A high-performance type-II MIL/BiVO4 heterojunction: a robust photocatalyst for efficient Cr(vi) detoxification

Abstract

To address the issues of low efficiency and complex processes in traditional chromium pollution control technologies, a MIL/BiVO₄ heterojunction composite photocatalyst was constructed via hydrothermal in situ growth. This structure effectively promotes the separation of photo-generated charges, achieving complementary advantages between the two components, thereby significantly enhancing the photocatalytic reduction activity and efficiency toward Cr(VI). The MIL/BiVO₄ heterojunction achieved a reduction rate of nearly 100% towards hexavalent chromium within 15 minutes under the optimized conditions (UV irradiation, 15 mg of catalyst, 2 mM hexavalent chromium, and 0.7 mL of formic acid). After five cycles of reuse, the material retains over 95% of its catalytic activity, demonstrating excellent stability and reusability. This study provides new insights into developing highly efficient and sustainable materials for heavy-metal pollution remediation.