Study of Pyrochlore Bi2Ti2O7 Synthesized via Hybrid Method

Abstract

Pyrochlores have gained significant attention in contemporary scientific research owing to their distinctive optical properties, rendering them highly efficient across a broad spectrum of photocatalytic applications such as water remediation. Bi₂Ti₂O₇ nanopowder with a pyrochlore structure is successfully synthesized through a hybrid approach combining co-precipitation and the Pechini method. The influence of this hybrid synthesis technique on the photocatalytic activity of pure Bi₂Ti₂O₇ nanopowder is extensively studied. X-ray diffraction analysis established the pyrochlore structure of the synthesized Bi₂Ti₂O₇ nanopowder with well-defined diffraction peaks. The average crystallite size is estimated to be about 16 nm. Fourier transform infra-red spectroscopy insights the functional groups present, with wavenumbers at 489 and 1380 cm^–1 corresponding to the vibrations of Bi–O bonds, and at 621 cm^–1 associated with Ti–O–Ti stretching vibrations, further substantiating the formation of Bi₂Ti₂O₇ pyrochlore. UV-Vis spectroscopy reveals a narrow bandgap of 2.72 eV, ideal for efficient photocatalytic activity under visible light. The photoluminescence spectrum demonstrated the lower charge carrier recombination rate, which influences photocatalytic performance. Insights into the photocatalytic activity of Bi₂Ti₂O₇ is acquired through the degradation of a methylene blue dye under visible light (>420 nm). The maximum degradation was achieved within a brief period of 50 min with the apparent reaction rate constant of the catalyst 12.3 × 10^–3 min^–1. These findings highlight the potential of Bi₂Ti₂O₇ as a promising photocatalyst for a wide range of environmental applications, including wastewater treatment and the removal of organic pollutants.