Design and fabrication of hollow structured Cu2MoS4/ZnIn2S4 nanocubes with significant enhanced photocatalytic hydrogen evolution performance

The unique architecture is very significant for photocatalysts to achieve high photocatalytic efficiency. Herein, hollow Cu₂MoS₄/ZnIn₂S₄ heterostructural nanocubes with intimate-contact interface have been prepared for the first time via a self-template way, which can promote the photocatalysis hydrogen evolution. First, novel hollow structured Cu₂MoS₄ nanocubes were successfully synthesized using Cu₂O as a precursor, then the ZnIn₂S₄ nanosheets were in-situ grew on the surface of hollow Cu₂MoS₄ nanocubes. The unique hollow heterostructures have markedly enhanced photocatalytic efficiency, and 15 wt% Cu₂MoS₄/ZnIn₂S₄ sample exhibits the highest hydrogen production rate of 8103 μmol·h⁻¹·g⁻¹, which is approximately four times higher than pure ZnIn₂S₄. The improved photocatalytic performance is mainly attributed to the following two points: (1) the hollow nanocube structure can provide rich active sites and increase light absorption; (2) forming a built-in electric field is conducive to transfer the holes generated by ZnIn₂S₄ to Cu₂MoS₄, which can effectively promote charge separation. This work may provide insights for the design of hollow architecture cage materials for high photocatalytic performance.     

Hierarchical ZnIn2S4: A promising cocatalyst to boost visible-light-driven photocatalytic hydrogen evolution of In(OH)3

Efficient separation of electrons and holes, associated with the reduction and oxidation, is of great importance in a photocatalytic reaction. 3D hierarchical core-shell-like ZnIn₂S₄@In(OH)₃ microspheres have been fabricated by a facile hydrothermal method via controlling the sulfur source. The marigold-like spherical ZnIn₂S₄ induced the in situ growth of cubic In(OH)₃ nanosheets as the outer shell, which efficiently transferred the photogenerated electrons and achieved efficient charge separation efficiency for highly photocatalytic H₂ production. Moreover, the intimate interfacial contact between ZnIn₂S₄ core and In(OH)₃ shell offered rectified charge transfer directions, which further boosted the charge separation. In consequence, the photocatalytic H₂ evolution under visible light irradiation was achieved on wide-gap In(OH)₃ owing to ZnIn₂S₄ as a cocatalyst, and a prominent photocatalytic H₂ production of 2088 μmol g⁻¹ was obtained on core-shell-like ZnIn₂S₄@In(OH)₃ structure with an apparent quantum efficiency of 1.45% (400 nm), which was nearly 2-folds higher of H₂ production rate than the pristine ZnIn₂S₄. This work provides a prototype material for high efficiency of hydrogen evolution, and gives a new insight for the development of efficient heterojunction photocatalysts.     

ZnIn2S4 modified CaTiO3 nanocubes with enhanced photocatalytic hydrogen performance

Novel ZnIn₂S₄/CaTiO₃ nanocubes were prepared by a two-step method and used as a visible light photocatalyst for efficient hydrogen production. The control of the content of CaTiO₃ could effectively change the photocatalytic H₂ production activity of ZnIn₂S₄/CaTiO₃ nanocubes, and the maximum H₂ evolution amount reached to 133116.43 μmol g⁻¹ in 6 h. The photocatalytic hydrogen production efficiency of ZnIn₂S₄/CaTiO₃ nanocubes was almost 4.5 times higher than that of pure ZnIn₂S₄. The electrochemical impedance spectrum of ZnIn₂S₄/CaTiO₃ exhibited the smallest arc radius, time-resolved PL spectrum showed that the carrier lifetime of ZnIn₂S₄/CaTiO₃ nanocubes was 3.29 ns, and the photocurrent density of ZnIn₂S₄/CaTiO₃ reached to 0.81 μA cm⁻². The prepared ZnIn₂S₄/CaTiO₃ nanocubes increased visible light absorption, improved the separation and transfer of photo-generated electrons and holes, and inhibited the recombination of photo-generated electron-hole pairs. ZnIn₂S₄/CaTiO₃ nanocubes exhibited the enhanced photocatalytic activity and high stability, and could be used as promising photocatalyst for hydrogen production application.     

Direct Z-scheme ZnIn2S4/LaNiO3 nanohybrid with enhanced photocatalytic performance for H2 evolution

The direct Z-scheme ZnIn₂S₄/LaNiO₃ nanohybrid based on ZnIn₂S₄ nanosheets and LaNiO₃ cubes was synthesized by a facile hydrothermal method. The ZnIn₂S₄/LaNiO₃ nanohybrid showed improved photocatalytic H₂ evolution and stability. The photocatalytic H₂ evolution activity of ZnIn₂S₄/LaNiO₃ nanohybrid is 3-fold enhanced than that of bare ZnIn₂S₄. The enhanced performance of ZnIn₂S₄/LaNiO₃ nanohybrid is mainly ascribed to the formation of heterojunction between LaNiO₃ and ZnIn₂S₄. The heterojunction can facilitate charge transport on the interface between LaNiO₃ and ZnIn₂S₄ and suppress the recombination of photo-generated charge carriers over ZnIn₂S₄/LaNiO₃ nanohybrid, which were well demonstrated by photoelectrochemical tests. Moreover, the direct Z-scheme photocatalytic reaction mechanism was proposed to elucidate the improved performance of ZnIn₂S₄/LaNiO₃ nanohybrid photocatalyst. This study may provide some guidance on the construction of direct Z-scheme photocatalytic system for photocatalytic H₂ evolution.     

TiO2 hollow spheres with separated Au and RuO2 co-catalysts for efficient photocatalytic water splitting

Hollow mesoporous TiO₂ photocatalysts with dual co-catalysts, located at specific positions, were prepared using Polystyrene (PS) as sacrificial templates. Au nanoparticles (NPs) were in situ loaded on the surface of PS spheres and the resulting nanocomposites were coated with TiO₂ shell using sol-gel reaction. The outer surface of core-shell spheres was impregnated with Ru and the subsequent calcination produced hollow anatase spheres with Au and RuO₂ dual co-catalysts. The hollow mesoporous spheres of Au@TiO₂@RuO₂ were proved by various techniques such as TEM, EDX, and SEM images. Photocatalysts were applied for hydrogen generation from water splitting and that with dual co-catalysts showed efficient catalytic activity under simulated solar light. The catalytic activity of photocatalysts with both oxidation and reduction co-catalysts (Au@TiO₂@RuO₂) showed hydrogen evolution (3165 μmol g⁻¹) almost two times more than that Au@TiO₂ and TiO₂@RuO₂ with single co-catalysts. And the hydrogen evolved is more than three times as compared to TiO₂ (935 μmol g⁻¹) without any co-catalyst. Hollow mesoporous morphology with different co-catalysts on inner and outer surfaces is believed to enhance photocatalytic activity which is due to better separation of photo-generated charges.     

Construction of 3D/3D heterojunction between new noble metal free ZnIn2S4 and non-inert metal NiMoO4 for enhanced hydrogen evolution performance under visible light

Promoting the separation of electron and hole plays an important role in photocatalytic hydrogen production. However, single semiconductor materials cannot fully realize their potential due to the rapid recombination of photogenerated carriers. Therefore, in this experiment, a new photocatalyst ZnIn₂S₄/NiMoO₄ was prepared by using an electrostatic self-assembly method, which greatly improved the electron-hole recombination phenomenon. After 5 h reaction under visible light irradiation, ZIS/NMO-3 composite catalyst prepared in ethanol showed the best photocatalytic activity, and the hydrogen evolution capacity reached 173.09 μmol. The hydrogen evolution capacity of ZIS/NMO-3 was 2.47 and 25.83 times that of short rod-like NiMoO₄ and microflower-like spherical ZnIn₂S₄, respectively. Through some physical characterization and electrochemical experiments, it can be seen that NiMoO₄ and ZnIn₂S₄ have good composability. Meanwhile, the composite catalyst ZnIn₂S₄/NiMoO₄-3 has high current response characteristics. It can be seen from the fluorescence emission spectra that the composite catalyst presents the lowest peak value, which indicates that ZIS/NMO-3 can effectively inhibit the recombination of photogenerated electrons and holes. When ZnIn₂S₄ is loaded on NiMoO₄, the separation of photogenerated carrier will be accelerated due to the formation of heterojunction, thus improving the photocatalytic activity. At the same time, the large specific surface area will also provide more abundant active sites for the composite catalyst, which provides a good condition for photocatalytic hydrogen production. This work provides an efficient, uncomplicated and feasible method for the synthesis of ZIS/NMO-3 composite catalyst with excellent properties.     

Polyoxo-titanium clusters dually functionalized ZnIn2S4/MIL-101 catalyst for photocatalysis of aquatic hydrogen production

Herein, we have extended a reasonable strategy to design and prepare a series of photocatalysts ZIS/MIL-101/PTCs (ZIS = ZnIn₂S₄, MIL = Materials of Institute Lavoisier, PTCs = Polyoxo-titanium clusters) with evidently enhanced photocatalytic activity for H₂ evolution. The synthesis of all photocatalysts was carried out by traditional step-by-step in situ reaction method without special treatment. As expected, the photocatalytic H₂ production rates by the three PTCs hybrid catalysts (ZIS/MIL-101/PTCs), namely ZIS/MIL-101/PTC-3, ZIS/MIL-101/PTC-7 and ZIS/MIL-101/PTC-9, were approximately 4, 7 and 12 times higher than that of ZIS/MIL-101, respectively. The results of UV–Vis diffuse reflectance spectroscopy and photoelectric responses show the reasons for boosting photocatalytic activity are that introduction of PTCs can well match energy gap and accelerate the photogenerated charge carriers transfer. This dual functionalization of PTCs can also be further confirmed by the photocatalytic activities of three La-ZIS/MIL-101/PTCs (La-ZIS/MIL-101/PTC-3, La-ZIS/MIL-101/PTC-7 and La-ZIS/MIL-101/PTC-9) photocatalysts doped with the La element.     

The ZnIn2S4/CdS hollow core-shell nanoheterostructure towards enhanced visible light photocatalytic H2 evolution via bimetallic synergism

The ZnIn₂S₄/CdS hollow core-shell nanoheterostructure with bimetallic synergism is synthesized via a hybrid chemical method. As revealed, the ZnIn₂S₄/CdS hollow core-shell nanoheterostructure (ZnIn₂S₄/CdS-3) exhibits remarkable visible light photocatalytic hydrogen evolution (～5209.43 μmol·g^?1·h^?1, AQE of ～20.26%) than that of single CdS (～40 folds) and single ZnIn₂S₄ (～12 folds), and achieves decent photocatalytic stability (average HER performance of ～5056.80 μmol·g^?1·h^?1), which is mainly ascribed to that, the formed ZnIn₂S₄/CdS heterostructure with appropriate potential gradient and Zn/In bimetallic synergism can improve carrier transportation, including increasing carrier transportation, prolonging lifetime and decreasing recombination, the hollow core-shell nanostructure can provide abundant active sites and increase solar efficiency, while can maintain a photocatalytic stability.     

Photocatalytic hydrogen evolution and antibiotic degradation by S-scheme ZnCo2S4/TiO2

In this study, ZnCo₂S₄ (ZCS) nanoparticles were coupled on the surface of TiO₂ by simple solvothermal method to form S-scheme heterojunction. Compared with ZCS and TiO₂, the photocatalytic performance of ZCS/TiO₂ under simulated sunlight is significantly improved, and its hydrogen evolution efficiency reaches 5580 μmol·g^?1·h^?1 with the apparent quantum efficiency (AQY) up to 11.5% at 420 nm, which is 88.3 times and 54.3 times that of TiO₂ and ZCS, respectively. Moreover, ZCS/TiO₂ also has excellent performance in the photocatalytic degradation of tetracycline (TC). The enhancement of photocatalytic performance of ZCS/TiO₂ is mainly due to S-scheme heterojunction. On the one hand, the S-scheme electron transfer path not only improves the electron-hole separation efficiency, but also improves the charge transfer efficiency. On the other hand, ZCS significantly enhances the visible light absorption of ZCS/TiO₂. The photocatalytic mechanism and S-scheme heterojunction structure is confirmed by XPS, EPR, ultraviolet photoelectron spectroscopy (UPS) and energy band structure. This work provides a new idea for designing and constructing S-scheme heterojunction to improve the performance of photocatalytic hydrogen evolution and TC degradation.     

Enhanced photocatalytic hydrogen evolution over 0D/3D NiTiO3 nanoparticles/CdIn2S4 microspheres heterostructure photocatalyst

Constructing S-scheme heterojunction is regarded as an effective mode to motivate excellent photocatalytic performance for hydrogen generation. This paper prepares NiTiO₃/CdIn₂S₄ S-scheme heterostructure photocatalyst by hydrothermal method successfully. In the experiments, 20 wt% NiTiO₃/CdIn₂S₄ has the supreme photocatalytic activity with the H₂ generation rate of 5168.6 μmol g⁻¹ h⁻¹ and the apparent quantum yield (AQY) of 5.14% at 420 nm, approximately 7.7 times of pure CdIn₂S₄. Through the phase characterization analyses, NiTiO₃ and CdIn₂S₄ successfully compounded, with NiTiO₃ nanoparticles wrapping around CdIn₂S₄ microspheres to form the irregular clumps. Further analyses of performance reveal the larger specific surface area, wider absorption region, faster charge transfer rate, outstanding photostability and recyclability for 20 wt% NiTiO₃/CdIn₂S₄, all of which play the significant role in photocatalytic hydrogen evolution activity. Finally, a plausible S-scheme photocatalytic mechanism for NiTiO₃/CdIn₂S₄ is proposed. This study provides a novel and effective S-scheme photocatalyst for hydrogen generation from water splitting.     

Promoted charge separation on 3D interconnected Ti3C2/MoS2/CdS composite for enhanced photocatalytic H2 production

The construction of heterojunction has been regarded as an effective way to promote photocatalytic H₂ evolution activity, in which an intimately interfacial contact between the materials forming heterojunction is a positive effect on enhancing activity. Herein, a ternary 3D interconnected nanocomposite Ti₃C₂/MoS₂/CdS was synthesized by a hydrothermal method. MoS₂ nanosheet with a vertically aligned structure grew on the surface of multi-layered Ti₃C₂ to form 3D Ti₃C₂/MoS₂ with tightly interfacial contact, which works as a cocatalyst for enhancing photocatalytic H₂ evolution. CdS as a photocatalyst covered the surface of Ti₃C₂/MoS₂ to absorb light energy. Benefitting to the synergistic effect between Ti₃C₂ and MoS₂, the Ti₃C₂/MoS₂ further accelerates electron transfer and inhibits the recombination of carriers. The H₂ evolution rate of Ti₃C₂/MoS₂/CdS reaches 15.2 mmol h^?1 g^?1 and the apparent quantum yield is 42.1% at λ = 420 nm. The result provides a useful insight for developing cocatalysts with new nanostructures via controlled interfacial engineering.     

A thin clothe coated architecture of ZnIn2S4/H2Ta2O6 for enhanced photocatalytic hydrogen production

Focused on energy and environment issues, in present investigation, an economical and eco-friendly photocatalyst for hydrogen evolution in water splitting reaction has been designed and fabricated. The characteristics by XRD, TEM, XPS and AFM confirmed that an octahedral H₂Ta₂O₆ is uniformly capsuled by ZnIn₂S₄ thin clothes to form a package ZnIn₂S₄/H₂Ta₂O₆ heterojunction. The assembled ZnIn₂S₄/H₂Ta₂O₆ exhibits superior hydrogen generated performance with a value of 3217.31 μmol g⁻¹•h⁻¹ under simulated sunlight irradiation, without obvious deactivation in five consecutive cycles. The enhanced activity and reusability are mainly attributed to ultrathin clothe-like shell, the well-matched band structure and a large tight contact interface in the package type construction, which can promote redox ability, extend light harvesting range and boost charge separation efficiency. The present study proposes a new design idea to assemble a highly efficient and durable photocatalyst for solar hydrogen generation by splitting water.     

Fabrication of CuO/MoO3 p-n heterojunction for enhanced dyes degradation and hydrogen production from water splitting

The development of excellent photocatalytic material is highly required for energy and environmental applications. In this study, visible light responsive p-n heterojunction photocatalysts based on CuO/MoO₃ with varying ratios of CuO were prepared by the facile hydrothermal method. The crystalline structure, surface morphology, chemical compositions and optical properties of the synthesized photocatalysts were studied using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), photoluminescence (PL) techniques and UV–Vi's absorption spectroscopy. The results showed that the 5%CuO/MoO₃ nanocomposite displayed enhanced photocatalytic performance for the production of hydrogen (98.5 μmol h^?1g^?1) and degradation of dyes rhodamine B (RhB) and alizarine yellow (AY) than all other samples. Furthermore, 5% CuO/MoO₃ composite exhibited excellent stability after five consecutive cycles for both RhB and AY dyes. Overall, the improved photocatalytic performance of 5%CuO/MoO₃ composite was due to increased adsorption of visible light, good surface morphology, enhanced charge separation/transfer which inhibited recombination of electrons and holes. This study could encourage the synthesis of novel and effective p-n heterojunction photocatalysts for practical applications.     

Novel synthesis of graphene oxide/In2S3/TiO2 NRs heterojunction photoanode for enhanced photoelectrochemical (PEC) performance

Novel heterostructure photocatalyst built from titanium dioxide (TiO₂), graphene oxide (GO) and indium sulfide (In₂S₃) has been successfully prepared for photoelectrochemical hydrogen production. The stepwise introduction of three materials on conductive glass substrate has been realized through hydrothermal, electrochimical and spin coating deposition methods, respectively. The structure, morphology, composition, optical and photoelectrochemical properties of the resultant photoanodes were investigated in detail. The presence of GO in the heterostructure film was confirmed by Raman analysis with D and G band intensity. Surface morphology analysis of the GO/In₂S₃/TiO₂ NRs structure reveal the homogenous distribution of graphene oxide on In₂S₃/TiO₂ NRs surface. From UV–Vis analysis, band gap energy of the samples decreases gradually from 3.34 eV (TiO₂ NRs) to 3.12 eV, with In₂S₃ and GO addition. The electrochemical impedance spectroscopy (EIS) further confirmed that GO/In₂S₃/TiO₂NRs heterostructure possessed the lowest charge-transfer resistance, revealing that In₂S₃ and GO could significantly accelerate the electron mobility compared with bare TiO₂. From Mott-Schottky plots, several parameters such as flat-band potential and free carrier concentration were determined. Next, The GO/In₂S₃/TiO₂ NRs electrode achieved remarkably improved current density (0.45 mAcm² at 0.8 V vs Ag/AgCl) compared to pure TiO₂ NRs or In₂S₃/TiO₂ NRs electrodes, which attributes to the uniform structure and excellent electrical conductivity of GO, which could reduce the combination rate of the photo electron-hole pairs. These results reveal that GO/In₂S₃/TiO₂ NRs possesses great potential toward the development of newly synthesizable catalysts in the field of photoelectrochemical water splitting.     

Properly aligned band structures in B-TiO2/MIL53(Fe)/g-C3N4 ternary nanocomposite can drastically improve its photocatalytic activity for H2 evolution: Investigations based on the experimental results

The development of new tools that could meet the demand of sustainable energy production has attracted worldwide scientific attention. Over the past few decades, significant research efforts have been carried out to efficiently reduce water to H₂ (green fuel) over semiconductor photocatalysts. Numerous semiconductor photocatalysts have been employed in photocatalysis for optimum H₂ production. All the techniques were chosen based on their flexibility, cost-effectiveness, and ease of availability. Recently, polymeric carbon nitride (g-C₃N₄) received worldwide attention in visible light photocatalysis for energy and environmental applications due to its low price, robust nature, and superior thermal stability. Nevertheless, g-C₃N₄ (CN) exhibits shortfalls such as high charge carrier's recombination rate and weak reduction ability. To overcome these drawbacks, herein, for the first time we have fabricated B-TiO₂/MIL-53(Fe)/CN ternary composite via hydrothermal and wet-chemical methods. The resultant B-TiO₂/MIL53(Fe)/CN ternary composite shows drastically improved photocatalytic activity for hydrogen evolution compared to the bare CN, B-TiO_2, and MIL53(Fe) components. The B-TiO₂/MIL53(Fe)/CN ternary composite produced approximately 166.3 and 581.2 μmol h^?1 g^?1 of hydrogen under visible light and UV–visible light irradiations, respectively, with the assistance of co-catalyst Pt. Photo-luminescence (PL) and the fluorescence (FL) spectroscopy measurements reveal that the enhanced photoactivity is due to the greatly promoted charge carrier's separation and transfer at the interfacial contact of the well-aligned three-component systems. This work will promote the design and development of efficient photocatalyst based on CN for clean energy production and environmental purification.     

CdS/CuCo2S4 dots-on-rods boosting charge separation and hydrogen evolution

Herein, we report a new class of CdS/CuCo₂S₄ dots-on-rods nanostructures that exhibit efficient visible-light-induced H₂ evolution from water. The material CuCo₂S₄ nanodots over CdS nanorods are fabricated through controlled loading in a facile hydrothermal process and formed a heterojunction, maximizing the energy conversion, that shows advanced performance in photochemical H₂ evolution (rate: 33.32 mmol g^?1h^?1 and AQY: 13.2% at λ = 420 ± 15 nm) from water. The experimental and theoretical results on physical and chemical properties revealed that the photocatalytic system is positively correlated with the H₂ production rate and suggest that CuCo₂S₄ nanodots in CdS nanorods plays a critical role in relative efficiency of the H₂ generation. The surprisingly high activity was attributed to enhanced charge carriers’ separation and transfer efficiency, confirmed by the kinetic measurements (TAS) and further reinforced from the Kelvin probe force microscopy (KPFM) analysis and theoretical understanding.     

Interstitial carbon doped of setaria viridis-like Znln2S4 hollow tubes for efficient the performance of photocatalytic hydrogen production

In the photocatalytic water splitting hydrogen production system, the key to efficient use of solar energy is to choose a suitable photocatalyst. As an important ternary sulfide, ZnIn₂S₄ (ZIS) has attracted wide attention because of its narrow band gap (E_g = 2.3–2.8 eV) and wide light absorption range. However, further modification was still needed. Therefore, in this work, the unique C/ZIS hollow tubes with nano-flakes were prepared by a simple solvothermal method. To a large extent, this unique structure increased the utilization of light and active sites. Moreover, the dissolution of PAN during the solvothermal process caused the carbon element to be uniformly doped into the hollow tube framework. After a series of characterization results, C/ZIS-3.0 has the best hydrogen release rate (1241.94 μmol g⁻¹ h⁻¹) and good cyclability under visible light irradiation (λ ≥ 420 nm). And its unique morphology and possible catalytic mechanism were further discussed.     

Composite of g-C3N4 and poly(3-hexylthiophene) prepared by polymerizing thiophene-3-acetic acid treated g-C3N4 and 3-hexylthiophene for enhanced photocatalytic hydrogen production

Composite of g-C₃N₄ and poly(3-hexylthiophene) (P3HT) with enhanced photocatalytic H₂ production activity was prepared by polymerizing 3-hexylthiophene and g-C₃N₄, which was treated with thiophene-3-acetic acid (T3A). The morphology, chemical structure, and light absorption properties of samples were characterized by SEM, TEM, BET, XRD, FT-IR, XPS, UV–visible diffuse reflectance spectra (UV–vis). The migration and separation efficiency of charge carriers were characterized by photoluminescence (PL) emission spectra, Time resolved photoluminescence spectra, transient photocurrent responses, and electrochemical impedance spectroscopy (EIS). The photocatalytic activity of the catalysts were tested as the H₂ evolution rate from water under visible light irradiation in the presence of triethanolamine as sacrifice agent. The results indicated that g-C₃N₄-P3HT composite shows significant enhanced migration and separation efficiency of charge carriers, and photocatalytic H₂ production activity from water. The intrinsic nature causing the significance enhanced photocatalytic performance was discussed. Our findings here may provide a new strategy to design composite photocatalyst with high photocatalytic activity.     

Hollow In2O3 nanotubes decorated with Cd0.67Mo0.33Se QDs for enhanced photocatalytic hydrogen production performance

Novel Cd_0.67Mo_0.33Se/In₂O₃ hollow nanotubes were prepared for photocatalytic hydrogen production application. Under visible light irradiation, Cd_0.67Mo_0.33Se/In₂O₃ hollow nanotubes showed enhanced photocatalytic performance. And the apparent quantum efficiency of 34.86% was obtained when irradiated with 420 nm monochromatic light. The modification of Cd_0.67Mo_0.33Se QDs on the surface of In₂O₃ hollow nanotubes effectively improved the utilization rate of light absorption, increased the separation and migration rate of electrons, inhibited the recombination of photo-generated electron and hole pairs, thus enhancing the photocatalytic activity of water splitting to produce hydrogen. It would be an efficient photocatalyst for hydrogen production application in future.     

Cd0.5Zn0.5S/Ni2P noble-metal-free photocatalyst for high-efficient photocatalytic hydrogen production: Ni2P boosting separation of photocarriers

Establishing efficient co-catalytic loaded semiconductors for efficient charge separation is a hopeful way for enhance photocatalytic water splitting hydrogen evolution. Herein, we successfully constructed the Cd_0.5Zn_0.5S/Ni₂P (CZS/Ni₂P) nanocomposites via two-step hydrothermal method. The CZS/Ni₂P composites show much improved activity than the origin CZS for photocatalytic H₂ generation. When the content of Ni₂P loaded on the Cd_0.5Zn_0.5S (CZS) is 0.3 mol%, the photocatalyst achieves the highest photocatalytic hydrogen generation rate of 41.26 mmol g⁻¹ h⁻¹ under visible light. The Ni–S bonds on the close contact interface between CZS and Ni₂P can be act as electron-bridge to provide a channel for electron transfer. During the photocatalysis processing, Ni₂P can be used as electron traps to attract electrons from CZS, resulting in the improvement of the photocatalytic performance.