Organic superconductor modified NH2-UiO-66 for boosting photocatalytic Cr(vi) elimination under low-power ultraviolet light

NH2-UiO-66@TCNQ composites (NUxTCy) were fabricated from NH2-UiO-66 and organic superconductor 7,7,8,8-tetracyanoquinodimethane (TCNQ) by a green ball-milling method. The as-prepared optimum NU90TC10 demonstrated 100% photocatalytic Cr(vi) reduction at an initial concentration of 5 mg L-1 within 50 min under low-power ultraviolet (UV) light. All experiments confirmed that the introduction of low dosage TCNQ into NH2-UiO-66 could promote Cr(vi) elimination. The results of electron spin resonance (ESR) tests, photochemical Pt(0 )deposition and electrochemical experiments confirmed that the TCNQ superconductor could improve the photocatalytic Cr(vi) removal by accelerating the separation of charge carriers over NH2-UiO-66. The factors influencing the photocatalytic Cr(vi) elimination over NU90TC10, like pH, hole scavengers and foreign ions, were investigated. The NU90TC10 composite demonstrated excellent stability and practicability up to five cycles. This work provided a new photocatalyst candidate for boosted photocatalytic Cr(vi) elimination under low power LED light.

Automated summary

NH2-UiO-66@TCNQ composites were synthesized using a green ball-milling method. The optimized NU90TC10 demonstrated excellent photocatalytic reduction of Cr(VI) under low-power ultraviolet light, and the introduction of TCNQ promoted the elimination of Cr(VI) over NH2-UiO-66.