Oxygen vacancies-rich Co3O4 cones loaded low content Pd for efficient and fast electrocatalytic hydrodechlorination

Abstract

Pd-based materials have been considered to be the preferred electrocatalysts for electrocatalytic hydrodechlorination (EHDC) due to their excellent H* production capacity. However, the scarcity and high price of Pd restrict its use, thus, an efficient Pd-based EHDC electrocatalyst with low Pd content should be developed. In this work, oxygen vacancies-rich Co3O4 (Co3O4-OV) cone-like architecture growth in situ on Ni foam was used as an intermediate layer to synthesize Pd@Co3O4-OV/NF EHDC electrocatalyst with low Pd loading (0.0254 mg cm−2). Pd@Co3O4-OV/NF electrocatalyst can obviously promote the H* production and shows high EHDC activity with a dechlorination activity (DA) of 2.07 mmol2,4-DCP gPd−1 min−1 for EHDC of 2,4-dichlorophenol, which is higher than most reported Pd-modified electrodes. The Pd@Co3O4-OV/NF exhibited excellent anti-background interference ability (different initial pH and anions in aqueous solution) and good cycle stability (5 consecutive EHDC cycles), which could effectively improve aquatic biosafety.