(600az) An Investigation into the Bandgap and Bandedge of Semi-Conducting La-Transition Metal Perovskites for Photocatalytic Applications

The emission of greenhouse gases like CO₂ has posed dire environmental complications which has challenged researchers to find sustainable methods to eliminate CO₂ presence in the atmosphere. The ideal solution is to convert CO₂ to useful and non-toxic compounds like hydrocarbons that can be used as fuel. The photocatalytic reduction of CO₂ facilitated by solar energy has stirred up great interest over the past few decades. The desire of this study is to synthesize highly efficient and stable photocatalyst with narrow band gap energy in order to ease the emission of photoexcited electrons that will reduce CO₂ in the presence of water into energy bearing products.

The design of semi-conducting perovskites heterogeneous photocatalysis was based on the strategy of synergistic effects of B-site transition elements which also determine the catalytic activity. LaFe_xCr_1-xO₃, LaFe_xMn_1-xO₃ and LaMn_xCr_1-xO₃ (x= {1, 0.25, 0.5, 0.75}) perovskites were synthesized through Pechini process. The produced perovskites were subsequently characterized by X-ray powder diffraction technique. The samples showed high crystallinity and an assortment of cubic, hexagonal and orthorhombic crystal structures with cubic found to be a major component. The band gap energy are to be determined by ultraviolet-visible diffuse reflectance spectrophotometry.