One-pot construction of CoSe nanoparticles anchored on single-atomic-Co doped carbon for pH-universal hydrogen evolution

Revealing the underlining interactions between different active sites is of great significance to the rational design of highly efficient non-noble-metal composites for the hydrogen evolution reaction. Herein, we report a pre-chelation assisted one-pot synthesis of a heterostructure CoSe/Co-N-C, where uniform CoSe nanoparticles are supported and enwrapped by single atomic Co doped carbon backbones. CoSe/Co-N-C demonstrates superior HER activities in the entire pH range, requiring small overpotentials of 71 mV, 63 mV, and 128 mV to drive a current density of 10 mA cm(-2) in 1.0 M KOH, 0.5 M H2SO4, and 1.0 M PBS, respectively. Moreover, remarkable long-time stabilities are achieved in all electrolytes, thanks to the attenuated corrosion with the carbon layer encapsulation derived from the fluid catalytic cracking slurry. To elucidate the interaction mechanism, theoretical calculations reveal an apparent electron transfer at CoSe and Co-N-C interfaces, which modulates the electronic structures to realize the improved intrinsic HER activities. The synergistic advances of excellent activity and remarkable stability in a wide range of pHs present its great potential for practical hydrogen mass production.