Enhanced water splitting performance of biomass activated carbon-anchored WO3 nanoflakes

Abstract

The high performance electrocatalysts is vital for enhancing the hydrogen production efficiency for water splitting. In light of this, biomass activated carbon-decorated tungsten oxide (WO3/B-AC) nanocomposites are synthesized through a simple sonochemical method. The WO3/B-AC nanocomposites show an aggregated structure of activated carbon nanosheet-encapsulated tungsten oxide nanoflakes. The WO3/B-AC nanocomposites exhibit the overpotential of 320 mV at 10 mA/cm(2) with the Tafel slope of similar to 48 mV/dec and good stability for the oxygen evolution reaction. For the hydrogen evolution reaction, the nanocomposites also show the overpotential of 360 mV at 10 mA/cm(2) with the Tafel slope of similar to 14 mV/dec and excellent durability in 1 M KOH. The superior electrocatalytic activity of the WO3/B-AC nanocomposite electrode is attributed to the synergetic effect from both the high electrical conductivity of activated carbon nanosheets and the high electrochemically-active surface area of WO3 nanoflakes. These results advocate that the sonochemically synthesized WO3/B-AC nanocomposites hold promise as excellent electrocatalysts for green energy conversion and storage applications.