Lamellar and Conductive Ion Associations Advance the Electrochemical Catalytic Performance of Palladium

Engineering non-Pt electrocatalysts that are accompanied with superior activity and durability toward methanol oxidation reaction (MOR) remains a great challenge. In this work, a lamellar and conductive ion association is easily formed by mixing Na2PdCl4, (NH4)(6)Mo7O24, and cetyltrimethylammonium bromide (CTAB), designated as PdMoCTAB. Through tuning the amounts of precursors, three kinds of palladium (Pd) supported by lamellar ion association are fabricated by a facile hydrothermal method. Surprisingly, when the atomic ratio of Pd and Mo is 1.8:1, the resultant Pd/PdMoCTAB (denoted as Pd1.8Mo) presents great catalytic performance for MOR in an alkaline medium with a high peak current density of 2178 mA.mg(metal)(-1). The mechanism could be due to the high loading efficiency of Pd on the great surface of ion association, rapid mass transferring in the lamellar structure, and abundant strain defects of Pd induced by the deformation of ion association as well as the good conductivity of PdMoCTAB. Pd1.8Mo also shows improved stability, whereby the current density maintains 104 mA.mg(metal)(-1) after electrochemical catalysis for 10,000 s and, after 500 cycles, the mass activity retains about 64% of the initial value. Such conductive and lamellar PdMoCTAB ion association is expected to become a promising support to load various noble metals for preparing excellent electrochemical catalysts.