Coral-shaped PtRu/Ni(OH)2electrocatalyst promotes selective hydrogenation of benzoic acidElectronic supplementary information (ESI) available. See DOI: https://doi.org/10.1039/d3cy00364g

A series of 3D self-standing PtRu/Ni(OH)2/NF electrodes is fabricated for electrocatalytic hydrogenation (ECH) of benzoic acid (BA) to cyclohexanecarboxylic acid (CCA). The PtRu/Ni(OH)2electrocatalyst with a unique coral-shaped architecture possesses outstanding charge transfer ability and abundant active sites. The optimized electrode achieves a BA conversion of 99.00% and a CCA selectivity of 100% in 0.05 M H2SO4within 80 min, showing a record faradaic efficiency of 43.90% and high performance during 20 cycles of ECH. In situRaman tests verify the mechanism of the selective hydrogenation of the aromatic ring and density functional theory (DFT) calculations reveal that the electronic interaction between Pt and Ru in the PtRu nanoalloy as well as the electron transfer from the PtRu alloy to the Ni(OH)2nanosheet tunes the electronic states of PtRu/Ni(OH)2, thereby enhancing the adsorption strength of BA on the electrocatalyst surface. This work offers a promising alternative to the traditional catalytic hydrogenation of BA.