Self-catalytic induced interstitial C-doping of Pd nanoalloys for highly selective electrocatalytic dehydrogenation of formic acid

Light-metalloid-atom-doped Pd interstitial nanoalloy is promising candidate for electrocatalysis because of the favorable electronic effect. Herein, an innovative method was developed to synthesize C-doped Pd interstitial nanoalloy using palladium acetate both as metal precursor and C dopant. Elaborate characterizations demonstrated that C atoms were successfully doped into the Pd lattice via self-catalytic decomposition of acetate ions. The as-synthesized C-doped Pd catalysts showed excellent activity and durable stability for formic acid electrooxidation. The mass activity and specific activity at 0.6 V of C-doped Pd were approximately 2.59 A/mg and 3.50 mA cm−2, i.e., 2.4 and 2.6 times of Pd, respectively. DFT calculations revealed that interstitial doping with C atoms induced differentiation of Pd sites. The strong noncovalent interaction between the Pd sites and the key intermediates endowed Pd with high-selectivity to direct routes and enhanced CO tolerance. This work presents a sites-differentiation strategy for metallic catalysts to improve the electrocatalysis.