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For the practical implementation of Cr(Ⅵ) removal, effective and recyclable water treatment technology is essential. Polarized electric fields inside piezoelectric materials have proved to be a promising technique for facilitating photogenerated charge separation. In this work, Z-scheme heterojunction photocatalyst HKUST-1/BiVO 4 and organic piezoelectric material PVDF were combined through electrospinning to create a novel flexible fiber PVDF-HKUST-1/BiVO 4 (PVDF-HV) piezo-photocatalyst membrane. When the amount of HKUST-1/BiVO 4 powder was 2.4% and the diameter of the obtained fiber film was 10 cm, the optimal reduction efficiency can be achieved by the piezoelectric photocatalytic reduction in solution with initial pH=2, and the piezo-photocatalytic efficiency of PVDF-HV reached up to 85.33% within 120 min, which was about 1.35 times and 2.19 times greater than that of single photocatalysis and piezoelectric catalysis, respectively. It successfully promoted photo charge separation based on the piezoelectric field in PVDF and the heterojunction produced between HKUST-1 and BiVO 4. This research developed an efficient strategy for multi-path collection and exploitation of natural solar energy and vibration energy to boost photoactivity. [Display omitted] • Z-scheme HKUST-1/BiVO 4 and piezoelectric PVDF were combined through electrospinning. • Superior piezo-photocatalytic activity has been obtained by PVDF-HKUST-1/BiVO 4. • Synergistic effects of heterojunction and piezoelectricity was addressed. • The catalytic mechanism under ultrasound and visible light was revealed. [ABSTRACT FROM AUTHOR]

In the present study, NaNbO 3 -CdS nanorods composites with pyroelectric effect were used to degrade RhB solution and sterilize Salmonella under room-temperature cold-hot cycles. The pyrocatalytic decomposition rate of NaNbO 3 -CdS reached 90 % under 45 cold-hot (25–55 °C) cycles while the antibacterial rate of NaNbO 3 -CdS also achieved 90 % under 45 cold-hot (17–37 °C) cycles. Compared with the pyrocatalytic effect of single NaNbO 3 , with the hole's radicals and superoxide radicals as the main active species, the pyrocatalytic effect of the NaNbO 3 -CdS was significantly enhanced. It is mainly attributed to its surface electrons being captured by CdS, thereby reducing the recombination probability of electron pairs. After four repeated experiments, the high pyrocatalytic activity still maintained, which indicated that the property of NaNbO 3 -CdS composites was stable. The composite nanocatalyst has potential in the degradation of dye pollution and sterilization by temperature difference. [Display omitted] • NaNbO 3 -CdS nanorods composites with pyroelectric effect was successfully synthesized. • Pyroelectric catalytic mechanism under room-temperature cold-hot cycles was revealed. • Superior pyrocatalytic and antibacterial activity have been obtained by NaNbO 3 -CdS. • Heterojunction effectively reduces recombination of pyroelectric electrons and holes. [ABSTRACT FROM AUTHOR]