An exceptional amorphous nanoscale Pd/carbon cloth composite electrode for energy-saving oxalic acid electrolysis coupled with hydrogen production

Abstract

In this paper, we report a carbon cloth/amorphous nanoscale Pd (CC/AN Pd) composite electrode and realizes the modifier-free composite of low-cost intractable carbon support and low-loading Pd metal by designing a mild and facile oxidation-ion exchange-reduction (OIR) route. This CC/AN Pd composite electrode presents high activity, robust, cost-effective, modifier-free, micro-nano porous and low Pd loading characteristics compared with the traditional Pd/C electrode. This composite electrode shows superior oxalic acid (OA) oxidization reaction (OOR) catalysis performance, outperforming all the as-reported OOR catalysts especially at high current density. Moreover, on the basis of catalysis performance and the cost of Pd loading amount, this CC/AN Pd composite electrode shows superior hydrogen evolution reaction (HER) catalysis performance with high cost-effective characteristic, surpassing all the as-reported HER catalytic electrodes. Importantly, this composite electrode was used as HER and OOR electrodes to assemble an oxalic acid electrolytic cell (OAEC), which drives 10 mA/cm2 and 100 mA/cm2 current density at only 1.09 V and 1.52 V voltage, respectively, and obtains up to 95.2% average faraday efficiency for 50 mA/cm2 oxalic acid electrolysis. Notable, this CC/AN Pd composite electrode-based OAEC has better energy-saving and stability advantage compared with the commercial CC/Pd–C-based OAEC especially for high current density OA electrolysis. This work opens new avenues to the design of novel composite electrode materials and enables new opportunities in green energy or environmental catalysis areas.