Significantly enhanced piezo-photocatalytic capability in BaTiO3 nanowires for degrading organic dye

Over the last several years, piezo-photocatalytic effect was intensively investigated for a facile, effective and promising protocol to sewage treatment and environmental remediation. The research on the integration of piezocatalytic and photocatalytic process on lead-free ferroelectric materials is highly demanded to further push this field forward. In this work, BaTiO3 nanowires (BT NWs) were fabricated by a two-step hydrothermal method. The degradation of organic dye (methyl orange, MO) aqueous solution (5 mg L−1) by integrating photocatalysis with the piezoelectric-like effect under UV light radiation and ultrasonic vibration was investigated. The decomposition ratio reaches up to ∼98.17% (at 80 min), which is around 1.28 and 2.24 times of the sole piezocatalysis and photocatalysis process, respectively. The intermediate product of hydroxyl radical (•OH) and superoxide radical (•O2−) was detected and quantified by radical trapping experiments, to illustrating their key role in degrading MO molecules. In addition, we carried out sequential cycles to evaluate the cycling stability and usage durability of catalysts and a reduction of ∼15% in the efficiency was observed after four cycles. This work provides a promising paradigm for the further development of piezo-photocatalytic materials and target applications in environmental field. [Display omitted] •BT NWs were prepared by a two-step hydrothermal method.•The synergistic piezo-photocatalysis realizes the efficient degradation of dyes.•Degradation rate of piezo-photocatalysis is 1.28 and 2.24 times of sole piezocatalysis and photocatalysis, respectively.•The mechanism of piezo-photocatalysis was detailed.