Self-assembly synthesis of CuSe@graphene-carbon nanotubes as efficient and robust oxygen reduction electrocatalysts for microbial fuel cells

The exploration and design of inexpensive noble-free metal catalysts with high activity and stability as alternatives for carbon supported platinum catalysts (Pt/C) in the microbial fuel cells (MFCs) still remain a great challenge. In this work, nanostructured hexagonal klockmannite copper selenide (CuSe) grown on the hybrid of reduction oxidized graphene (rGO) and carbon nanotubes (CNTs) has been synthesized via a facile and cost effective method. Compared with the pure CuSe, rGO-CNTs and correlative others, the as-prepared CuSe@rGO-CNTs exhibited a superior ORR catalytic performance, for instance, more positive onset potential, higher current density, smaller Tafel slope and excellent stability. Furthermore, MFCs equipped with CuSe@rGO-CNTs cathodes also achieved a larger energy output comparable to those of reference devices employing Pt/C as the catalyst.