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The robust photocatalytic hydrogen evolution (PHE) from water needs an effective photogenerated charge spatial separation and enough contact between reactant and catalyst, but the synthesis of catalysts with the characteristics remains a challenge. Herein, we report the design of core-shell heterostructure consisted of thin TiO2 layer uniformly coated on porous ZrO2 polyhedron for effective PHE. In this system, UiO-66-NH2, one of popular MOF with Zr as metal node, has been chosen as the precursor template due to its plentiful pores, uniform morphology, as well as the rich NH2 groups. Our results show that Ti precursor can uniformly coat on UiO-66-NH2, by means of interaction of tetrabutyl titanate (TBT) with -NH3 in UiO-66-NH2. Followed by the calcination, the Ti precursor and UiO-66-NH2 can be converted into ZrO2 and TiO2, respectively, thus leading to the formation of ZrO2@TiO2 core-shell heterostructure. The ZrO2@TiO2-500 has the high specific surface area of 52.4 m2 g−1. Besides, the intimate contact of TiO2 shell with ZrO2 core facilitates the separation and migration of photoinduced carriers, exposing more active sites for the surface photocatalytic hydrogen evolution reaction. The spectrum and electrochemical characterization further exhibit the extended life of photon-generated carrier and easy mass transfer. The optimized ZrO2@TiO2-500 shows enhanced photocatalytic rate of 39.7 mmol h−1 g−1, much higher than those of ZrO2 (0.8 mmol h−1 g−1) and TiO2 (7.6 mmol h−1 g−1).

Cu2O is widely used in the visible-light photocatalytic field, but its photocatalytic activity and stability still need to be further enhanced. Thus, searching for an efficient method to inhibit photocorrosion of Cu2O and boost its photogenerated charge carriers’ separation is very important and challenging. Herein, Cu2O@CuS core-shell hexapetalous flowers were synthesized by hydrothermal and in-situ chemical vapor deposition (CVD) strategy. The Cu2O hexapetalous flowers were firstly obtained through hydrothermal procedure, and then CuS in-situ grew on Cu2O to form core-shell structure by CVD, which effectively inhibited the photocorrosion of Cu2O. Meanwhile, Cu2O@CuS core-shell structure could extend their light absorption ranges from 200 to 1500 nm; promote the separation of electrons and holes in photocatalytic system. Thus, under the wide-spectral region, Cu2O@CuS exhibited excellent photocatalytic performance for the degradation of tetracycline at 91% with good cycling ability, resulting from the effective separation of photogenerated charges, more free radicals such as OH and O2−, increases of utilization rate of visible-light. These results indicate that in-situ CVD strategy is a feasible method to improve visible-light photocatalytic activity and stability of Cu2O.

The robust photocatalytic hydrogen evolution (PHE) from water needs an effective photogenerated charge spatial separation and enough contact between reactant and catalyst, but the synthesis of catalysts with the characteristics remains a challenge. Herein, we report the design of core-shell heterostructure consisted of thin TiO