Nanostructured BiOI-GO composite: facile room temperature synthesis with enhanced multifunctionality in field emission and photocatalytic activity

Coupling of layered semiconductors with graphene-based materials could enable enhanced performance as compared to the pristine counterparts. Herein, we report enhanced multifunctional behaviour of a bismuth oxyiodide-graphene oxide (BiOI-GO) composite regarding its field emission and photocatalytic characteristics. The layered bismuth oxyiodide (BiOI) nanodiscs and nanostructured BiOI-GO composite were synthesized at room temperature employing a facile, single step precipitation method. The as-synthesized products were characterized using XRD, SEM, TEM, and a Raman spectrophotometer so as to reveal their phase, morphological and structural properties. Field emission (FE) studies of pristine layered BiOI nanodiscs and BiOI-GO nanocomposite emitters were carried out at the base pressure of similar to 1 x 10(-8) mbar. The values of turn on field required to draw an emission current density of 10 mu A cm(-2) are found to be 2.7 and 1.2 V mu m(-1) for BiOI nanodiscs and BiOI-GO nanocomposite emitters, respectively. Extraction of an emission current density of similar to 1150 mu A cm(-2) from the BiOI-GO nanocomposite emitter at the remarkably low applied field of 2.8 V mu m(-1) signifies its enhanced FE performance. The superior FE characteristics of the BiOI-GO nanocomposite emitter are attributed to modulation of the electronic properties due to composite formation, and the high aspect ratio of the nanosheets/nanodiscs. Furthermore, the BiOI-GO nanocomposite exhibits enhanced photocatalytic activity towards degradation of methyl orange (MO) dye.