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Due to the poor photocatalytic hydrogen evolution ability of pure CdS, we need to develop a photocatalytic hydrogen evolution catalyst with high activity and no precious metal doping. Therefore, in this article, we used a simple hydrothermal synthesis of CdS nanoparticles, using water as a carrier, loading a small amount of amorphous CoS, by changing the loading ratio of amorphous CoS, synthesized TYPE–II type heterojunction composite catalyst CCS. The successful synthesis of the composite catalyst CCS was verified by XRD, SEM and other characterization methods. UV–vis, PL and other characterization showed that the supported amorphous CoS could significantly improve the photocatalytic activity of CdS, and the photochemical detection also showed that the performance of composite catalyst CCS was better than that of pure CdS. Using Na2S and Na2SO3 mixed solution as electron sacrificial agent, the hydrogen production performance of CCS composite catalyst was determined through hydrogen evolution experiment and cyclic stability experiment. It was found that the sacrificial agent had a great promotion effect on the hydrogen production performance of photocatalyst. It was found that the hydrogen production rate of the composite catalyst could reach 2.01 mmol·g−1·h−1, which was 6.3 times of the pure CdS. This study offers a novel approach for the design of amorphous–based nanostructures as efficient hydrogen evolution cocatalysts. First, CdS are excited by light, consuming S2− and SO32− ions in the sacrificial agent, generating a large number of electrons and holes. Due to the energy difference between the conducting band (CB) of CdS and amorphous CoS, the electrons are transferred from the surface of CdS to the conducting band (CB) of amorphous CoS, while the electrons obtained from water and H+ in the sacrificial agent are reduced to H2. The amorphous CoS is used as the transfer medium of electron acceptor, and the synergistic effect between heterojunctions is used to improve the charge separation efficiency and electron transfer rate. Therefore, the photocatalytic hydrogen production effect of the composite catalyst CCS–7 has been greatly improved. [ABSTRACT FROM AUTHOR]

The highly selective production of reduced multicarbon products with long‐term durability for CO2 electroreduction reaction (CO2RR) using clean and renewable electricity is currently a major challenge. Copper nanoparticles (Cu NPs) are exceptionally advantageous for CO2RR to yield multielectron transfer chemical products such as ethylene and ethanol. However, Cu NPs for CO2RR generally require high overpotential to produce multiple electron transfer C2+ products with poor stability. Herein, an imidazolium‐functionalized covalent triazine framework (ICTF) stabilized Cu NPs (Cu/ICTF) for the enhanced CO2RR to produce ethylene is reported. The imidazolium groups in the cationic ICTF not only can enhance CO2 capture capacity and lower the energetic barrier to activate CO2, but also the in situ formed N‐heterocyclic carbenes (NHC) could stabilize Cu NPs to prevent their deactivation. Thus, the Cu/ICTF demonstrated higher selectivity (35 %) for the electroreduction of CO2 to ethylene with larger partial current density of ethylene (4.14 mA cm−2) over the unmodified neutral CTF stabilized Cu NPs (Cu/CTF) with 29 % Faradaic efficiency (FE) of ethylene and current density of 3.69 mA cm−2. Moreover, the active sites could be stabilized by the in situ produced NHC in ICTF and the current density and C2H4 FE of Cu/ICTF50 were almost maintained after 10 h continuous electrolysis experiment, while the C2H4 FE of Cu/CTF50 were lost ca. 42 % of its original value after 7 h. This strategy provides a facile approach to stabilize active sites for CO2RR and may bring new inspiration to apply in energy storage and conversion. [ABSTRACT FROM AUTHOR]

In this paper, the new composite material Co–Mo–S/Ni(OH)2 has high hydrogen evolution ability under photoreaction, the hydrogen evolution of Co–Mo–S/Ni(OH)2 composite material reaches 357 μmol after reaction 3 h, and the catalyst still exhibits high photocatalytic activity after four cycles under light response. It shows that this new catalyst has high activity and stability. The results of XPS, TEM, SEM and XRD indicate that the composite catalyst is successfully synthesized. The results of PL and electrochemical experiments show that Ni(OH)2 attached to Co–Mo–S can increase the transfer of photogenerated electrons and reduce the recombination of electrons and holes. From the UV–visible and BET characterization, the presence of Ni(OH)2 increases the range of response of the Co–Mo–S to sunlight, the pore volume and surface range, which improves the absorption capacity of the catalyst for ErB. Therefore, Co–Mo–S/Ni(OH)2 has excellent application prospect. [ABSTRACT FROM AUTHOR]

Sm2MoO6/Ni(OH)2 was successfully immersed in water first, and the sensitizer is Eosin Y and the sacrificial agent is triethanolamine agent for high-efficiency photocatalytic production of H2. When Sm2MoO6 was loaded onto the surface of Ni(OH)2, the photocatalytic activity (2407.48 μmol g−1 h−1) was 2.6 times that of Ni(OH)2 (925.36 μmol g−1 h−1), which was Sm2MoO6 (169.36 μmol g−1 h−1) is 14.2 times. From a series of characterizations, Sm2MoO6 is an effective cocatalyst to improve the separation of photo-generated charges and the efficiency of electron transfer. Large specific surface areas are a primary requirement for high efficiency catalysts, and the catalyst is sufficiently into contact with the sensitizer and the sacrificial agent to soar the photocatalytic activity. The first condition for an excellent catalyst is that it has a large specific surface area and can provide more active sites. In the dye sensitization system, the photocatalytic activity of Sm2MoO6/Ni(OH)2 is 2.6 times that of Ni(OH)2 and 14.2 times that of Sm2MoO6. Sm2MoO6 is an effective co-catalyst. [ABSTRACT FROM AUTHOR]

In this study, a CoS/NiMoO4 composite catalyst with good TYPE-II heterojunction was prepared by hydrothermal method with NiMoO4 nanorods, with water as a medium to load small amount of amorphous CoS, by changing the loading amounts of amorphous CoS. X-ray diffraction, UV–Visible diffuse reflection and other characteristics indicate that doped amorphous CoS can significantly improve the photocatalytic performance of NiMoO4, and the charge separation and electron transfer efficiency of composite catalysts detected by photoelectric chemistry are also significantly improved compared with NiMoO4. The photocatalytic activity and stability of the composite catalyst were studied by hydrogen evolution experiment. The hydrogen production rate of the composite catalyst can reach 338 μmol, which is 3.23 times higher than pure NiMoO4. This simple hydrothermal synthesis of photocatalytic materials provides new ideas and methods for the design and development of new composite photocatalysts. [ABSTRACT FROM AUTHOR]

The CoNi 2 S 4 /CdWO 4 -3 (CNS/CW-3) was an excellent photocatalyst for hydrogen evolution. The controlled morphology of CNS/CW-3 was successfully by adding thiourea as sulfur source and TBA to control the CoNi 2 S 4 nanoparticles. The photocatalytic hydrogen evolution activity of CoNi 2 S 4 and CdWO 4 under visible light irradiation was studied with different CoNi 2 S 4 incorporation ratios. UV–vis absorption spectra showed that the absorbance of CNS/CW-3 composite catalyst increased significantly after doping CoNi 2 S 4. The electrochemical and photoelectrochemical experiments also showed that the charge separation and electron transfer efficiency were higher when CoNi 2 S 4 was attached to CdWO 4. CNS/CW-3 exhibited excellent photocatalytic activity for hydrogen evolution under visible light irradiation. Its hydrogen evolution activity reached 269.08 μmol in 5 h, and had good light stability. It was a potential strategy to design photocatalyst with controllable morphology. The new composite material CoNi 2 S 4 /CdWO 4 has good photocatalytic activity and stability under visible light irradiation. UV–vis analysis showed that the band gap of the composite photocatalyst increased after hydrothermal recombination. In addition, under the regulation of TBA, CoNi 2 S 4 /CdWO 4 has a large specific surface area and pore volume, which is conducive to EY adsorption and electron transfer. The composite photocatalyst CoNi 2 S 4 /CdWO 4 with controllable flower globule has good application potential. Unlabelled Image • As a new kide of photocatalyst, it had a unique internal structure and good synergy, which greatly enhanced the photocatalytic activity of CuCo 2 S 4. • The electron transfer and charge separation were significantly improved by the uniform diffusion of CdWO 4 rod on the spherical CoNi 2 S 4 surface. • Bimetallic sulfides had a large specific surface area and provided more active sites to promote photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

Photocatalytic material Zn x Cd 1-x S band gap adjustment avoids composite Z-scheme heterostructure construction. • Efficient photocatalytic H 2 evolution material NiCo 2 S 4 @Zn 0.5 Cd 0.5 S was prepared. • Zn x Cd 1-x S energy band adjustment induced the conversion of photo-generated carrier transmission path. • Direct Z-scheme heterojunction between NiCo 2 S 4 and Zn 0.5 Cd 0.5 S was constructed. The hollow sphere structure of NiCo 2 S 4 achieved uniform contact between composite material. Based on hollow spherical NiCo 2 S 4 , Zn x Cd 1-x S with adjustable band structure was used to construct a composite for photocatalytic hydrogen evolution. The hollow spherical structure of NiCo 2 S 4 gives Zn x Cd 1-x S more contact positions to form a stable heterojunction. Through the band structure adjustment for Zn x Cd 1-x S, the induced electron transfer model was transformed into Z-scheme, which effectively enhances the photo-produced carrier separation efficiency of the composite material. At the same time, the fast electron transfer is realized by the great conductivity of the hollow spherical NiCo 2 S 4. This allows the composite material to obtain a shorter average lifetime of PL (0.15 ns) compared to Zn 0.5 Cd 0.5 S (3.9 ns). The composite NiCo 2 S 4 @Zn 0.5 Cd 0.5 S with Z-scheme heterojunction exhibited excellent photocatalytic HER activity and stability due to its unique spatial structure and efficient Z-scheme electron transfer path. The optimized composite NiCo 2 S 4 @Zn 0.5 Cd 0.5 S 1:1 photocatalytic HER rate reached 233.68 μmol.h−1, which is equivalent to 5.81 times that of Zn 0.5 Cd 0.5 S (40.25 μmol.h−1). [ABSTRACT FROM AUTHOR]