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The directional synthesis of transition metal phosphides was considered to be an effective strategy to solve the overdependence of noble metals on photocatalytic hydrogen evolution (PHE) reactions. Inspiringly, this work reported a facile method for constructing hollow Co 2 P nanocages (Co 2 P NCGs) that derived from ZIF-67 by calcining and phosphiding procedure in nitrogen atmosphere to act as non-noble metal cocatalysts. Followed with further coating thin-layered ZnIn 2 S 4 (ZIS) on the surface of Co 2 P NCGs through a hydrothermal reaction, the hierarchical robust Co 2 P/ZnIn 2 S 4 nanocages (Co 2 P/ZIS NCGs) were then delicately fabricated as efficient photocatalysts for PHE reactions. The uniquely hollow structure of Co 2 P NCGs largely diffused the photogenerated chargers that induced from ZIS and the closely interfacial contact significantly promoted the separation and transfer of electrons from ZIS to Co 2 P according to density functional theory (DFT) calculation, synergistically resulting in an efficient hydrogen generation performance. PHE results showed that an efficient H 2 evolution rate of 7.93 mmol/g/h over 10% Co 2 P/ZIS NCGs was achieved, about 10 times higher than that of pristine ZnIn 2 S 4. More importantly, the hierarchically hollow Co 2 P/ZIS NCGs exhibited ascendant PHE activity in comparison with that of 1% noble metal (Pt, Au, Ag) loaded ZnIn 2 S 4 with superior sustainability, all indicating the efficient and stable photocatalysts of Co 2 P/ZIS NCGs for PHE reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow tubular ZnIn 2 S 4 modified with embedded metal-organic-framework-layers (ZnIn 2 S 4 -MOFL) were rationally designed. • Efficient ZnIn 2 S 4 -MOFL released H 2 bubble at the optimum rate of 28.2 mmol/g/h. • The Z-scheme photocatalytic system strongly promoted the separation of electron and hole pairs. • DFT results revealed the decreased density of states of ZnIn 2 S 4 after coupling with the organic ligands of MOFL. This work reported a facile one-step method for constructing hollow tubular ZnIn 2 S 4 modified by metal-organic-framework-layers (MOFL) with In-MOF as precursor to be efficient photocatalysts (ZnIn 2 S 4 -MOFL) for robust photocatalytic hydrogen evolution (PHE). The dominant catalyst of ZnIn 2 S 4 and cocatalytic role of MOFL synergistically promoted the separation of electron and hole pairs due to the direct Z-scheme photocatalytic system, leading to an extraordinarily high PHE activity. The density functional theory (DFT) results revealed the remarkably decreased density of states (DOS) of ZnIn 2 S 4 after coupling with the organic ligands of MOFL, indeed proving an effectively suppressed recombination of charge carriers and benefited the performance of photocatalytic reactions. Experimental PHE results showed that a large number of hydrogen bubbles were visible to naked eyes and the optimal hydrogen evolution reached 28.2 mmol/g/h, the highest value reported so far among ZnIn 2 S 4 -based photocatalysts, and almost 14.8 times higher than that of pristine ZnIn 2 S 4. More importantly, the superior apparent quantum efficiencies (AQEs) of 22.67 % at monochromatic light (350 nm) and the stable hydrogen generation capability (5.7 mmol/g/h) under real sunlight irradiation all confirmed a promising catalyst of ZnIn 2 S 4 -MOFL for hydrogen evolution applications. [ABSTRACT FROM AUTHOR]