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[Display omitted] • A ternary heterostructure (ZnPPO) is constructed for photocatalytic H 2 evolution. • ZnPPO presents an enhanced photocatalytic H 2 evolution rate of 31.037 mmol h-1g−1. • A binding structure of Ⅱ-type and Z-scheme has been constructed in ZnPPO. • The binding structure promotes the transfer of photogenerated charge carriers. A ternary heterostructure (ZnPPO) was constructed by loading ZnO and tetrakis (4-carboxyphenyl) zinc porphyrin (ZnTCPP) with P-doped g-C 3 N 4 (PCN). In contrast to binary heterostructures (PCN-ZnO, ZnTCPP-ZnO and ZnTCPP-PCN) and single components (PCN, ZnTCPP and ZnO), ZnPPO has superior photocatalytic activity for H 2 generation from water splitting. It is revealed that a binding structure of Ⅱ-type and Z-scheme has been constructed in ZnPPO, which plays a vital role in transferring photo-excited charge carriers. The significant enhancement of photocatalytic activity in ZnPPO is attributed to the effective transfer of photo-generated electrons and holes between the components of the ternary heterostructure. [ABSTRACT FROM AUTHOR]

[Display omitted] • CdS@ZnO core–shell NRAs is constructed by ALD for H 2 evolution from PEC water splitting. • CdS@ZnO 200 presents an enhanced PEC H 2 evolution rate of 21.64 μmol·h−1·cm−2. • Z-scheme mechanism between CdS and ZnO promotes the separation of electrons and holes. • The close contact between two semiconductors reduces transfer resistance of charge carriers. • ZnO shell tightly wraps CdS core to prevent its photo-corrosion. Photoelectrochemical (PEC) water splitting provides a promising strategy for the production of clean hydrogen fuel. Herein, a new CdS@ZnO core–shell nanorod arrays (NRAs) is successfully constructed by atomic layer deposition (ALD) for H 2 evolution from PEC water splitting. The CdS@ZnO 200 obtained after 200 ALD cycles presents a significantly enhanced PEC H 2 evolution rate of 21.64 μmol·h−1·cm−2, which is about 9.4 times of pristine CdS NRAs (2.31 μmol·h−1·cm−2). The reasons for the improved PEC H 2 evolution performance can be ascribed to several aspects: firstly, the Z-scheme charge transfer mechanism formed between CdS core and ZnO shell promotes the effective spatial separation of photo-induced electrons and holes; secondly, the close contact between the two semiconductors resulted from ALD process helps to reduce the transfer resistance of charge carriers. In addition, the CdS core is tightly wrapped by ZnO shell, which helps to prevent the photo-corrosion of CdS core. This work provides a new type of photoanode material suitable for PEC H 2 evolution from water splitting, and provides an efficient anti-corrosion method for the use of photocorrosive semiconductor materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • g-C 3 N 4 /Ni/CdS is constructed by insetting highly dispersed Ni atoms between g-C 3 N 4 and CdS. • The resultant g-C 3 N 4 /Ni/CdS displays a high H 2 evolution rate of 9.5 mmol/g/h. • Ni atoms dispersed on the surface of g-C 3 N 4 contribute to the intimate deposition of CdS. • Ni atoms facilitate the rapid transfer of charge carriers between g-C 3 N 4 and CdS. Highly efficient interface charge carrier transfer and separation is a primary factor in guaranteeing the performance of hetero photocatalysts. Here, we construct a high-performance g-C 3 N 4 /CdS heterostructure by insetting highly dispersed Ni atoms between g-C 3 N 4 nanosheets and CdS nanoparticles, and the obtained CNN/Ni 500 /CdS-2.4 displays the highest H 2 evolution rate of 9.5 mmol/g/h without the addition of extra co-catalyst, which is about 4.3 times to that of CNN/CdS heterostructure without Ni atom addition. It is found that the significantly enhanced H 2 evolution ability can be ascribed to the dual function of Ni atoms in linking hetero interfaces and facilitating charge transport. The introduced Ni atoms disperse uniformly on the surface of g-C 3 N 4 and thus contributing to the large area uniform and intimately deposition of CdS nanoparticles, which provides sufficient surface-active sites for the photocatalytic reaction. At the same time, due to the good the conductivity, the introduction of Ni atoms dramatically facilitates the rapid transfer of charge carriers between g-C 3 N 4 and CdS and thus accelerating the generation of hydrogen. This work demonstrates the great potential of trace amount of highly dispersed metals on improving the quality of heterojunctions and promoting the photocatalytic ability of heterostructures. [ABSTRACT FROM AUTHOR]