Target identification and degradation of trace chlorinated disinfection by-products through an innovative nano-island-molecular imprinting strategy: Target selectivity and generalizability

Chlorinated by-products (Cl-DBPs) generated during drinking water disinfection are characterized by high toxicity, low concentration (ppb level), and difficult to be removed under environmental disturbances. However, traditional adsorption or in situ degradation technologies remain ineffective in achieving efficient removal. This study developed a novel treatment material (Fe-Ir/ZnO x @BC-MIP) that can both precisely identify and efficiently degrade chlorinated phenolic disinfection by-products (CPs-DBPs). By synergistically combining molecular imprinting technology (MIT) and asymmetric bimetallic electronic structures, this treatment achieves dual removal functionality for CPs-DBPs. Nearly all trace amounts of CPs-DBPs in drinking water have achieved complete mineralization. The molecularly imprinted cavity constructed by this material using the 2’4’6-trichlorophenol (TCP) template achieves specific recognition of CPs-DBPs through C-OH hydrogen bonds (-0.80 eV) and π-π interactions (-0.85 eV), with the targeted adsorption efficiency of the imprinted material being approximately 1.5 times higher than that of non-imprinted materials. Additionally, the anchored Fe-O-Ir bimetallic sites within ZnO x nanoislands form electron-deficient and electron-rich active centers, inhibiting the complexation rate of charge carriers and stimulating the generation of free radicals (•O 2 - and •OH) to accelerate the degradation of captured substances. Furthermore, the catalytic reactor maintained a 92 % TCP removal efficiency after continuous operation for 2220 min in a flow-through column experimental setup, demonstrating excellent stability and durability. This study provides a new method for the targeted removal and detoxification of trace CPs-DBPs in complex water bodies.