PdCu nanoparticles modified free-standing reduced graphene oxide framework as a highly efficient catalyst for direct borohydride-hydrogen peroxide fuel cell.

A novel electrode of PdCu nanoparticles modified free-standing reduced graphene oxide (rGO) framework (PdCu@rGOF) is fabricated via electrodeposition and chemical reduction and employed to the direct sodium borohydride-hydrogen peroxide fuel cell (DBHPFC). The resultant catalyst reveals excellent catalytic performance towards hydrogen peroxide (H 2 O 2) electroreduction reaction (HPRR) and sodium borohydride (NaBH 4) electrooxidation reaction (BOR) along with low activation energy (E a). Numerically, the PdCu@rGOF electrode delivers an HPRR current density of 455.2 mA cm−2 at 0 V (2 mol L−1 H 2 SO 4 +1.3 mol L−1 H 2 O 2). Additionally, the current density of BOR reaches up to 1065.3 mA cm−2 at 0 V for 2 mol L−1 NaOH and 0.3 mol L−1 NaBH 4. Meanwhile, the mechanism studies show that HPRR and BOR catalyzed by PdCu@rGOF mainly relates 2-electron-transfer process and quasi-8-electron-transfer process, respectively. Subsequently, PdCu@rGOF is assembled into a fuel cell, yielding the optimal power density of 188.9 mW cm−2. The open circuit potential (OCP) of DBHPFC is about 1.70 V at 293.15 K. The superior electrochemical performance of the optimized electrode can be attributed to the distinctive architecture and the strong adsorption and bond-breaking ability of Pd nanoparticles. This work indicates that the as-prepared PdCu@rGOF can be a promising catalyst for DBHPFC. [Display omitted] • A novel 3D through-hole rGOF framework has been successfully prepared. • PdCu@rGOF displays an excellent catalytic performance for HPRR and BOR. • PdCu@rGOF can be applied to both anode and cathode of DBHPFC. • DBHPFC presents high power density and operation stability. [ABSTRACT FROM AUTHOR]