The superior piezo-photocatalytic performances of KNbO3-based materials were achieved by the enhanced photo-induced carrier separation and migration based on the effective strategies of heterojunction construction and polarization engineering. A KNbO3/WO3 type-II heterojunction was fabricated by an impregnation-calcination method, and its outstanding piezo-photocatalytic performance was demonstrated. Compared to individual KNbO3 and WO3, KNbO3/WO3 composites exhibited better degradation performance for RhB solution under visible light irradiation, and the degradation rate of 30%KNbO3/WO3 composite for RhB solution was 98% within 80 min (its reaction rate constant k was 0.03894 min−1). Inspiringly, the polarized 30%KNbO3/WO3 composite degraded RhB solution completely within 60 min under visible light irradiation with auxiliary ultrasonic activation, and its reaction rate constant was up to 0.0612 min−1 (3.35 times that of individual KNbO3). The synergistic effects of heterojunction construction, polarization engineering, and ultrasonic vibration in KNbO3/WO3 composite were confirmed, and the multi-electric fields in polarized KNbO3/WO3 heterojunction significantly enhanced carrier separation, thus promoting piezo-photocatalysis. This work proposes an important strategy for designing multi-electric field-driven ferroelectric-based heterojunction photocatalysts.

中文翻译：

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高协同极化 KNbO3/WO3 异质结用于压电光催化降解有机污染物


基于异质结构建和极化工程的有效策略，通过增强光诱导载流子分离和迁移，实现了 KNbO3 基材料的优异压电光催化性能。采用浸渍-煅烧法制备了KNbO3/WO3 II型异质结，证明了其出色的压电光催化性能。与单个 KNbO3 和 WO3 相比，KNbO3/WO3 复合材料在可见光照射下对 RhB 溶液表现出更好的降解性能，30% KNbO3/WO3 复合材料对 RhB 溶液的降解率在 80 分钟内为 98%（其反应速率常数 k 为 0.03894 min−1）。令人鼓舞的是，极化的 30%KNbO3/WO3 复合材料在可见光照射下在辅助超声激活下在 60 min 内完全降解了 RhB 溶液，其反应速率常数高达 0.0612 min−1（单个 KNbO3 的 3.35 倍）。证实了 KNbO3/WO3 复合材料中异质结构建、极化工程和超声振动的协同效应，极化 KNbO3/WO3 异质结中的多电场显著增强了载流子分离，从而促进了压电光催化。这项工作为设计多电场驱动的基于铁电的异质结光催化剂提出了一种重要的策略。