Carbon quantum dots enhanced high valence matel oxidation for decontamination

Abstract. Fe(VI) demonstrates remarkable versatility in water purification, with ongoing efforts to enhance its efficacy in removing pollutants. Recent investigations have revealed that, alongside intermediate iron species [Fe(IV)/Fe(V)], direct electron transfer (DET) plays a pivotal role in organic pollutant degradation within the Fe(VI)/carbon quantum dots (CQDs) system. Initially, 30 μM of Fe(VI) oxidized approximately 52% of phenol. Upon introduction of CQDs (4 mg/L), the oxidation rates increased significantly to 87%. CQDs not only mitigated the adverse effects of solution pH on Fe(VI) pollutant abatement but also acted as catalysts, facilitating DET from organic pollutants to Fe(VI). Notably, DET mediated by CQDs proved to be a more efficient means of utilizing Fe(VI)'s oxidation potential compared to iron species oxidation alone. This DET mechanism offers a promising avenue for enhancing pollution control capabilities of Fe(VI).