The effect of SnO2 on enhancing electrocatalytic property of palladium toward formic acid oxidation

Although palladium (Pd) based materials are considered the best catalyst for formic acid oxidation reaction (FAOR), they are still confronted with a lot of barriers, such as the growth/sintering of Pd nanoparticles (NPs) and the accumulation of adsorbed poisoning intermediates. Herein, tin dioxide (SnO 2 ) decorated carbon black was utilized as the catalyst carrier to synthesize Pd/SnO 2 /C for FAOR. The introduction of SnO 2 significantly reduced the particle size of Pd NPs and forming the Pd–O–Sn structure. Compared with Pd/C, Pd/SnO 2 /C owned higher concentration of O ads and less adsorption amount of poisoning intermediates. The oxygen atoms adsorbed on Pd surface were rapidly transferred to SnO 2 due to the spillover effect. The FAOR reaction kinetic results showed that the introduction of SnO 2 accelerated the diffusion rate of formic acid on the electrode surface . Pd/SnO 2 /C exhibited high specific activity (5.97 mA cm −2 ), excellent durability, and high anti-CO poisoning ability toward FAOR due to the introduction of SnO 2 .