Efficient detection and degradation of hexavalent chromium wastewater in tourist attractions using dual-fluorescent UiO-66-NH2 stabilized polysulfone Pickering emulsions

Abstract

This investigation delineates the synthesis of a novel, bifunctional composite material, embedding cadmium telluride (CdTe) and carbon quantum dots (CQDs) within the metal-organic framework UiO-66-NH₂, fabricated through a Pickering emulsion technique to augment the photocatalytic degradation and detection of hexavalent chromium (Cr(VI)). We elucidate that the integration of these quantum dots substantially narrows the bandgap energy of UiO-66-NH₂ to 1.76 eV for CQDs and 2.83 eV for the composite, thereby enhancing the spectrum of visible light absorption and fortifying charge carrier separation. The foundlings reveal a pronounced elevation in photocatalytic performance, with the composite material accomplishing up to 90 % reduction of Cr(VI) within 200 min under visible light exposure. Moreover, the composite demonstrates robust reusability, sustaining efficacious degradation across numerous cycles with minimal attenuation in activity. The composite material can detect and degrade Cr(VI) in the environment, providing an efficient means of heavy metal pollution remediation for tourist attractions. It is economical and sustainable, aligning with the green and low-carbon tourism development concept.