Pd Nanoparticles with Twin Structures on F‐Doped Graphene for Formic Acid Oxidation

The formic acid oxidation (FAO) on palladium (Pd) particles is relevant with their crystal structures. Here, silicon nanowires are employed as a sacrifice template to grow Pd nanoparticles with various twin structures, including two‐fold, three‐fold and five‐fold ones, as confirmed by the high‐resolution TEM image. These nanoparticles are well dispersed on the semi‐ionic fluorine (F) ions doped reduced graphene oxides, which have high activity toward FAO due to their appropriate binding energy to intermediates. The as‐prepared products show an excellent performance on FAO. The peak current of the optimal product is 0.697 A ⋅ mgPd−1 in 0.1 M HClO4 and 0.5 M HCOOH, which is 2.9 times than that of the commercial Pd/C catalyst. The electrochemical active surface area of the catalyst (0.322 m2 ⋅ mg−1) is 3.5 times than that of the commercial Pd/C (0.091 m2 ⋅ mg−1). This outstanding performance is due to the twin structure of Pd nanoparticles and the electron‐deficient surface caused by the strong electrophilicity of F ions.