Inhibition of In Situ Formed Ni(OH)2 on a Pd/Ni Foam Cathode for Efficient Electrocatalytic Hydrodechlorination of Clofibric Acid

• Published in: Industrial & engineering chemistry research 2023-08, Vol.62 (30), p.11862-11871
• Main Authors: Wang, Zheni, Chen, Hongxu, Yan, Chen, Lou, Zimo, Li, Cheng, Zhang, Shuangyu, Hu, Yunxuan, Xu, Xinhua
• Format: Article
• Language: English
• Subjects: Kinetics, Catalysis, and Reaction Engineering
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/acs.iecr.3c01638

Electrocatalytic hydrodechlorination (ECH) based on Pd-modified Ni foam electrodes offers a sustainable approach for decontaminating halogenated chlorinated organics, but the synthesis of Pd/Ni foam is always poorly controlled. In this work, with clofibric acid (emerging as a typical pharmaceutical) as a probe contaminant, we show that the ECH performance of Pd/Ni foam is highly dependent on the impregnation time during its preparation. During preparation, the dissolved Ni2+ can combine with aqueous OH– to form in situ Ni­(OH)2 coatings on Pd/Ni foam. By prolonging the impregnation time, continuous deposition of Ni­(OH)2 gradually increases the anti-corrosive property and the electrochemically active surface area of the electrode. However, such covered Ni­(OH)2 coatings promote the interfacial charge transfer resistance and hinder the atomic H* adsorption by Pd, which is detrimental to ECH. This work provides a novel strategy for the synthesis of Pd/Ni foam electrodes with an enhanced ECH property for electroreductive remediation of chlorinated pharmaceutical compounds.