Sol-gel extended hydrothermal synthesis of BiFeO3 nano-beads for excellent photocatalytic and photo-electrochemical properties under natural light irradiation

The synthesized BiFeO3 has low cost, distinctive structure, large specific surface area, and outstanding electrical and mechanical properties, making it stable, non-toxic, and cost-effective material that can be used in photo-catalytic applications. Here, we report the successful synthesis of a pure-phase BiFeO3 nano-beads through a well-controlled sol-gel extended hydrothermal strategy. The structural, morphological, and optical properties of as-prepared BiFeO3 nano-beads were studied by X-ray Diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Brunauer-Emmett-Teller (BET) and Ultraviolet-visible-near-infrared (UV-vis-NIR) transmittance spectrophotometer. It was observed that BiFeO3 nano-beads exhibit strong absorption in the UV and visible light region and the corresponding lowest band gap has been estimated to be 2.13 eV. The photo-electrochemical (PEC) properties of the prepared photo-anodes were analyzed with electrochemical impedance spectroscopy (EIS) and chronoamperometry analysis (CA). Electron transfer of the charge carriers and transient photo-current response were enhanced for BiFeO3 -nano-beads as studied by EIS and CA. The as-prepared BiFeO3 nano-beads showed excellent photocatalytic and photo-electrochemical (PEC) properties for enhanced degradation of methylene blue (MB) and hydrogen evo-lution activity (14.7 mmol g-1 h-1) in the presence of Platinum as co-catalyst were carried out under natural light irradiation at ambient temperature.