Two is better than one: catalytic, sensing and optical applications of doped zinc oxide nanostructures

Nanosized ZnO-based materials for catalytic and sensing applications are highly proficient over bulk catalytic analogous due to higher surface and tunable physicochemical properties. The functionality, porosity, shape, size and surface area of these nanomaterials are crucial factors for influencing specificity and efficiency of its applications. In this review, we contemplated the effect of metal doping on ZnO nanoparticles for various applications such as solar cells, photocatalysis, medicines, light-emitting diodes, laser diodes, chemical and biosensors. The potential applications of metal-doped ZnO have gained significant attention owing to direct influence by the dopants on electronic and physiochemical properties. Especially, the natural bandgap (3.37 eV) and n-type conducting behaviour of ZnO can be tuned by doping of metals/metal oxides and non-metals by replacing Zn2+ and O2- in ZnO lattices respectively. Further, the bandgap modified ZnO could be used as a multi-functional material by growing it in various nanostructures such as bulk, thin layer and wires.