Visible light to the second near-infrared light-harvesting donor-acceptor1-donor-acceptor2-type terpolymers for boosted photocatalytic hydrogen evolution via dual-sulfone-acceptor engineering

Developing visible to near-infrared light-absorbing conjugated polymer photocatalysts is crucial for enhancing solar energy utilization efficiency, as most conjugated organic polymers only absorb light in the visible range. In this work, we firstly developed a novel thiophene S,S-dioxide (TDO) monomer with the stronger electron-withdrawing character, and then prepared a series of donor-acceptor1-donor-acceptor2-type (D-A1-D-A2-type) conjugated terpolymers (THTDB-1-THTDB-5) by statistically adjusting the molar ratio of two sulfone-based acceptor monomers, dibenzothiophene-S,S-dioxide (BTDO, A1) and TDO (A2). These terpolymers demonstrate a gradually expanding absorption range from visible light to the second near-infrared (Vis-to-NIR-II) region with the gradual increase of the TDO contents in the polymer skeleton, showcasing excellent absorption properties and efficient light-capturing capabilities. The optimized D-A1-D-A2 polymer photocatalyst THTDB-4 exhibits a high hydrogen evolution rate of 21.27 mmol g-1 h-1 under visible light without any co-catalyst. The dual-sulfone-acceptor engineering offers a viable approach for developing efficient the longer Vis-to-NIR-II light-harvesting polymer photocatalysts.

Synergistic Photoelectrochemical and Photocatalytic Properties of the Cobalt Nanoparticles-Embedded TiVO4 Thin Film

To optimize the semiconductor properties of TiVO4 thin films and enhance their performance, we incorporated cobalt nanoparticles as an effective co-catalyst consisting of a non-noble metal. Through an investigation into the impact of cobalt loading on spray pyrolyzed TiVO4 thin films, we observed a significant enhancement in the photoelectrochemical (PEC) performance. This was accomplished by carefully optimizing the concentrations of Co2+ (3 mM) to fabricate a composite electrode, resulting in a higher photocurrent density for the TiVO4:Co photoanode. When an applied potential of 1.23 V (vs RHE) was used, the photocurrent density reached 450 μA/cm2, approximately 5 times higher than that of bare TiVO4. We conducted a thorough characterization of the composite structure and optical properties. Additionally, electrochemical impedance spectroscopy analysis indicated that the TiVO4/Co thin film exhibited a smaller semicircle, indicating a significant improvement in charge transfer at the interface. In comparison to bare TiVO4, the TiVO4/Co composite exhibited a notable improvement in photocatalytic activity when degrading methylene blue (MB) dye, a widely employed model dye. Under light illumination, a TiVO4/Co thin film exhibited a notable dye degradation rate of 97% within a 45 min duration. The scalability of our fabrication method makes it suitable for large-area devices intended for sunlight-driven PEC seawater splitting studies.

One-Step Synthesis of CuxOy/TiO2 Photocatalysts by Laser Pyrolysis for Selective Ethylene Production from Propionic Acid Degradation

In an effort to produce alkenes in an energy-saving way, this study presents for the first time a photocatalytic process that allows for the obtention of ethylene with high selectivity from propionic acid (PA) degradation. To this end, TiO₂ nanoparticles (NPs) modified with copper oxides (Cu_xO_y/TiO₂) were synthetised via laser pyrolysis. The atmosphere of synthesis (He or Ar) strongly affects the morphology of photocatalysts and therefore their selectivity towards hydrocarbons (C₂H₄, C₂H₆, C₄H₁₀) and H₂ products. Specifically, Cu_xO_y/TiO₂ elaborated under He environment presents highly dispersed copper species and favours the production of C₂H₆ and H₂. On the contrary, Cu_xO_y/TiO₂ synthetised under Ar involves copper oxides organised into distinct NPs of ~2 nm diameter and promotes C₂H₄ as the major hydrocarbon product, with selectivity, i.e., C₂H₄/CO₂ as high as 85% versus 1% obtained with pure TiO₂.

Highly crystalline and water-wettable benzobisthiazole-based covalent organic frameworks for enhanced photocatalytic hydrogen production

Two-dimensional covalent organic frameworks are promising for photocatalysis by virtue of their structural and functional diversity, but generally suffer from low activities relative to their inorganic competitors. To fulfill their full potential requires a rational tailoring of their structures at different scales as well as their surface properties. Herein, we demonstrate benzobisthiazole-based covalent organic frameworks as a superior photocatalyst for hydrogen production. The product features high crystallinity with ordered 2.5-nm-wide cylindrical mesopores and great water wettability. These structural advantages afford our polymeric photocatalyst with fast charge carrier dynamics as evidenced by a range of spectroscopic characterizations and excellent catalytic performances when suspended in solution or supported on melamine foams. Under visible-light irradiation, it enables efficient and stable hydrogen evolution with a production rate of 487 μmol h^-1 (or a mass-specific rate of 48.7 mmol g^-1 h^-1)-far superior to the previous state of the art. We also demonstrate that hydrogen production can be stoichiometrically coupled with the oxidation conversion of biomass as exemplified by the conversion of furfuryl alcohol to 2-furaldehyde.

Trends and progress in application of cobalt-based materials in catalytic, electrocatalytic, photocatalytic, and photoelectrocatalytic water splitting

There has been a growing interest in water oxidation in recent two decades. Along with that, remarkable discovery of formation of a mysterious catalyst layer upon application of an anodic potential of 1.13 V vs. standard hydrogen electrode (SHE) to an inert indium tin oxide electrode immersed in phosphate buffer containing Co^(II) ions by Nocera et.al, has greatly attracted researchers interest. These researches have oriented in two directions; one focuses on obtaining better understanding of the reported mysterious catalyst layer, further modification, and improved performance, and the second approach is about designing coordination complexes of cobalt and investigating their properties toward the application in water splitting. Although there have been critical debates on true catalysts that are responsible for water oxidation in homogeneous systems of coordination complexes of cobalt, and the case is not totally closed, in this short review, our focus will be mainly on recent major progress and developments in the design and the application of cobalt oxide-based materials in catalytic, electrocatalytic, photocatalytic, and photoelectrocatalytic water oxidation reaction, which have been reported since pioneering report of Nocera in 2008 (Kanan Matthew and Nocera Daniel in Science 321:1072-1075, 2008).

Defected tungsten disulfide decorated CdS nanorods with covalent heterointerfaces for boosted photocatalytic H2 generation

Owing to their intrinsic and pronounced charge carrier transport when facing the formidable challenge of inhibiting severe surface charge recombination, one-dimensional (1D) CdS nanostructures are promising for advancing high-yield hydrogen production. We herein demonstrate an efficient strategy of boosting interfacial carrier separation by heterostructuring 1D CdS with defective WS₂. This process yields solid covalent interfaces for high flux carrier transfer that differ distinctively from those reported structures with physical contacts. As a nonnoble cocatalyst, WS₂ can accept photogenerated electrons from CdS, and the sulfur vacancies existing at its edges can effectively trap electrons as active sites for H₂ evolution. Moreover, due to its strong negative property, the H⁺ from the aqueous solution can gather around WS₂. WS₂ possesses a lower reaction barrier than CdS, which expedites the kinetic process for the reaction. The optimized sample exhibits a high photocatalytic H₂ evolution rate of 183.4 µmol/h (10 mg photocatalyst), which is as far as we know among the top in the records for CdS-based photocatalysts. We believe this present work will be inspiring in addressing the interfacial charge carrier transfer by constructing covalent heterointerfaces.

Fabrication of TiO2/NiO p-n Nanocomposite for Enhancement Dye Photodegradation under Solar Radiation

A p-n nanocomposite based on TiO2 nanotubes (NTs) and NiO nanoparticles (NPs) was designed and optimized in this study to improve the photocatalytic performance of methylene blue (MB). The hydrothermal technique has been used to produce TiO2/NiO nanocomposites with different NiO NPs weight ratios; 1TiO2:1NiO, 1TiO2:2NiO, and 1TiO2:3NiO. The crystal phase, chemical composition, optical properties, and morphology of TiO2/NiO were explored by various techniques. TiO2 NTs have a monoclinic structure, while NiO NPs have a cubic structure, according to the structural study. The bandgap of TiO2 NTs was reduced from 3.54 eV to 2.69 eV after controlling the NiO NPs weight ratio. The TiO2/2NiO nanocomposite showed the best photodegradation efficiency. Within 45 min of solar light irradiation, the efficiency of MB dye degradation using TiO2/2NiO hits 99.5% versus 73% using pure TiO2 NTs. Furthermore, the catalytic photodegradation efficiency did not deteriorate significantly even after five reusability cycles, intimating the high stability of the TiO2/2NiO nanocomposite. This suggests that the loading of NiO NPs into TiO2 NTs lowers the recombination of photo-produced electron/hole pairs and enlarged solar spectral response range, which results in improved photocatalytic activity. The mechanism of charge transfer in the TiO2/NiO and kinetic models were discussed for the photodegradation of MB.

Preparation of Ni-loaded oxygen-enriched vacancy TiO2−x hierarchical micro-nanospheres and the study of their photocatalytic hydrogen evolution performance

Ni-loaded oxygen-enriched vacancy TiO2−x hierarchical micro-nanospheres were prepared, and the photocatalytic hydrogen production properties were greatly improved due to the synergetic effect between THS, oxygen vacancies and Ni-based promoters.

Bimetallic Ni-Co nanoparticles confined within nitrogen defective carbon nitride nanotubes for enhanced photocatalytic hydrogen production

This work for the first time reports bimetallic Ni-Co and monometallic (Ni and Co) nanoparticles (NPs)-engineered carbon nitride nanotubes with nitrogen vacancies (V-CNNTs) for visible-light photocatalytic H₂ generation application. The bimetallic Ni-Co NPs have an average size of less than 5 nm and are homogenously dispersed along the nanochannels of V-CNNTs. The composition of the bimetallic NPs plays an essential role to maximize photocatalytic activity. With the optimal Ni/Co atom ratio of 3:1, Ni-Co/V-CNNTs nanohybrids yielded a H₂ production rate of 4.19 μmol/h, which is higher than those of monometallic counterparts and V-CNNTs. The intimately loaded Ni-Co NPs and incorporated nitrogen vacancies enhance the photocatalytic performance through extended light absorption, abundant active sites, strong metal-support interaction, and efficient charge carrier transfer along the axial direction. This study presents a stable and highly efficient hybrid as a promising photocatalyst for visible light photocatalytic H₂ production through water splitting.

Magnetically separable type-II semiconductor based ZnO/MoO3 photocatalyst: a proficient system for heteroarenes arylation and rhodamine B degradation under visible light

Shedding light on a magnetically retrievable ZnO/MoO3 photocatalyst that efficiently coupled diazonium substituted arenes with heteroarene substrates along with efficient degradation of toxic Rhodamine B.

Facile preparation of metallic 1T phase molybdenum selenide as cocatalyst coupled with graphitic carbon nitride for enhanced photocatalytic H2 production

Low-cost, highly active and efficient alternative co-catalysts that can replace precious metals such as Au and Pt are urgently needed for photocatalytic hydrogen evolution reaction (HER). Herein, we show that 1T phase MoSe₂ can act as the co-catalyst in the 1T-MoSe₂/g-C₃N₄ composites and we synthesize this composite by a one-step hydrothermal method to promote photocatalytic H₂ generation. Our prepared 1T-MoSe₂/g-C₃N₄ composite exhibits highly enhanced photocatalytic H₂ production compared to that of g-C₃N₄ nanosheets (NSs) only. The 7 wt%-1T-MoSe₂/g-C₃N₄ composite presents a considerably improved photocatalytic HER rate (6.95 mmol·h^-1·g^-1), approximately 90 times greater than that of pure g-C₃N₄ (0.07 mmol·h^-1 g^-1). Moreover, under illumination at λ = 370 nm, the apparent quantum efficiency (AQE) of the 7 wt%-1T-MoSe₂/g-C₃N₄ composite reaches 14.0%. Furthermore, the 1T-MoSe₂/g-C₃N₄ composites still maintain outstanding photocatalytic HER stability.

Interfacial Charge Transport in 1D TiO2 Based Photoelectrodes for Photoelectrochemical Water Splitting

1D nanostructured photoelectrodes are promising for application as photoelectrochemical (PEC) devices for solar energy conversion into hydrogen (H₂ ) owing to the optical, structural, and electronic advantages. Titanium dioxide (TiO₂ ) is the most investigated candidate as a photoelectrode due to its good photostability, low production cost, and eco-friendliness. The obstacle for TiO₂ 's practical application is the inherent wide bandgap (UV-lights response), poor conductivity, and limited hole diffusion length. Here, a comprehensive review of the current research efforts toward the development of 1D TiO₂ based photoelectrodes for heterogeneous PEC water splitting is provided along with a discussion of nanoarchitectures and energy band engineering influences on interfacial charge transfer and separation of 1D TiO₂ composited with different dimensional photoactive materials. The key focus of this review is to understand the charge transfer processes at interfaces and the relationship between photogenerated charge separation and photoelectrochemical performance. It is anticipated that this review will afford enriched information on the rational designs of nanoarchitectures, doping, and heterojunction interfaces for 1D TiO₂ based photoelectrodes to achieve highly efficient solar energy conversion.

M/TiO2 (M = Fe, Co, Ni, Cu, Zn) catalysts for photocatalytic hydrogen production under UV and visible light irradiation

Cu/TiO₂ photocatalysts can be considered a promising low-cost alternative to the well-known Pt/TiO₂ system for hydrogen production under UV-Vis irradiation.

Different performances of Ni3(PO4)2 in TiO2 photocatalysis under aerobic and anaerobic conditions

A nickel phosphate deposited TiO₂ was more photoactive than TiO₂, not only for phenol oxidation under air, but also for proton reduction under N₂. These are due to formation and involvement of highly reactive Ni⁴⁺ and catalytic Ni⁰, respectively.

Nickel clusters on TiO2(110): thermal chemistry and photocatalytic hydrogen evolution of methanol

While nickel clusters, similar as to platinum ones, facilitate the thermal recombination of hydrogen in the photocatalysis of alcohols, they also undergo photocorrosion over time by the formation of carbon deposits.

A Diuranyl(VI) Complex and Its Application in Electrocatalytic and Photocatalytic Hydrogen Evolution from Neutral Aqueous Medium

The reaction of equimolar amounts of UO₂(OAc)₂·2H₂O, 2,6-diformyl-4-methylphenol, and N-(hydroxyethyl)ethylenediamine in methanol affords a dinuclear trans-uranyl(VI) complex of the molecular formula [(UO₂)₂(μ-L)₂] (L^2- = 2-formyl-4-methyl-6-((2-(2-oxidoethylamino)ethylimino)methyl)phenolate) in 65% yield. Detailed structural elucidation of the complex was performed by using single-crystal X-ray crystallographic and spectroscopic studies. In [(UO₂)₂(μ-L)₂], the metal centers are in edge-shared pentagonal-bipyramidal N₂O₅ coordination spheres assembled by the two meridional ONNO-donor bridging L^2- and two pairs of mutually trans oriented oxo groups. The complex is redox active and displays two successive metal-centered one-electron reductions at E_pc = -0.71 and -1.03 V in N,N-dimethylformamide solution. The redox-active complex was used as a heterogeneous catalyst for electrochemical hydrogen evolution from aqueous medium at pH 7 with a turnover frequency (TOF) of 384 h^-1 and a Tafel slope of 274 mV dec^-1. The Faradaic efficiency of [(UO₂)₂(μ-L)₂] was found to be 84%. Beyond the electrocatalytic response, the [(UO₂)₂(μ-L)₂]-TiO₂-N719 composite also exhibited significant heterogeneous photocatalytic hydrogen evolution activity in neutral aqueous medium under visible light and provided a yield of 3439 μmol g_cat^-1 of H₂ in 4 h with a TOF of 172 h^-1 and apparent quantum yield (AQY) of 7.6%.

Making Use of the δ Electrons in K4Mo2(SO4)4 for Visible-Light-Induced Photocatalytic Hydrogen Production

Quadruply bonded dimolybdenum complexes with a σ²π⁴δ² electronic configuration for the ground state have rich metal-centered photochemistry. An earlier study showed that stoichiometric or less amount of molecular hydrogen was produced upon irradiation by ultraviolet light (λ = 254 nm) of K₄Mo₂(SO₄)₄ in sulfuric acid solution, which was attributed to the reductive capability of the ππ* excited state. To make use of the δ electrons for visible-light-induced photocatalytic hydrogen evolution, a multicomponent heterogeneous photocatalytic system containing K₄Mo₂(SO₄)₄ photosensitizer, TiO₂ electron relay, and MoS₂ cocatalyst is designed and tested. With ascorbic acid added as a sacrificial reagent, irradiation by artificial sunlight (AM 1.5) on the reaction in 5 M H₂SO₄ has produced 13 400 μmol g^-1 of molecular hydrogen (based on the Mo₂ complex), which is 30 times higher than the hydrogen yield obtained from the reaction of bare K₄Mo₂(SO₄)₄ with H₂SO₄ under ultraviolet light irradiation. Further improvement of hydrogen evolution is achieved by addition of oxalic acid, along with an electron donor, which gives an additional 50% increase in H₂ yield. Spectroscopic analyses indicate that, in this case, a junction between the Mo₂ complex and TiO₂ is built by the oxalate bridging ligand, which facilitates charge injection and separation from the Mo₂ core. This Mo₂-TiO₂-MoS₂ system has achieved a high hydrogen evolution rate up to 4570 μmol g^-1 h^-1. The efficiency of K₄Mo₂(SO₄)₄ as a metal-centered photosensitizer is also proved by parallel experiments with a dye chromophore, fluorescein, which presents comparable H₂ yields and hydrogen evolution rates. Most importantly, in this study, detailed analyses illustrate that the photocatalytic cycle with hydrogen gas as an outcome of the reaction is established by involvement of the δδ* excited state generated by visible light irradiation. Therefore, this work shows the potential of quadruply bonded Mo₂ complexes as photosensitizers for photocatalytic hydrogen evolution.

Recent Advances in Carbonaceous Photocatalysts with Enhanced Photocatalytic Performances: A Mini Review

Photocatalytic processes based on various semiconductors have been widely utilized in different applications, with great potential for use in environmental pollution remediation and sustainable energy generation. However, critical issues, including low light adsorption capability, wide energy bandgap, and unsatisfactory physicochemical stability still seriously limit the practical applications of photocatalysts. As a solution, the introduction of carbonaceous materials with different structures and properties into a photocatalyst system to further increase the activity has attracted much research attention. This mini review surveys the related literatures and highlights recent progress in the development of carbonaceous photocatalysts, which include various metal semiconductors with activated carbon, carbon dots, carbon nanotubes/nanofibers, graphene, fullerene, and carbon sponges/aerogels. Moreover, graphitic carbon nitride is also discussed as a carbon-rich and metal-free photocatalyst. The recently developed synthesis strategies and proposed mechanisms underlying the photocatalytic activity enhancement for different applications are summarized and discussed. Finally, ongoing challenges and the developmental direction for carbonaceous photocatalysts are proposed.

Simply blending Ni nanoparticles with typical photocatalysts for efficient photocatalytic H2 production

A photocatalytic system construction method of simply blending as-prepared Ni nanoparticles (Ni NPs) with g-C₃N₄ was carried out to greatly improve the photocatalytic activity of g-C₃N₄.

Ultrathin Ni(OH)2 nanosheets: a new strategy for cocatalyst design on CdS surfaces for photocatalytic hydrogen generation

Ultrathin metal materials exhibit quantum size and surface effects that give rise to unique catalytic properties. In this paper, we report a facile liquid synthesis method for polyvinylpyrrolidone (PVP, K30) capped ultrathin Ni(OH)₂ nanosheets with lamellar structure. The as-prepared ultrathin Ni(OH)₂ nanosheets coupled with CdS nanorods exhibit excellent activity in hydrogen generation from water splitting under visible light. The H₂ evolution rate of Ni(OH)₂/CdS, 40.18 mmol h⁻¹ g_Cat.⁻¹ with a quantum efficiency of 66.1% at 420 nm, is ca. 1.5 times that of Pt/CdS with an optimal loading amount (1.25 wt%) under the same reaction conditions. Considering the cost of photocatalysts, the ultrathin Ni(OH)₂ nanosheet coupled CdS photocatalyst may have a promising commercial application in photocatalytic hydrogen production.

In this report, ultrathin Ni(OH)₂ nanosheets coated CdS photocatalyst for photocatalytic hydrogen generation under visible light has been explored.

The recent development of efficient Earth-abundant transition-metal nanocatalysts

Whereas noble metal compounds have long been central in catalysis, Earth-abundant metal-based catalysts have in the same time remained undeveloped. Yet the efficacy of Earth-abundant metal catalysts was already shown at the very beginning of the 20th century with the Fe-catalyzed Haber-Bosch process of ammonia synthesis and later in the Fischer-Tropsch reaction. Nanoscience has revolutionized the world of catalysis since it was observed that very small Au nanoparticles (NPs) and other noble metal NPs are extraordinarily efficient. Therefore the development of Earth-abundant metals NPs is more recent, but it has appeared necessary due to their "greenness". This review highlights catalysis by NPs of Earth-abundant transition metals that include Mn, Fe, Co, Ni, Cu, early transition metals (Ti, V, Cr, Zr, Nb and W) and their nanocomposites with emphasis on basic principles and literature reported during the last 5 years. A very large spectrum of catalytic reactions has been successfully disclosed, and catalysis has been examined for each metal starting with zero-valent metal NPs followed by oxides and other nanocomposites. The last section highlights the catalytic activities of bi- and trimetallic NPs. Indeed this later family is very promising and simultaneously benefits from increased stability, efficiency and selectivity, compared to monometallic NPs, due to synergistic substrate activation.

Insight into the role of UV-irradiation in photothermal catalytic Fischer–Tropsch synthesis over TiO2 nanotube-supported cobalt nanoparticles

To explore an efficient catalytic system with high activity and selectivity is the key to improve Fischer–Tropsch synthesis (FTS) technology and the main focus in the academic field.

Highly Performance Core-Shell TiO2(B)/anatase Homojunction Nanobelts with Active Cobalt phosphide Cocatalyst for Hydrogen Production

In this paper, a highly efficient core-shell structure of TiO2(B)/anatase photocatalyst with CoP cocatalyst has been synthesized via hydrothermal processes and a mechanical milling method. The designed core-shell TiO2(B)/anatase photocatalysts exhibit excellent performance by compared with pure TiO2(B) and anatase phase. With the participation of CoP particles, there is drastically enhanced  photocatalytic activity of TiO2(B)/anatase, and the H2-production rate can be up to 7400 μmol·g-1, which is about 3.2 times higher than TiO2(B)/anatase photocatalyst. The improved activity is attributed to the contribution of the well-matched core-shell structure and cooperative effect of CoP cocatalyst. The photogenerated holes of anatase can migrate more promptly to the adjacent TiO2(B) core than the photogenerated electrons, which result in an accumulation of electrons in the anatase, and CoP nanoparticles can contribute significantly to transferring electrons from the surface of TiO2(A). It was found that the efficient separation of electron-hole pairs greatly improved the photocatalytic hydrogen evolution in water under UV light irradiation.

Superior Photocatalytic H2 Production with Cocatalytic Co/Ni Species Anchored on Sulfide Semiconductor

Downsizing transition metal-based cocatalysts on semiconductors to promote photocatalytic efficiency is important for research and industrial applications. This study presents a novel and facile strategy for anchoring well-dispersed metal species on CdS surface through controlled decarboxylation of the ethylenediaminetetraacetate (EDTA) ligand in the metal-EDTA (M-EDTA) complex and CdS mixture precursor to function as a cocatalyst in the photocatalytic H₂ evolution. Microstructure characterization and performance evaluation reveal that under visible light the resulting pentacoordinated Co(II) and hexacoordinated Ni(II) on CdS exhibits a high activity of 3.1 mmol h^-1 (with turnover frequency (TOF) of 626 h^-1 and apparent quantum efficiency (AQE) of 56.2% at 420 nm) and 4.3 mmol h^-1 (with TOF of 864 h^-1 and AQE of 67.5% at 420 nm), respectively, toward cocatalytic hydrogen evolution, and the cocatalytic activity of such a hexacoordinated Ni(II) even exceeds that of platinum. Further mechanistic study and theoretical modeling indicate that the fully utilized Co(II)/Ni(II) active sites, efficient charge transfer, and favorable kinetics guarantee the efficient activities. This work introduces a promising precursor, i.e., M-EDTA for planting well-dispersed transition metal species on the sulfide supports by a facile wet-chemistry approach, providing new opportunities for photocatalytic H₂ production at the atomic/molecular scale.

Pt-Co Alloys-Loaded Cubic SiC Electrode with Improved Photoelectrocatalysis Property

A novel composite photocatalyst was synthesized by loading 5 wt % of platinum cobalt alloy on 3C-SiC nanowires and powder (Pt-Co-SiC) respectively via a simple polyol reduction method. Pt-Co-SiC were comprehensively characterized by SEM, HRTEM, XRD, PL, and XPS. The results indicated that Pt-Co nanoparticles in the size of 2-5 nm were dispersed homogeneously in the SiC nanowires and powders. The photocurrent response of the Pt-Co-SiC increased remarkably with increasing Pt content and the best performance was observed with the sample of Pt₃Co-SiC. Especially, the Pt₃Co-SiC nanowires photoelectrode exhibited improved cathodic current density (0.14 mA·cm^-2) under the simulated sunlight, which was about 10 times higher than the Pt₃Co-SiC powders. The H₂ production rate for the Pt₃Co-SiC nanowires is 30 times more than that of the pure SiC nanowires. The enhancement of the Pt-Co-SiC properties could be ascribed to the fact that more visible light was harvested and the photogenerated electron and the interfacial electron transfered more easily.

The recent development of efficient Earth-abundant transition-metal nanocatalysts

This review presents the recent remarkable developments of efficient Earth-abundant transition-metal nanocatalysts.

The W@WO3 ohmic contact induces a high-efficiency photooxidation performance

The W@WO₃ Ohmic-type junction exhibits superior mineralization ability for the photocatalytic degradation of acetaldehyde under UV light irradiation.

Ni supported CdIn2S4 spongy-like spheres: a noble metal free high-performance sunlight driven photocatalyst for hydrogen production

We have reported a strategy to develop a high performance photocatalyst based on noble metal free Ni supported CdIn₂S₄ spongy-like spheres for hydrogen evolution under solar light.

Surface and interface design in cocatalysts for photocatalytic water splitting and CO2reduction

This review outlines the recent progress on designing the surface and interface of cocatalysts to create highly efficient photocatalysts for water splitting and CO₂reduction.

Structural design of TiO2-based photocatalyst for H2 production and degradation applications

This review aims to provide a comprehensive and contemporary overview, as well as a guide of the development of new generation TiO₂ based photocatalysts via structural design for improved solar energy conversion technologies.

Decoration of size-tunable CuO nanodots on TiO2 nanocrystals for noble metal-free photocatalytic H2 production

We report a simple yet effective approach for the decoration of the TiO2 nanocrystal surface with size-tunable CuO nanodots for high-performance noble metal-free photocatalytic H2 production. Modification with polyacrylic acid enables the surface of TiO2 nanocrystals to be selectively deposited with Cu(OH)2 nanodots, which can be subsequently converted to CuO through dehydration without changing their morphologies. UV irradiation of the nanocomposite solution in the presence of a hole scavenger produces photogenerated electrons which reduce CuO to metallic Cu nanodots, making them effective co-catalysts in a role similar to Pt for promoting photocatalytic H2 production. Due to the considerably high work function of Cu, the formation of a metal-semiconductor Schottky junction induces efficient charge separation and transfer. As a result, the TiO2 nanocrystals decorated with an optimal amount of CuO nanodots (1.7 wt%) could reach ∼50% of the photocatalytic activity achievable by the Pt-TiO2 counterparts (1 wt%), clearly demonstrating the great potential of such composite catalysts for efficient noble metal-free photocatalytic H2 production.

Earth-abundant cocatalysts for semiconductor-based photocatalytic water splitting

Active and robust cocatalysts constructed from earth-abundant elements greatly contribute to the highly efficient, stable and cost-effective photocatalytic water splitting.

Structure, stability and photocatalytic H2 production by Cr-, Mn-, Fe-, Co-, and Ni-substituted decaniobate clusters

Among the series of early transition-metal-substituted decaniobate ions synthesized and characterized in this paper, Co- or Ni-substituted decaniobates showed enhanced photocatalytic H₂-evolution activity compared to others.

Cobalt sulphide microtube array as cathode in photoelectrochemical water splitting with photoanodes

A CoS microtube electrode catalyses hydrogen evolution efficiently in both neutral and basic aqueous electrolyte solutions. The microtubular CoS electrode was also combined with a hematite photoanode to give a photoelectrochemical water splitting cell.