In Situ Synthesis of Few‐Layered g‐C3N4 with Vertically Aligned MoS2 Loading for Boosting Solar‐to‐Hydrogen Generation

Abstract In artificial photocatalytic hydrogen evolution, effective incident photon absorption and a high‐charge recombination rate are crucial factors influencing the overall efficiency. Herein, a traditional solid‐state synthesis is used to obtain, for the first time, novel samples of few‐layered g‐C 3 N 4 with vertically aligned MoS 2 loading (MoS 2 /C 3 N 4 ). Thiourea and layered MoO 3 are chosen as precursors, as they react under nitrogen atmosphere to in situ produce the products. According to the quasi‐Fourier transform infrared reflectance and X‐ray diffraction measurements, the detailed reaction process is determined to proceed through the confirmed formation pathway. The two precursor units MoS 2 and C 3 N 4 are linked by MoN bonds, which act as electronic receivers/conductors and hydrogen‐generation sites. Density functional theory is also carried out, which determines that the interface sites act as electron‐accumulation regions. According to the photoelectrochemical results, MoS 2 /C 3 N 4 can achieve a current of 0.05 mA cm −2 , which is almost ten times higher than that of bare g‐C 3 N 4 or the MoS 2 /C 3 N 4 ‐R reference samples. The findings in the present work pave the way to not only synthesize a series of designated samples but also thoroughly understand the solid‐state reaction.