Structural Refinement and Optoelectrical Properties of Nd 2 Ru 2 O 7 and Gd 2 Ru 2 O 7 Pyrochlore Oxides for Photovoltaic Applications.

High-performance photovoltaic devices require active photoanodes with superior optoelectric properties. In this study, we synthesized neodymium ruthenate, Nd 2 Ru 2 O 7 (NRO), and gadolinium ruthenate pyrochlore oxides, Gd 2 Ru 2 O 7 (GRO), via the solid-state reaction technique, showcasing their potential as promising candidates for photoanode absorbers to enhance the efficiency of dye-sensitized solar cells. A structural analysis revealed predominantly cubic symmetry phases for both materials within the Fd - 3m space group, along with residual orthorhombic symmetry phases (Nd 3 RuO 7 and Gd 3 RuO 7 , respectively) refined in the Pnma space group. Raman spectroscopy further confirmed these phases, identifying distinct active modes of vibration in the predominant pyrochlore oxides. Additionally, a scanning electron microscopy (SEM) analysis coupled with energy-dispersive X-ray spectroscopy (EDX) elucidated the morphology and chemical composition of the compounds. The average grain size was determined to be approximately 0.5 µm for GRO and 1 µm for NRO. Electrical characterization via I-V measurements revealed that these pyrochlore oxides exhibit n-type semiconductor behavior, with conductivity estimated at 1.5 (Ohm·cm) -1 for GRO and 4.5 (Ohm·cm) -1 for NRO. Collectively, these findings position these metallic oxides as promising absorber materials for solar panels.