Hydrogen Peroxide Assisted Electrooxidation of Benzene to Phenol over Bifunctional Ni–(O–C<sub>2</sub>)<sub>4</sub> Sites
Shengbo Zhang, Meng Jin, Hui Xu, Wenyi Li, Yixing Ye, Tongfei Shi, Hongjian Zhou, Chun Chen, Guozhong Wang, Yunxia Zhang, Yue Lin, Lirong Zheng, Haimin Zhang, Huijun Zhao
Abstract
Abstract Direct electrocatalytic oxidation of benzene has been regarded as a promising approach for achieving high‐value phenol product, but remaining a huge challenge. Here an oxygen‐coordinated nickel single‐atom catalyst (Ni–O–C) is reported with bifunctional electrocatalytic activities toward the two‐electron oxygen reduction reaction (2e − ORR) to H 2 O 2 and H 2 O 2 ‐assisted benzene oxidation to phenol. The Ni–(O–C 2 ) 4 sites in Ni–O–C ar proven to be the catalytic active centers for bifunctional 2e − ORR and H 2 O 2 ‐assisted benzene oxidation processes. As a result, Ni–O–C can afford a benzene conversion as high as 96.4 ± 3.6% with a phenol selectivity of 100% and a Faradaic efficiency (FE) of 80.2 ± 3.2% with the help of H 2 O 2 in 0.1 m KOH electrolyte at 1.5 V (vs RHE). A proof of concept experiment with Ni–O–C concurrently as cathode and anode in a single electrochemical cell demonstrates a benzene conversion of 33.4 ± 2.2% with a phenol selectivity of 100% and a FE of 44.8 ± 3.0% at 10 mA cm −2 .