Performance improvement of activated nanoporous carbon supported gold catalyst as an anode for direct borohydride–hydrogen peroxide fuel cells

Abstract

Activated nanoporous carbon (A-NPC) has been synthesized via KOH activation of a nanoporous carbon (NPC) prepared using a template metal–organic framework-5 (MOF-5), and it is firstly used as an anode electrocatalyst carrier of Au nanoparticles in borohydride–hydrogen peroxide fuel cells (DBHFCs). The samples are characterized by N₂ adsorption–desorption isotherms, transmission electron microscopy (TEM), X-ray diffraction (XRD), cyclic voltammetry (CV), chronopotentiometry (CP), chronoamperometry and fuel cell tests. It has been found that the A-NPC achieves a surface area up to 2296 m² g⁻¹ and a pore volume of 1.59 cm³ g⁻¹. The mean particle size of Au crystallites dispersed uniformly on the surface of the A-NPC carrier is only 2.9 nm. Besides, the peak current density for direct borohydride oxidation of the Au/A-NPC (49.1 mA cm⁻²) is 13.6% higher than that of the untreated NPC supported Au (43.2 mA cm⁻²), and 63.1% higher than that of commercial Vulcan XC-72R supported Au (30.1 mA cm⁻²). The DBHFC using the Au/A-NPC as anode electrocatalyst can obtain a maximum power density of 48.2 mW cm⁻² at 25 °C.