Facile construction of a robust CuS@NaNbO nanorod composite: A unique p-n heterojunction structure with superior performance in photocatalytic hydrogen evolution.

The construction of heterojunctions is commonly regarded as an efficient way to promote the production of hydrogen via photocatalytic water splitting through the enhancement of interfacial interactions. The p-n heterojunction is an important kind of heterojunction with an inner electric field based on the different properties of semiconductors. In this work, we reported the synthesis of a novel CuS/NaNbO p-n heterojunction by depositing CuS nanoparticles on the external surface of NaNbO nanorods, using a facile calcination and hydrothermal method. Through the screening of different ratios, the optimum hydrogen production activity reached 1603 μmol·g·h, which is much higher than that of NaNbO (3.6 times) and CuS (2.7 times). Subsequent characterizations proved semiconductor properties and the existence of p-n heterojunction interactions between the two materials, which inhibited the recombination of photogenerated carriers and improved the efficiency of electron transfer. This work provides a meaningful strategy to utilize the p-n heterojunction structure for the promotion of photocatalytic hydrogen production.