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Ta3N5 is a promising material for photocatalytic hydrogen production from water because of its suitable band structure for both solar energy collection and overall water splitting, while its application is restricted by severe charge recombination as well as non‐equilibrium redox capabilities. Herein, atomic‐scale N‐doped NaTaO3@Ta3N5 (NNaTaO3@Ta3N5) core‐shell cubes prepared by nitridation of cubic NaTaO3 are reported. The core‐shell heterojunction cubes present efficient and stoichiometric evolution of H2 and O2 from photocatalytic overall water splitting, with a quantum efficiency of 2.18% at 550 nm without any cocatalyst. The success relies on the Ta3N5 shell having a thickness of only ≈5 nm which enables increased lifetimes of the photogenerated charges. Moreover, the core‐shell heterojunction shows a type‐I band alignment that can steer smooth charge flow from NNaTaO3 to Ta3N5, particularly with the assistance of the shared communal Ta atoms at the interface. This efficiency can be further improved to 6.28% by in situ deposition of a Rh@Cr2O3 core‐shell cocatalyst, which is among the highest reported values over Ta3N5‐based photocatalyst. This study offers a promising pathway for the construction of well‐defined heterojunctions with manipulated charge transfer behavior for photocatalytic overall water splitting. [ABSTRACT FROM AUTHOR]

Charge transfer in a semiconductor is crucial for photocatalytic pure water splitting. Herein, we construct a series of P-doped- g -C 3 N 4 /Fe 2 P/red-P (PCN/Fe 2 P/RP) ternary composite by in-situ phosphorization of a Fe 2 O 3 @C/ g -C 3 N 4 heterojunction. The as-prepared composite show substantially improved photocatalytic activity toward pure water splitting under visible light irradiation without adding any noble metal. The optimized composite containing 15 wt% Fe 2 P presents the best activity, with the H 2 production rate of 429 µmol g−1 h−1, which is 107 and 39 times higher than that of pristine g-C 3 N 4 and P doped g -C 3 N 4 (PCN), respectively. This noble-metal-free photocatalyst presents a solar-to-hydrogen conversion efficiency of about 0.2% for pure water splitting. It is found that water splitting proceeds via a two-electron pathway with simultaneous production of H 2 and H 2 O 2. The improvement relies on the formation of intermediate Fe 2 P for rapid Z-scheme electron transfer from the midgap state of PCN to the valence band of RP. This work provides a versatile method for fabricating noble-metal-free photocatalyst with controlled charge transfer behavior for efficient photocatalytic pure water splitting. [Display omitted] • Efficient P-doped- g -C 3 N 4 /Fe 2 P/red-P photocatalyst is successfully prepared. • Photocatalytic pure water splitting is achieved by two-election Z-scheme mechanism. • Fe 2 P acts as an intermediate layer for rapid Z-scheme electron transfer. • Solar-to-hydrogen conversion efficiency of the composite is about 0.2%. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Heterojunction design in a two‐dimensional (2D) fashion has been deemed beneficial for improving the photocatalytic activity of g‐C3N4 because of the promoted interfacial charge transfer, yet still facing challenges. Herein, we construct a novel 2D/2D Cu3P nanosheet/P‐doped g‐C3N4 (PCN) nanosheet heterojunction photocatalyst (PCN/Cu3P) through a simple in‐situ phosphorization treatment of 2D/2D CuS/g‐C3N4 composite for photocatalytic H2 evolution. We demonstrate that the 2D lamellar structure of both CuS and g‐C3N4 could be well reserved in the phosphorization process, while CuS and g‐C3N4 in‐situ transformed into Cu3P and PCN, respectively, leading to the formation of PCN/Cu3P tight 2D/2D heterojunction. Owing to the large contact area provided by intimate face‐to‐face 2D/2D structure, the PCN/Cu3P photocatalyst exhibits significantly enhanced charge separation efficiency, thus achieving a boosted visible‐light‐driven photocatalytic behavior. The highest rate for H2 evolution reaches 5.12 μmol·h–1, nearly 24 times and 368 times higher than that of pristine PCN and g‐C3N4, respectively. This work represents an excellent example in elaborately constructing g‐C3N4‐based 2D/2D heterostructure and could be extended to other photocatalyst/co‐catalyst system. [ABSTRACT FROM AUTHOR]

Z-scheme photocatalysis provides a promising solution to photocatalytic solar water splitting, yet restricted by inferior interfacial charge transfer. Here, we demonstrate a Z-scheme composite photocatalyst made of Fe 2 O 3 , a carbon layer, and g-C 3 N 4 that can achieve efficient hydrogen generation from solar water decomposition. The success relies on in-situ preparation of core-shell Fe 2 O 3 @C structure at the surface of g-C 3 N 4. Carbon as an intermediate layer thus acts as a bridge that significantly accelerates the migration of photogenerated electrons from Fe 2 O 3 conduction band to g-C 3 N 4 valence band. As a result, the highest rate of H 2 generation reaches 5.26 mmol h−1g−1. This activity is approximately 33-time greater than that achieved over pristine g-C 3 N 4 and about 4-time larger than that obtained over a Fe 2 O 3 /g-C 3 N 4 heterojunction without internal carbon layer. This work explicates the potential insight of the composite and paves a promising way to engineer the charge transfer behavior. [Display omitted] • A heterojunction made of Fe 2 O 3 , g-C 3 N 4 , and a carbon interlayer is obtained. • Photocatalytic water splitting proceeds via a Z-scheme mechanism over the catalyst. • The intermediate carbon layer acts as a channel for efficient electron transfer. • The photocatalytic activity for H 2 production is significantly improved. [ABSTRACT FROM AUTHOR]

Artificial photosynthesis, in which solar energy drives CO2 to produce hydrocarbon fuels, is considered an effective way to solve the increasingly serious energy crisis and mitigate the greenhouse effect. Herein, layered porous Ru‐loaded and La‐doped g‐C3N4 nanosheets (Ru‐LGCNs) were prepared by one‐step calcination, followed by in situ photoreduction deposition of Ru. The layered Ru‐LGCN showed excellent photocatalytic CO2 reformation of methane performance under visible light, and the generation rates of CO, CH3CH3, CH3OH and CH3CH(OH)CH3 were 133, 154, 251 and 133 μmol h−1 g−1, respectively. The reason for the enhanced photocatalytic activity of Ru‐LGCN is the synergistic effect of bimetallic Ru and La. It is worth noting that the doped La can provide a good channel for charge transfer between LGCNs and CO2. This change in the charge behavior of the transport path is beneficial to break the C=O bonds on the active site La and generate methyl radicals on Ru, resulting in the generation of C2+ hydrocarbons. [ABSTRACT FROM AUTHOR]

The general moderate reaction condition in solar photocatalytic hydrogen production (i. e., near ambient pressure, room temperature) makes interfacial mass and energy transfer extremely slow, even by employing a cocatalytic material (usually in the form of noble metal nanoparticles or their counterparts). Herein, by fabricating well‐defined Cu@Ni core‐shell nanoplate cocatalyst and further incorporating it with a g‐C3N4 photocatalyst, we demonstrate that interfacial processes could be significantly improved by coupling localized photothermal effect into a cocatalyst. Specifically, Cu nanoplate can induce localized strong hot spots on Ni nanoparticles via a visible‐light‐driven surface plasma resonance effect. As a result, photogenerated electrons transferred from g‐C3N4 to Ni, could be elevated to a more energetic state, leading to a substantially improved photocatalytic activity toward H2 evolution from water. The highest hydrogen generation rate reaches 55 μmol h−1 g−1, 110 times of that pristine g‐C3N4. This work indicates that photoelectric and photothermal effects can be effectively coupled by integrating metal hetero‐nanoparticles. [ABSTRACT FROM AUTHOR]

Although overall water splitting with particulate photocatalysts is considered as an ideal means towards solar-to-hydrogen conversion, practical application of the promising technique is greatly inhibited by the congenital defects including H 2 /O 2 separation and unfavorable four-electron kinetics. In this context, photocatalytic overall water splitting for simultaneous H 2 and H 2 O 2 generation via a two-electron pathway can readily address these issues. Here, we report a novel Co x Ni y P cluster incorporated P-doped g-C 3 N 4 photocatalyst (Co x Ni y P-PCN) by a two-step phosphating method that presents such unique behavior for pure water splitting into stoichiometric H 2 and H 2 O 2. The highest H 2 evolution rate reaches 239.3 μmol h−1 g−1, achieved over the CoNiP–PCN photocatalyst, which is among the best reported activities for overall water splitting. It is found that both P and the cluster cocatalyst are critical to the remarkably improved photocatalytic activity. Specifically, P as a substitution of C in PCN introduces a positive charge center (P+), reinforcing the chemical connection between PCN and CoNiP, in a form of P+-Pδ--Coδ+/Niδ+. This unique bridging effect, together with the extended light absorption by P doping and optimized surface redox potential by cocatalyst integration, stimulates efficient vectorial charge transfer between PCN and CoNiP and subsequent surface mass exchange. On the other hand, we also demonstrate that the well satisfied band structure of PCN can facilitate the two-electron reaction pathway. This work not only has implications for the potential use of CoNiP–PCN as potential photocatalyst for solar H 2 production, but also offers a new idea for pure water slitting in particulate system. Image 1 • Co x Ni y P-PCN has been synthesized by a unique two-step phosphating method. • Co x Ni y P-PCN is capable for pure water splitting into stoichiometric H 2 and H 2 O 2. • The proper band structure of PCN facilitates this two-electron transformation. • P severs as a unique chemical bridge for rapid and vectorial charge transfer. [ABSTRACT FROM AUTHOR]

Charge separation plays a crucial role in semiconductor-based photocatalytic CO 2 conversion. Herein, we developed a photo-magnetic coupling reactor to manipulate a unique induced electric field, which can control carrier behavior at the minuscule and boost the photocatalytic reduction of CO 2. A monolithic photocatalyst consisting of a copper foam substrate and nanosized ZnO/NiO/Au heterostructures was designed to couple the rotating magnetic field (RMF) in the reactor. Specifically, induced electric field is generated by copper foam cutting the magnetic induction line, which can increase the charge carrier density by preventing their recombination. Moreover, NiO and Au synergistically magnify the charge separation as the active sites for the oxidation and reduction reaction, respectively. The utilization rate of photogenerated electrons increases by 5.24 times after coupling RMF, with the yields of CO and CH 4 improved by 5.50 times and 5.18 times. This strategy of integrating the distinct RMF into the reaction provides new insights for improving photocatalytic CO 2 conversion. [Display omitted] • The monolithic photocatalyst made of a copper foam substrate and ZnO/NiO/Au. • Copper foam cuts magnetic induction line to generate the induced electric field. • Boosted photocatalytic CO 2 reduction by induced electromotive force. • Utilization rate of photogenerated electrons increases by 5.24 times with RMF. [ABSTRACT FROM AUTHOR]

Developing high‐efficiency yet low‐cost photocatalyst for solar hydrogen production by avoiding the use of noble metals has received adequate interest but remains a great challenge to date. This work reports a seed‐mediated hydrothermal approach for the synthesis of NiS2 quantum dots (QDs) anchored two‐dimensional graphitic carbon nitride (g‐C3N4) nanosheets. This hybrid shows superior performance toward photocatalytic H2 evolution from water. The highest H2 evolution rate reaches 4.841 μmol h−1, with an apparent quantum efficiency of 2 % at 425 nm, which is even much higher than that of Pt‐modified g‐C3N4 photocatalyst (2.865 μmol h−1). Moreover, the composite presents good stability without notable activity decay after several cycled tests. It is found that NiS2 QDs are essential for this improvement. These small nanoclusters not only benefit rapid and vectorial diffusion of photogenerated electrons from g‐C3N4 to NiS2, but also promote H2 evolution by decreasing the thermodynamic overpotential for proton reduction. This work thus marks an important step toward designing good‐performance and low‐cost photocatalytic materials for solar H2 conversion. Quantum on the dot: NiS2 quantum dot successfully anchored on the surface of g‐C3N4 promotes both vectorial charge diffusion and rapid proton reduction during photocatalytic water splitting. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Ultrathin TiO 2 shell was coated on chalcogenide nanorod as a protecting layer. • The synthesis relies on kinetic control for layer-by-layer deposition of TiO 2. • The heterostructure enables superior activity and stability of solar H 2 evolution. • Charge transfer is controlled by type-II band alignment and tunneling effect. Abstract It has been a subject of intensive research on avoiding photocorrosion of sulfide photocatalysts while retaining their activity for visible-light-driven photocatalysis. Herein, using Cd 0.9 Zn 0.1 S (CZS) nanorod as an example, we report an effective strategy based upon conformal coating of an ultrathin pinhole-free TiO 2 shell, with controllable thickness from 2 to 7 nm, on the nanorod as protecting layer. The synthesis relies on the use of a syringe pump for kinetic control, by which, TiO 2 can grow on the surface of CZS in a layer-by-layer mode. The core–shell heterostructures were found with excellent photocatalytic performance toward solar hydrogen production from a Na 2 S-Na 2 SO 3 aqueous solution. The reaction can stably proceed for 200 h without notable decay of the hydrogen evolution rate. A volcano-type relationship between the mass activity and the shell thickness was gained either in the presence of a cocatalyst or not. The heterostructure with a shell thickness of 2 nm presented the highest H 2 -evolution activity with a quantum efficiency of 19%. However, the one with a shell thickness of 7 nm, instead, was found to be more active, with a quantum efficiency reaching 44%, when 1 wt% NiS x cocatalyst was introduced. It is believed that photogenerated electrons transfer from CZS to TiO 2 , while the holes vanish via quantum-tunneling-induced recombination with the electrons. This work suggests that sulfide photocatalysts with desirable efficiency and corrosion resistance could be achieved by introducing conformal atomic TiO 2 layers. [ABSTRACT FROM AUTHOR]

Most photocatalytic reactions are conducted near room temperature. In this work, we explored photothermal hydrogen production in a carefully designed photo reactor with external heating. Light sources of different wavelength bands were investigated. Formic acid was used as sacrificial regent to study the photothermal hydrogen production activity. Interestingly, the photothermal reaction is not the simple sum of the photo and thermal effects but their synergetic coupling and at 90°C it is 8.1 and 4.2 times of that under photo or thermal conditions alone. With thermal excitation, the bound electrons in Pt can be excited which can easily overcome the energy barrier between Pt and lowest unoccupied molecular orbital of the adsorbed reactants. Activation of the substrate itself by light is also found to be crucial to trigger such photothermal reaction. It is therefore different from traditional plasma resonance induced photothermal reaction where long wavelength IR light is more preferred. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2916-2925, 2017 [ABSTRACT FROM AUTHOR]

We report efficient and simultaneous production of H 2 and H 2 O 2 from photocatalytic pure water splitting over a novel heterojunction photocatalyst made of red phosphorus (RP) and Co x P co-modified P-doped g-C 3 N 4 (PCN). The success relies on the formation of RP as an intermediate to link Co x P and PCN, introducing atomic-level homogeneous P-P/P-P bonds in the heterojunction. The crafted P-P/P-P bridges as unique channels enable controllable and smooth charge flow via strong electronic coupling between each component in the composite photocatalyst, endowing a boosted carrier kinetics. More significantly, RP also facilities a Z-scheme charge transfer that induces two-electron photocatalytic H 2 and H 2 O 2 production from pure water in 1:1 stoichiometry. The highest activity reaches 15.26 μmol h−1 for bifunctional chemical evolution under simulated solar light irradiation, with the apparent quantum efficiencies (AQE) of 6.2 % at 366 nm and 3.6 % at 425 nm, without using any noble metals on 50 mg of photocatalyst. The new insights of phosphorus bridges can be applied to other composite photocatalysts for reinforced reaction kinetics towards value-added chemicals generation. [Display omitted] • Red phosphorus (RP) and Co x P modified P-doped g-C 3 N 4 (PCN) is prepared. • The heterojunction enables efficient photocatalytic pure water splitting. • Water is split into stoichiometric H 2 and H 2 O 2 via a two-electron mechanism. • RP bridges Co x P and PCN leading to the formation of P-P/P-P homogeneous bond. • The P-P/P-P bond as unique channel facilitates rapid and smooth charge flow. [ABSTRACT FROM AUTHOR]

Abstract: A series of CdS and CdS/CNTs photocatalysts were successfully prepared by hydrothermal method and they were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), UV–visible optical absorption spectra (UV–Vis), etc. By studying their photocatalytic properties, it is found that, for CdS, photocatalysts prepared in appropriate alkaline environment presented higher hydrogen production activity, reaching 794.6 μmol h−1 g−1; the photocatalytic activity of CdS was obviously enhanced by combining it with CNTs via a special two-step hydrothermal method, and the corresponding hydrogen production rate reached 1.771 mmol h−1 g−1; the photocatalytic activity was further improved by loading co-catalyst NiS, achieving 12.13 mmol h−1 g−1. [Copyright &y& Elsevier]

The article discuses a research on determination of photo catalytic Hydrogen gas production activity using a multichannel system. It says that photo catalytic hydrogen is produced from water under visible range of light over a semiconductor. It mentions that newly designed catalysts are not exactly evaluated and tested due to lack of rapid screening technologies for photo catalytic activity analysis.

Abstract: Hydrogen production under visible light by photocatalytic reforming of glucose over an oxide solid solution photocatalyst BixY1−xVO4 (BYV) was demonstrated for the first time. It was found that a certain amount of Y doping would promote the transition of BiVO4 from monoclinic to tetragonal phase and finally lead to the formation of tetragonal BYV solid solution. BYV with a B/Y ratio of 1:1 showed the highest activity for hydrogen production. The amount of photoproduced hydrogen lowered after several hours of reaction. However, when the gas product was replaced with N2 atmosphere, hydrogen production recovered. It is supposed that the generated CO2 might participate in the redox reaction and in some way inhibit the hydrogen production. Therefore, for photocatalytic reforming of glucose, removal of gas product in time is indispensable. [ABSTRACT FROM AUTHOR]

Ni doped ZnInS microsphere with flower-like nanoscale petals were prepared by a hydrothermal method. There was an optimal Ni doping content of 0.3 wt% where hydrogen production reached the maximum. Higher Ni doping can hardly dope into the ZnInS lattice and just stay at ZnInS surface, leading to decreased activity. It was determined that Ni entering the ZnInS lattice instead of surface NiS dominated the enhanced photocatalytic activity. The experimental results were rationalized by assuming Ni serving as shallow trapping sites, greatly enhancing the activity of the photocatalyst. Graphical Abstract: Ni doped ZnInS microsphere with flower-like nanoscale petals were prepared by a hydrothermal method. There is an optimal Ni doping content of 0.3 wt% where hydrogen production reached the maximum. It is assumed that Ni serving as shallow trapping sites can separate the arrival time of e/h pairs at the petal surface of ZnInS, so as to greatly reduce their surface recombination and which, in turn, leads to improved hydrogen production.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: Decahedral Cu2WS4 was synthesized by a facile hydrothermal method and employed as photocatalyst for photocatalytic hydrogen production for the first time. The hydrothermal method avoids the traditional use of H2S for the preparation of such chalcogenide, which guarantees an environmental-friendly process. The properties of the Cu2WS4 samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–Vis reflectance spectra, etc. The results showed that the decahedral Cu2WS4 possessed a band gap of ca. 2.1ev. The photocatalyst was demonstrated to be very active under visible light for hydrogen production. Especially, Cu2WS4 synthesized at 200 °C for 72 h showed the highest activity with the apparent quantum yield of 11% at 425 nm. The correlation between the preparation parameters and the photocatalytic properties were investigated. It was expected this first report of W-based chalcogenide photocatalyst would add to the photocatalyst group and lead to the finding of new photocatalyst with much higher activity. [ABSTRACT FROM AUTHOR]

We report a photocatalytic system that utilizes Cd 0.5 Zn 0.5 S nanotwins decorated with various Ni-based co-catalysts for solar-driven hydrogen production through lignocellulose reformation. In this noble-metal-free system, Ni(OH) 2 emerges as the most effective Ni form in enhancing the photocatalytic evolution of H 2. By optimizing the composition with 3 wt% Ni(OH) 2 loading, we achieved the highest activity, with the hydrogen production rates of 7.00 mmol g−1 h−1 and 1.97 mmol g−1 h−1 from α-cellulose and waste straw photoreforming, respectively. This optimized composition exhibited the highest quantum efficiency of 7.68%. In principle, the lower potential of Ni2+/Ni compared to the conduction band of Cd 0.5 Zn 0.5 S facilitates the transfer of electrons from the conduction band of Cd 0.5 Zn 0.5 S to Ni(OH) 2. Specifically, during the photocatalytic reaction, a fraction of surface Ni(OH) 2 is reduced to Ni. The in-situ formed Ni clusters, along with the Ni(OH) 2 , enhance the separation photogenerated electrons and facilitate their transfer to H+, leading to significantly improved photocatalytic activity. This work not only provides an effective strategy for developing more efficient photocatalysts, but also offers a direct means of harnessing clean energy from abundant waste biomass on Earth. • Ni(OH) 2 /Ni atoms or clusters can serve as co-catalysts enhance the hydrogen production activity of Cd 0.5 Zn 0.5 S. • The cellulose/lignocellulose photoreforming system exhibits exceptional H 2 production efficiency. • The photothermal effect of the Ni(OH) 2 /Cd 0.5 Zn 0.5 S photocatalyst enhances the reaction activity. [ABSTRACT FROM AUTHOR]

Multifaceted Cu2O with controlled crystal facet exposure was synthesized via a facile one-step method. It was found that photogenerated electrons prefer to accumulate on high index planes, while holes tend to migrate to {100} facets of a Cu2O polyhedron, leading to efficient charge separation and enhanced photocatalytic reforming of glucose. [ABSTRACT FROM AUTHOR]

We report the synthesis of a Z-scheme monolithic photocatalyst in the form of copper foam (CF) supported TiO 2 combining Cu 2 O and Ag nanoparticles (CF@TiO 2 /Cu 2 O-Ag). The designed catalysts with efficient charge separation show superior photocatalytic activity toward CO 2 reduction, with a maximum CO yielding rate of 25.58 μmol‧g-1‧h-1. More importantly, we develop a solar-wind energy complementary device, which enables the strong coupling of the magnetic field into the photocatalytic reaction. Specifically, the in-situ space electric field generated from the wind-driven induced electromotive force further enhances the separation and transportation of photogenerated charge carriers in the Z-scheme system. The productivity of CO in the proof-of-concept device based on the use of CF@TiO 2 /Cu 2 O-Ag catalyst reaches 71.66 μmol‧g-1‧h-1. This study provides an ideal approach for reinforcing photocatalytic CO 2 reduction through muti-field coupling and highlights the prospect of solar-wind energy coupled photocatalysis. [Display omitted] • Preparation of monolithic Z-scheme CF@TiO 2 /0.6Cu 2 O-0.6Ag photocatalyst. • Z-scheme heterostructure enables effective carrier transportation and separation. • Loading of Cu 2 O and Ag promotes photoreduction of CO 2 into CO. • Construction of environmental friendliness solar-wind photocatalytic reactor. • Induced electromotive force raised from magnetic field boosts charge separation. [ABSTRACT FROM AUTHOR]

Shape-controlled synthesis of semiconductor nanocrystals enables fine manipulation over their physicochemical properties. In this paper, unique Cd 0.9 Zn 0.1 S tetrapod nanostructures consisting of two different polymorphisms, i.e. , wurtzite and zinc blende, were successfully synthesized via a simple ethylenediamine-assisted solvothermal route. It is found that the temperature determines the formation of the zinc blende-structured seeds, while the ethylenediamine facilitates the subsequent preferential growth of the wurtzite phase arms. Furthermore, the tetrapods, characterized by a type-II staggered band alignment, have shown enhanced photocatalytic performance for H 2 generation from an aqueous solution containing electron donors under visible light irradiation, in comparison to the nanocrystals with distinct morphologies. Our results indicate that coupling different polymorphisms in a nanocrystal may be advantageous for photocatalytic proton reduction over single-crystal photocatalyst. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Heterojunction design in a two‐dimensional (2D) fashion has been deemed beneficial for improving the photocatalytic activity of g‐C3N4 because of the promoted interfacial charge transfer, yet still facing challenges. Herein, we construct a novel 2D/2D Cu3P nanosheet/P‐doped g‐C3N4 (PCN) nanosheet heterojunction photocatalyst (PCN/Cu3P) through a simple in‐situ phosphorization treatment of 2D/2D CuS/g‐C3N4 composite for photocatalytic H2 evolution. We demonstrate that the 2D lamellar structure of both CuS and g‐C3N4 could be well reserved in the phosphorization process, while CuS and g‐C3N4 in‐situ transformed into Cu3P and PCN, respectively, leading to the formation of PCN/Cu3P tight 2D/2D heterojunction. Owing to the large contact area provided by intimate face‐to‐face 2D/2D structure, the PCN/Cu3P photocatalyst exhibits significantly enhanced charge separation efficiency, thus achieving a boosted visible‐light‐driven photocatalytic behavior. The highest rate for H2 evolution reaches 5.12 μmol·h–1, nearly 24 times and 368 times higher than that of pristine PCN and g‐C3N4, respectively. This work represents an excellent example in elaborately constructing g‐C3N4‐based 2D/2D heterostructure and could be extended to other photocatalyst/co‐catalyst system. [ABSTRACT FROM AUTHOR]

Abstract: Na2Ti2O4(OH)2 nanotubes were obtained by hydrothermal reaction of TiO2 with concentrated NaOH solution. CdS nanoparticles were then decorated on Na2Ti2O4(OH)2 nanotubes through partial ion-exchange method. The composite photocatalysts were characterized by X-ray diffraction (XRD), ultraviolet–visible spectra (UV–vis), transmission electron microscope (TEM), etc. The results showed that CdS nanoparticles of 5–6nm were anchored on the surface of the Na2Ti2O4(OH)2 nanotubes. Under irradiation of visible light (λ ≥430nm), the prepared CdS/Na2Ti2O4(OH)2 showed high photoactivity for hydrogen production. [Copyright &y& Elsevier]

Abstract: Ni2+ doped Cd1−x Zn x S microsphere photocatalysts were prepared by a new hydrothermal method. Experimental results showed that the doped Ni2+ can not only affect the crystal structure and morphology of Cd1−x Zn x S photocatalysts, but also greatly improve its photocatalytic activity. It was found that 0.1wt% Ni2+ doped Cd0.1Zn0.9S photocatalyst showed the highest activity with the apparent quantum yield of 15.9% at 420nm. The reason for the positive effects of Ni2+ was discussed. [Copyright &y& Elsevier]

Graphical abstract Highlights • A hollow NiS/CdS/TiO 2 photocatalyst was prepared by a hydrolysis process. • Photocatalytic activity of TiO 2 was improved by anchoring CdS and NiS. • The synergistic effect of the heterojunction and cocatalyst promote H 2 production. Abstract Noble-metal-free hollow NiS/CdS/TiO 2 (NS/CT) nanohybrid photocatalyst was prepared by a facile hydrolysis combining sulfidation process using metal–organic framework (MOF) as a template. The as-prepared composites were characterized by SEM, TEM, XRD, XPS, UV–vis, and photoelectrochemical techniques. It is found that NS/CT composites with porous hollow structure show significantly enhanced photocatalytic efficiency compare to TiO 2 , or CdS/TiO 2 , or even Pt decorated CdS/TiO 2 photocatalysts, for hydrogen evolution from water upon visible light irradiation. Significantly, NS/CT composite with optimum amount of 30% CdS and 0.3% NiS exhibits the highest photoactivity, with H 2 production rate of 2149.15 µmol·g−1·h−1, which is 23.9 and 2.3 times higher than that of the pure CdS particles and the CdS/TiO 2 nanocomposites, respectively. The superiority of the composites arises from the synergistic effect of the heterojunction for rapid charge separation and the NiS cocatalyst for accelerated surface redox reaction. [ABSTRACT FROM AUTHOR]

Porous Cr 2 O 3 /g-C 3 N 4 composites were prepared by a facile one-pot pyrolysis method and showed enhanced visible-light-driven photocatalytic H 2 -evolution activities, with the highest rate 4.0 times of that for pure g-C 3 N 4 . During the one-pot process, accompanied by the pyrolysis of melamine to form g-C 3 N 4 , CrCl 3 ·6H 2 O acted as Cr precursor to form Cr 2 O 3 , and meanwhile functioned as pore-forming agent to increase the surface area and pore volume of g-C 3 N 4 . The cocatalytic effect of Cr 2 O 3 and the favorable textural properties of g-C 3 N 4 promoted the separation of photogenerated charge carriers, facilitated the diffusion, accumulation and adsorption of reactants, enriched the reactive sites for redox reaction, and thus resulted in the enhanced photocatalytic activities. This work presented an effective route to simultaneously optimize the compositions and micro/nano-structures of photocatalysts for H 2 evolution. [ABSTRACT FROM AUTHOR]

Gas adsorption/desorption process and conversion efficiency of solar energy are crucial to photocatalytic CO 2 conversion. Here, we report the synthesis of a metal-organic-framework based monolithic NF@ZnO/Au@ZIF-8 photocatalyst that can simulate the respiratory process to accelerate adsorption of CO 2 and desorption of CH 4 during the photocatalytic reaction. Particularly, this selective-breathing monolithic photocatalyst could coupling external magnetic field into the photocatalytic process, achieving photo-thermal-magnetic field synergy in the reaction system. Upon this photo-thermal-magnetic coupling, the temperature of surface reaction could be elevated to about 180 °C, leading to a drastically improved charge transfer behavior and the significantly increased breathing efficiency. The yield of CH 4 over the selective-breathing monolithic NF@ZnO/Au@ZIF-8 photocatalyst reaches 270.02 μmol/g with a high stability and a high selectivity up to 89.72%. This study provides an ideal approach for the design of monolithic catalysts not only with balanced gas adsorption-desorption property, but also endowed with multi-field coupling ability. [Display omitted] • Monolithic NF@ZnO/Au@ZIF-8 photocatalysts successfully synthesized. • Effects of respiration centers Au content and ZIF-8 thickness on catalyst activity. • The effect of CO 2 adsorption by ZIF-8 layer was investigated. • The selective-breathing effect of photocatalyst was proposed. • The yield and selectivity of CH 4 boosted by photo-thermal-magnetic coupling. [ABSTRACT FROM AUTHOR]

We report a facile, one-pot synthesis of spherical Cu/Cu 2 O yolk-shell nanocrystals (Cu/Cu 2 O YSNSs) with tunable morphologies and explored their applications for assisting photocatalytic hydrogen evolution. The success of current synthesis relies on the reduction of Cu(NO 3) 2 by ascorbic acid in the presence of octadecyl trimethylammonium chloride (OTAC) and hexamethylenetetramine (HMTA). It is found that the variation of OTAC concentration would lead to the formation of Cu/Cu 2 O YSNSs with tunable morphologies. The as-prepared Cu/Cu 2 O YSNSs are further anchored by TiO 2 nanoparticles (Degussa P25) to construct Cu/Cu 2 O/TiO 2 nanocomposites for applications in photocatalytic H 2 evolution under simulated sunlight irritation. The resulting metal-semiconductor nanostructures have remarkable photocatalytic activity in H 2 evolution from water-methanol mixtures, with the product rate being almost 97 times greater than that of the pure P25 catalysts. Such improvement should be attributed to the unique hollow structure and the presence of multi-valent copperish species. The current study describes a feasible one-pot strategy to synthesize copperish oxide nanocrystals with tunable yolk-shell morphologies and validates their promising use in as co-catalyst for photocatalytic hydrogen evolution to illustrate the advantage from both the structure and composition. Yolk-shell Cu/Cu 2 O nanospheres with tunable morphologies are prepared in high purity via a one-pot method. By anchoring with TiO 2 nanoparticles (P25), they exhibit excellent photocatalytic activity (~97 times greater than P25 in hydrogen production rate) and long-term durability towards photocatalytic hydrogen evolution, illustrating the structural and morphological advantages. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Photo-thermal-magnetic three-field coupling for enhanced CO 2 photo-reduction. • Nickel foam was used as nickel source and catalyst support. • 0.01 wt% Cu/Cu 2 O/HNF exhibited the best catalytic activity and CH 4 selectivity. • The heat of the reaction system came from magnetic-thermal and photo-thermal effects. Aiming at the bottleneck of thermodynamics, kinetics and reaction systems in photothermal catalytic CO 2 reduction conversion, a three-field coupling method based on the efficient utilization of solar energy and the application of a photo-thermal-magnetic three-field was proposed to achieve efficient and highly selective CO 2 conversion. The composite monolithic catalyst with three field response functions and multiple active reaction interfaces was prepared by using photoactive copper supported by nickel foam. The effect of an external alternating magnetic field on photocatalytic CO 2 reduction was studied using a range between 0.005 and 0.1 wt% Cu/Cu 2 O/Ni(OH) 2 /NF as catalysts. The results showed that 0.01 wt% Cu/Cu 2 O/Ni(OH) 2 /NF exhibited the best catalytic activity and CH 4 selectivity under alternating magnetic field enhanced photocatalysis. The main products were CO (6.76 μmol g−1) and CH 4 (167 μmol g−1). The selectivity of CH 4 was 96.1%. The yields of CH 4 using this method were 11 and 6 times higher than the yields obtained with photocatalysis (14.58 μmol g−1) and magnetic-thermal catalysis (26.75 μmol g−1), respectively. According to the analysis of temperature measurements and electrochemical measurements, the surface temperature of the three-field coupled catalyst reaches about 230 °C. Applying an alternating magnetic field can effectively reduce the recombination of photogenerated electron holes. Alternating magnetic field enhanced photocatalytic CO 2 reduction conversion provides a new and promising method for the efficient conversion and utilization of solar energy. [ABSTRACT FROM AUTHOR]

The successful phosphorization of gallium indium zinc oxynitride consists of GaInZnON core and InP shell with an ideal type-II band alignment. With efficient charge separation during photocatalytic pure water splitting, the AQE can be up to 10.6% at 430 nm and 13.8% at 350 nm, respectively. • A core-shell GaInZnON@InP heterojunction photocatalyst is prepared. • The heterojunction displays an ideal type-Ⅱ band alignment. • The band alignment enables efficient charge separation. • Photocatalytic overall water splitting with an AQY of 10.6% is achieved. Overall water splitting via solar-driven photocatalysis provides an ideal way to realizing a viable and sustainable hydrogen economy, while the development of efficient photocatalysts remains a grand challenge to date. Herein, we report the successful surface phosphorization of a gallium indium zinc oxynitride (GaInZnON) photocatalyst, which comprises a GaInZnON core and a thin InP shell. The success to the synthesis relies on the rapid diffusion of In from the bulk to the crystal surface and preferential combination of In with P to form an outer layer. The enhanced charge migration was confirmed with characterization and the charge redistribution difference around the heterojunction. The core-shell composite having an ideal type-II band alignment enables efficient charge separation within the particle scale and significantly improved photocatalytic activity toward pure water splitting for simultaneous and stoichiometric H 2 and O 2 evolution. The apparent quantum efficiencies can be up to 10.6% at 430 nm and 13.8% at 350 nm, respectively. Our results suggest that such core-shell GaInZnON@InP architectures hold great potential for efficient and scalable solar hydrogen generation. [ABSTRACT FROM AUTHOR]

• CuO QDs are encapsulated in MIL-125(Ti) via a complexation-oxidation method. • Ternary g-C 3 N 4 /CuO@MIL-125(Ti) enables efficient photocatalytic CO 2 reduction. • CuO QDs are crucial in altering the reaction pathway for the production C2+. • The composite photocatalyst shows good stability and recyclability. Improving the stability of metallic oxide quantum dots (QDs) in a reaction system containing water is crucial for their practical applications in photocatalytic reduction of carbon dioxide. Herein, we use simple complexation-oxidation method to encapsulate CuO QDs in the pores of metal organic framework of MIL-125(Ti), and further combine it with g-C 3 N 4 to form a composite photocatalyst, i.e. , g-C 3 N 4 /CuO@MIL-125(Ti). Benefiting from the protection of the framework of MIL-125(Ti), the composite photocatalyst exhibits significantly improved stability in reaction systems containing water. In addition, due to the close contact of CuO QDs to the active catalytic site of Ti in MIL-125(Ti), the photogenerated electrons in the MIL-125(Ti) and g-C 3 N 4 can be smoothly transferred to the confined CuO QDs, which remarkably enhances the photocatalytic activity of g-C 3 N 4 /CuO@MIL-125(Ti) for photocatalytic CO 2 reduction in the presence of water. An optimization of the photocatalyst has led to the yields of CO, methanol, acetaldehyde and ethanol up to 180.1, 997.2, 531.5 and 1505.7 μmol/g, respectively. This work provides an effective strategy for improving the stability and charge separation property of metallic oxide-QDs modified photocatalyst toward efficient photocatalytic CO 2 reduction. [ABSTRACT FROM AUTHOR]

• Solvothermal processed melem is crucial for tailoring carbon nitride structure. • Nitrogen defects and few-layer nanosheet are simultaneously formed in carbon nitride. • DCNS-120 has optimal properties by combining nitrogen defect and nanosheet structure. • DCNS-120 shows 33-folds increase compared to BCN for photocatalytic H 2 production. Carbon nitride nanosheets have shown a great promise for photocatalytic water splitting among numerous photocatalysts due to the versatile advantages. The crucial issues of the weak visible-light absorption and the separation of photo-generated carrier remain a matter of serious concern. Herein, we report a facile calcination-solvothermal-calcination method to prepare nitrogen-deficient carbon nitride nanosheets (DCNS) for the first time, which leads to the simultaneous introduction of nitrogen defects and formation of a fragmented few-layer nanosheet structure. The fragmented few-layer nanosheet structure is known to possess a high specific surface area and abundant interfacial reaction sites, contributing to the rapid consumption of photo-generated carrier. The nitrogen defects are responsible for further boosting the photocatalytic performance by regulating the band structure and optical properties as well as improving the separation efficiency of photo-generated carrier. The optimized DCNS-120 delivers a superior H 2 production rate of 5375 μmol·g−1·h−1, considerably higher than that of bulk carbon nitride (164 μmol·g−1·h−1). We anticipate that this work may pave a new pathway to engineering carbon nitride with a matched structure to achieve the desired efficient photocatalytic H 2 production under visible-light irradiation. [ABSTRACT FROM AUTHOR]

• Pd nanocubes integrate on the surface of STO nanocubes at [100] orientation. • Lattice-oriented contact at the interface contributes to fluent charge transfer. • An appropriate Schottky barrier is achieved over smaller Pd nanocubes. • Integration of smaller Pd nanocubes gives better photocatalytic activity. Semiconductor-metal hybrids have been extensively studied for solar-to-hydrogen conversion. Delicate control on surface of cocatalysts and primary photocatalysts and interface therein can remarkably improve the photocatalytic efficiency. Herein, taking size-controlled Pd nanocubes and SrTiO 3 (STO) nanocubes as models, the integration of Pd nanocubes on STO nanocubes (Pd/STO) surface was achieved via an in-situ growth method. The composite photocatalyst presents significant enhancement toward photocatalytic hydrogen production compared to the similar counterpart prepared by simple mechanical self-assembly of Pd and STO, as well as to the pristine STO. The highest hydrogen evolution rate reaches 0.44 mmol h−1 g−1. The success relies on the lattice-oriented growth of Pd nanocubes on STO nanocubes for rapid charge separation from STO to Pd, and accelerated energy and mass exchange on surface of Pd. We believed that the strategy can provide a general guidance to develop more surface and interface-modified metal-semiconductor hybrid systems for hydrogen production. [ABSTRACT FROM AUTHOR]

• A core-shell p -type GIZON homojunction photocatalyst is prepared. • The homojunction shows an ideal type-I band alignment. • An intermediate band nearby the Fermi level of the shell promotes charge transfer. • Photocatalytic overall water splitting with an AQY of 3.5% is achieved. Direct overall water splitting via photocatalysis provides a potential pathway for solar energy conversion. The essential section is to develop efficient and stable photocatalysts, yet with limited success to date. Here a novel p -type gallium indium zinc oxynitride homojunction photocatalyst with core-shell structure is reported, which exhibits H 2 and O 2 evolution rates of 603 and 274 μmol h−1 g−1 with an apparent quantum efficiency of 3.5% at 430 nm from overall pure water splitting. Precise characterizations and DFT calculations reveal that the excellent photocatalytic performance is ascribed to the facilitated charge transfer contributed by the ideal type-I band alignment between GaInZnON core and GaInON shell, combined with the intermediate level formed nearby the Fermi level of GaInON shell. Our work offers insight into the development of facile synthesis of core-shell structure photocatalysts towards efficient solar-driven overall water splitting. [ABSTRACT FROM AUTHOR]