Effects of hydrophobic layer on selective electrochemical nitrogen fixation of self-supporting nanoporous Mo4P3 catalyst under ambient conditions

Electrochemical nitrogen reduction reaction (ENRR) of N-2 to NH3 under ambient condition offers an environmentally-friendly and sustainable development approach that is expected to replace energy-intensive Haber-Bosch process. However, the ENRR process is suppressed with competition from unavoidable hydrogen evolution reaction (HER). Herein, we modify d-band structure of self-supporting nanoporous Mo4P3 (np-Mo4P3) catalyst by preparing fluorosilane (FAS) hydrophobic layer on the ligament surface. This approach weakens the absorbability of H and simultaneously prevent water close to active site, further suppress HER. Besides, the self-supporting nanoporous structure provides rich active sites for ENRR. The hydrophobic np-Mo 4 P 3 exhibits good ENRR performance, such as high FE of 10.1 % and superior NH3 yield of 17.3 mu g cm(-2). The hydrophobization method offers an attractive strategy for suppressing HER and could be extended across metal catalyst for ENRR and CO2 reduction reaction.

Automated summary

In this study, the modification of the d-band structure of self-supporting nanoporous Mo4P3 catalyst with a hydrophobic layer successfully suppressed the hydrogen evolution reaction (HER) and improved the active sites and NH3 yield of the ENRR process. The hydrophobization method offers a promising strategy for enhancing the performance of ENRR and could be applied to a variety of metal catalysts.