis indicated that highly electronegative pyridine-N atoms on BPY-COFs provide extra sites to adsorb the terminal H atoms of PMS, resulting in simultaneous adsorption of O and H atoms of PMS on one pyridine ring, which facilitates the cleavage of its S-O bond to generate 1 O2 .

Acid-induced tubular g-C3N4 for the selective generation of singlet oxygen by energy transfer: Implications for the photocatalytic degradation of parabens in real water environments

Parabens are widely present in aquatic environments and pose potential health risk. Although great progress has been made in the field of the photocatalytic degradation of parabens, the powerful Coulomb interactions between electrons and holes are the major limitations to photocatalytic performance. Hence, acid-induced tubular g-C3N4 (AcTCN) was prepared and applied for the removal of parabens from a real water environment. AcTCN not only increased the specific surface area and light absorption capacity, but also selectively generated 1O2 via an energy transfer-mediated oxygen activation pathway. The 1O2 yield of AcTCN was 11.8 times higher than that of g-C3N4. AcTCN exhibited remarkable removal efficiencies for parabens depending on the length of the alkyl group. Furthermore, the rate constants (k values) of parabens in ultrapure water were higher than those in tap and river water because of the presence of organic and inorganic species in real water environments. Two possible pathways for the photocatalytic degradation of parabens are proposed based on the identification of intermediates and theoretical calculations. In summary, this study offers theoretical support for the efficient enhancement of the photocatalytic performance of g-C3N4 for the removal of parabens in real water environments.

Fe3 O4 and bimetal-organic framework Zn/Mg composite peroxide-like catalyze luminol chemiluminescence for specific measurement of atropine in Datura plant

Atropine (AT) is an anticholinergic drug. AT is abundantly in Datura plant seeds. Fe3 O4 @Zn/Mg MOF (Fe3 O4 @MOF) composite was synthesized. The compound had a high peroxidase-like activity in a chemiluminescence (CL) reaction. Addition of AT quenched CL. The linear range and limit of detection were 5-600 μg L-1 and 2 × 10-2  μg L-1 . This method is fast, reversible, and selective, without biodegradability effects, high accuracy, and precision for measuring AT in the Datura plant.

A Photosensitizing Metal-Organic Framework as a Tandem Reaction Catalyst for Primary Alcohols from Terminal Alkenes and Alkynes

Owing to the wide and growing demand for primary alcohols, the development of efficient catalysts with high regioselectivity remains a worthwhile pursuit. However, according to Markovnikov's rule, it is a challenge to obtain primary alcohols with high yields and regioselectivity from terminal alkenes or alkynes. Herein, we report the synthesis of a photosensitizing two-dimensional (2D) metal-organic framework (MOF) from cyclic trinuclear copper(I) units (Cu-CTUs) and a boron dipyrro-methene (Bodipy) ligand. The MOF features broadband light absorption, excellent photoinduced charge separation efficiency, and photochemical properties. By integrating the copper-catalyzed hydroboration and photocatalyzed aerobic oxidation, it can catalyze terminal alkenes and alkynes to produce primary alcohols via a one-pot tandem reaction with excellent regioselectivity, good overall yields in two-step reactions (up to 85 %), broad substrate compatibility (32 examples) and good reusability under mild conditions.

Surface ligand-assisted synthesis and biomedical applications of metal-organic framework nanocomposites

Metal-organic framework (MOF) nanocomposites have recently gained intensive attention for biosensing and disease therapy applications owing to their outstanding physiochemical properties. However, the direct growth of MOF nanocomposites is usually hindered by the mismatched lattice in the interface between the MOF and other nanocomponents. Surface ligands, molecules with surfactant-like properties, are demonstrated to exhibit the robust capability to modify the interfacial properties of nanomaterials and can be utilized as a powerful strategy for the synthesis of MOF nanocomposites. Besides this, surface ligands also exhibit significant functions in the morphological control and functionalization of MOF nanocomposites, thus greatly enhancing their performance in biomedical applications. In this review, the surface ligand-assisted synthesis and biomedical applications of MOF nanocomposites are comprehensively reviewed. Firstly, the synthesis of MOF nanocomposites is discussed according to the diverse roles of surface ligands. Then, MOF nanocomposites with different properties are listed with their applications in biosensing and disease therapy. Finally, current challenges and further directions of MOF nanocomposites are presented to motivate the development of MOF nanocomposites with elaborate structures, enriched functions, and excellent application prospects.

Photocatalytic Cascade Reaction Driven by Directed Charge Transfer over VS -Zn0.5 Cd0.5 S/GO for Controllable Benzyl Oxidation

Photocatalysis is an important technique for synthetic transformations. However, little attention has been paid to light-driven synergistic redox reactions for directed synthesis. Herein, the authors report tunable oxidation of benzyl to phenylcarbinol with the modest yield (47%) in 5 h via singlet oxygen (¹ O₂ ) and proton-coupled electron transfer (PCET) over the photocatalyst Zn_0.5 Cd_0.5 S (ZCS)/graphene oxide (GO) under exceptionally mild conditions. Theoretical calculations indicate that the presence of S vacancies on the surface of ZCS/GO photocatalyst is crucial for the adsorption and activation of O₂ , successively generating the superoxide radical (^• O₂ ^- ) and ¹ O₂ , attributing to the regulation of local electron density on the surface of ZCS/GO and photogenerated holes (h⁺ ). Meanwhile, accelerated transfer of photogenerated electrons (e^- ) to GO caused by the π-π stacking effect is conducive to the subsequent aldehyde hydrogenation to benzyl alcohol rather than non-selective oxidation of aldehyde to carboxylic acid. Anisotropic charge transport driven by the built-in electric field can further promote the separation of e^- and h⁺ for multistep reactions. Promisingly, one-pot photocatalytic conversion of p-xylene to 4-methylbenzyl alcohol is beneficial for reducing the harmful effects of aromatics on human health. Furthermore, this study provides novel insights into the design of photocatalysts for cascade reactions.

Chelated Ion-Exchange Strategy toward BiOCl Mesoporous Single-Crystalline Nanosheets for Boosting Photocatalytic Selective Aromatic Alcohols Oxidation

The photoresponse and photocatalytic efficiency of bismuth oxychloride (BiOCl) are greatly limited by rapid recombination of photogenerated carriers. The construction of porous single-crystal BiOCl photocatalyst can effectively alleviate this issue and provide accessible active sites. Herein, a facile chelated ion-exchange strategy is developed to synthesize BiOCl mesoporous single-crystalline nanosheets (BiOCl MSCN) using acetic acid and ammonia solution respectively as chelating agent and ionization promoter. The strong chelation between acetate ions and Bi³⁺ ions introduces acetate ions into the precipitated product to exchange with Cl^- ions, resulting in large lattice mismatch, strain release, and formation of void-like mesopores. The prepared BiOCl MSCN photocatalyst exhibits excellent catalytic performance with 99% conversion and 98% selectivity for oxidation of benzyl alcohol to benzaldehyde and superior general adaptability for various aromatic alcohols. The theoretical calculations and characterizations confirm that the superior performance is mainly attributed to the abundant oxygen vacancies, plenty of accessible adsorption/active sites and fast charge transport path without grain boundaries.

Mixed-Component Metal-Organic Framework for Boosting Synergistic Photoactivation of C(sp3)-H and Oxygen

Synergistic catalysis is an efficient and powerful strategy for simultaneously activating reactants by multiple active sites to promote the efficiency of difficult and challenging catalytic reactions. Meanwhile, enzymes with multi-active-site synergistic catalytic properties possessing high efficiency and high selectivity have become the goal pursued in the field of catalytic chemistry in recent years. Metal-organic frameworks (MOFs), as an effective heterogeneous catalytic platform, that can integrate multiple active sites for synergistic catalysis like enzymatic systems have recently attracted interest. Herein, we report a doubly interpenetrated metal-organic framework with dual active sites, Mn^III-porphyrin sites to directly activate molecular oxygen and fluoren-9-one sites to produce a hydrogen atom transfer (HAT) agent by the proton-coupled electron transfer (PCET) process to simultaneously activate inert C(sp³)-H bonds for efficient inert C(sp³)-H bond oxidation under mild conditions. The bifunctional mixed-component MOF structure forced the two catalytic sites closer together to a more suitable distance, exhibiting high photocatalytic activity for inert C(sp³)-H bond oxidation with almost unique selectivity under mild conditions. The density functional theory (DFT) calculation of free energy during the whole catalytic process demonstrated that it is likely that the synergistic catalytic process occurred in the interframework to accelerate the catalytic reaction. The assembling mixed-component MOF for synergistic catalysis would be a prospective approach for the inert C(sp³)-H photoactivation and functionalization.

Constructing a Photocatalyst for Selective Oxidation of Benzyl Alcohol to Benzaldehyde by Photo-Fenton-like Catalysis

A photoactive metal-organic framework (MOF), [K(H₂O)][Cu(DPNDI)][Cu(DPNDI)(CH₃CN)(H₂O)] [Cu_1.5(DPNDI)_1.5H_1.5P₂W₁₈O₆₂]·2H₂O (Cu(Ι)W-DPNDI), was prepared by combining a functional photosensitizer N, N'-bis(4-pyridylmethyl)naphthalene diimide (DPNDI), copper(I) ions, and an oxidation catalyst [P₂W₁₈O₆₂]^6- into a single framework via a hydrothermal process. Cu(Ι)W-DPNDI exhibited a stable structure, strong light absorption capacity, a suitable band gap, and photoelectric properties, which provided favorable conditions for photocatalysis. In the confined space, the well-aligned Cu(I) ions and POM polyanions played a synergetic effect in the electron-transfer process and reactive oxygen species generation. By coupling photocatalysis and heterogeneous Fenton-like catalysis, Cu(Ι)W-DPNDI displayed high efficiency for the selective oxidation of aromatic alcohols, with up to >99% selectivity and 75% yield.

Ultrasound-triggered interfacial engineering-based microneedle for bacterial infection acne treatment

Acne is an inflammatory skin disease mainly caused by Propionibacterium acnes, which can cause local inflammatory reactions and develop into chronic inflammatory diseases in severe cases. To avoid the use of antibiotics and to effectively treat the site of acne, we report a sodium hyaluronate microneedle patch that mediates the transdermal delivery of ultrasound-responsive nanoparticles for the effective treatment of acne. The patch contains nanoparticles formed by zinc porphyrin-based metal-organic framework and zinc oxide (ZnTCPP@ZnO). We demonstrated activated oxygen-mediated killing of P. acnes with an antibacterial efficiency of 99.73% under 15 min of ultrasound irradiation, resulting in a decrease in levels of acne-related factors, including tumor necrosis factor-α, interleukins, and matrix metalloproteinases. The zinc ions up-regulated DNA replication-related genes, promoting the proliferation of fibroblasts and, consequently, skin repair. This research leads to a highly effective strategy for acne treatment through the interface engineering of ultrasound response.

Investigation of the Performance of Heterogeneous MOF-Silver Nanocube Nanocomposites as CO2 Reduction Photocatalysts by In Situ Raman Spectroscopy

Here, we fabricated two different heterogeneous nanocomposites, core-shell MOF-AgNC and corner MOF-AgNC, as photocatalysts for CO₂ conversion by generating metal-organic frameworks (MOFs) on silver nanocube templates. These MOF-AgNC nanocomposites showed good CO₂ adsorption features and high CO₂ reduction reactivity. The performances of these MOF-AgNC nanocomposites in CO₂ adsorption and CO₂ reduction reactions can be characterized by in situ Raman spectrum measurement. The corner MOF-AgNC nanocomposite exhibited a faster CO₂ adsorption rate than the core-shell MOF-AgNC nanocomposite, which was due to the higher surface area/volume ratio of the MOF in corner MOF-AgNC. The CO₂ reaction reactivity and mechanisms (products of the reaction) of CO₂ reduction also depended on the morphologies of MOF-AgNC nanocomposites, which were caused by different reaction environments at the interface between the MOF and AgNCs. The CO₂ reduction reactivity of MOF-AgNC nanocomposites also exhibited high sensitivity to the irradiation intensity and wavelength, which was caused by the variation of the number of hot electrons and their positions in AgNCs with the irradiation intensity and irradiation wavelength, respectively. This method for the synthesis of heterogeneous nanocomposites should make it possible to design photocatalysts for various reactions by carefully designing the morphology and composition of nanocomposites.