First investigation on (Ni, Co) co-doping effects on the physical properties of Fe2O3 thin films for optoelectronic applications

A simple chemical spray pyrolysis technique was used to fabricate Ni and Co co-doped Fe2O3 thin films. All the co-doped layers are formed of alpha-Fe2O3 phase. The influence of the dual doping on the physical properties of the as deposited layers was investigated. The SEM and CM images revealed that co-doping changed the surface morphology of the Fe2O3 films. The main particle shape and size were significantly influenced by each dopant. The Optical measurement showed that the band gap varies in the range of [1.99-2.16] eV for direct transition and in the domain of [1.87-1.96] eV for indirect transition, it is affected by the dopant concentrations. The photocatalytic degradation of methylene blue dye under sunlight irradiation was investigated for all the grown layers. The obtained result showed high photocatalytic efficiency. The (Ni 2%, Co 1%) co-doped Fe2O3 thin films showed a degradation efficiency around 50 % after 2 h of sunlight irradiation.