Graphene quantum dots decorated rutile TiO_2 nanoflowers for water splitting application

摘要

Flower like rutile TiO_2 films were decorated with green-photoluminescent graphene quantum dots(GQDs) and photovoltaic properties were investigated for water splitting application. Rutile TiO_2 nanoflowers(NFs) and GQDs(average width of^12 nm) synthesized separately using a hydrothermal method and TiO_2 NFs were decorated with various amounts of GQDs solution(x = 5, 10, 15 and 20 μL) by spin coating. Optical characterization reveals that GQDs are highly luminescent and absorb UV and visible light photons with wavelengths up to 700 nm. GQDs-x/TiO_2 electrode shows a photocurrent enhancement of ~95% compared to pristine TiO_2 NFs for the optimum sample(x = 15 μL) at an applied potential of P = 0 V using 1 M Na_2SO_4 solution as electrolyte.