Photoelectrochemical and photosensing study of nitrogen doped carbon nanoparticles sensitized TiO2 nanorods

Nitrogen doped Carbon Nanoparticles (NCNPs) were synthesized using a thermal pyrolysis method. NCNPs are crystalline in nature with diameter ranges from size 9–36 nm. Optical absorption study revealed two major peaks. The sharp peak at 220 nm is attributed to π → π* transition in aromatic sp2 CC bonds and the broad peak at 300–400 nm corresponds to n → π* transition in C=O/C=N bonds. NCNPs are highly luminescent and demonstrated excitation dependent green photoemission under 340-500 nm photoexcitation. TiO2 nanorods (TiO2 NRs) were grown on Fluorine doped tin oxide (FTO) coated glass substrates using hydrothermal method. Photoelectrochemical properties of pristine TiO2 NRs and NCNPs sensitized TiO2 NRs has been studied in detail. NCNPs sensitized nanorods demonstrated superior photoconversion efficiency (η) of 1.37% and incident-photon-to-current conversion efficiency (IPCE) of 80% at 340 nm.