Introducing phosphorus and sulfur into nickel-zeolite imidazolium framework-based carbon to form junction for enhanced photocatalytic H2 generation

Abstract

Herein, a novel paradigm of carbon-based heterojunctions, including Ni2P/N-doped carbon (Ni2P-NC) and NiS2/N-doped carbon (NiS2-NC), are successfully prepared by using nickel-based zeolite imidazolium framework (Ni-ZIF) material as precursor via a one-step calcination method to introduce phosphorus and sulfur atoms in the carbonization process. Owing to the formation of Ni2P and NiS2 in these heterojunctions, the separation and transfer of photogenerated charge carriers are significantly enhanced, thus greatly improving the H2 yield ability, up to 6.74 mmol/g of Ni2P-NC and 2.02 mmol/g of NiS2-NC, which are about 3.96 and 1.2 times higher than that of the Ni-NC, respectively. Under the action of eosin-Y photosensitizer, the apparent quantum efficiency of Ni2P-NC at 365 nm is 41.4%. Furthermore, the H2 production mechanism in the Ni2P-NC/Eosin Y/TEOA system has been discussed in details. This work could inspire the design and construction of MOF-derived high-performance hydrogen evolution photocatalysts.