Interstitial boron-doped nanoporous palladium film for electro-reduction of nitrogen to ammonia

Electrocatalytic nitrogen reduction to ammonia has attracted abundant research interest due to its mild operation condition and sustainable feedstock. The identification of efficient catalysts with high selectivity of nitrogen reduction is the key for the electro-synthesis of ammonia. Herein, interstitial boron-doped nanoporous palladium film is directly formed on Ni foam (nPdB/NF) via micelle-assisted reduction method using borane dimethylamine complex as reducing agents and boron dopant. The binder-free nanoporous structure provides abundant active sites and facilitated mass/charge transfer. Moreover, the introduction of interstitial boron atoms can modify the electronic structure of Pd, which can both improve the nitrogen adsorption and inhibit hydrogen evolution on nPdB/NF. As such, nPdB/NF exhibits high NH3 yield of 29.0 mu g h-1 mg-cat.1 and Faraday efficiency of 17.9% in 0.1 M Na2SO4, superior to that of nPd/NF (19.7 mu g h-1 mg- 1 cat and 14.7%). This work offers an attractive method for the introduction of interstitial boron into Pd-based catalysts to improve NRR performance.

Automated summary

In this study, an interstitial boron-doped nanoporous palladium film was directly formed on Ni foam via a micelle-assisted reduction method. The binder-free nanoporous structure provides abundant active sites and facilitated mass/charge transfer. Moreover, the introduction of interstitial boron atoms can modify the electronic structure of Pd, improving nitrogen adsorption and inhibiting hydrogen evolution, thus enhancing the efficiency of nitrogen reduction reaction.