Hydrothermally synthesized Mo/Zr MOF photocatalyst for promoting the removal of Cr⁶⁺

The development of highly efficient photocatalysts for the degradation of organic dyes and heavy metal ions is necessary to control pollution in the environment and further protect human health. This paper reports nmolybdenum (Mo)/zirconium (Zr) metal–organic frameworks (MOFs) (n = 1, 2, 3 and 4; nMZMs) synthesized by using a simple hydrothermal method for efficient photocatalytic chromium (VI) (Cr6+) ion reduction for the first time. Among all the prepared samples, 2MZMs show the highest photocatalytic performance with degradation rates of 94.36% for methylene blue and 91.20% for chromium (VI) ions under visible light irradiation for 120 and 100 min, respectively. Electron spin resonance experiments reveal that •O2 − and •OH play a major role. This finding proves great potential for the design and application of MOF nanomaterials and might bring considerable application prospects for photocatalysis of organic pollutants and heavy metal ions in polluted water.