Single-Atom Pd–N_(3)Sites on Carbon-Defi cient g-C_(3)N_(4)for Photocatalytic H_(2)Evolution

摘要

Photocatalytic hydrogen evolution is an attractive fi eld for future environment-friendly energy.However,fast recombination of photogenerated charges severely inhibits hydrogen effi ciency.Single-atom cocatalysts such as Pt have emerged as an eff ective method to enhance the photocatalytic activity by introduction of active sites and boosting charge separation with low-coordination environment.Herein,we demonstrated a new strategy to develop a highly active Pd single atom in carbondefi cient g-C_(3)N_(4)with a unique coordination.The single-atom Pd–N_(3)sites constructed by oil bath heating and photoreduction process were confi rmed by HADDF-STEM and XPS measurements.Introduction of single-atom Pd greatly improved the separation and transportation of charge carriers,leading to a longer lifespan for consequent reactions.The obtained singleatom Pd loaded on the carbon-defi cient g-C_(3)N_(4)showed excellent photocatalytic activity in hydrogen production with about 24 and 4 times higher activity than that of g-C_(3)N_(4)and nano-sized Pd on the same support,respectively.This work provides a new insight on the design of single-atom catalyst.