文献速递|北京师范大学JHM:用芳基胍武装的共价有机框架原位自清洁去除新出现的有机污染物

第一作者：Ruifang Qi

通讯作者：冯成洪 副教授

通讯单位：北京师范大学环境学院

DOI:10.1016/j.jhazmat.2024.137073

Fig. 1. (a) Contributions of adsorption and photocatalysis to PRO removal by the as-prepared materials (light off for 30 min; light on for 40 min). (b) The residual total organic carbon curves and the removal rate of PRO with Aryl-BIG-COF upon visible-light irradiation. (c) The pseudo-first-order rate constants (kobs) of the photocatalytic process. (d) The adsorption mechanism between Aryl-BIG-COF and PRO (left figure) and the performance of postadsorption photocatalytic degradation and direct photocatalysis for PRO with Aryl-BIG-COF (right figure). Experimental conditions: [PRO]0 =20.0 mg·L-1, [catalyst dosage] =0.2 g·L-1, T =293±1 K, and initial pH = 6.1. Data points and error bars are average values/standard errors of the mean, where n = 3.

Fig. 2. (a) Adsorption capacity and photocatalytic degradation kinetics fitting results of PRO by Aryl-BIG-COF in different water matrices. (b) Photocatalytic degradation and comparison of pseudo-first-order kinetic rate constants (inset) at different pH values of PRO over Aryl-BIG-COF upon visible-light irradiation. (c) Photocatalytic degradation performance of Aryl-BIG-COF for other emerging contaminants. (d) Comparative efficiency analysis of Aryl-BIG-COF with other reported photocatalysts for the degradation of PRO. The equivalent efficiency (EE) was calculated via the following equation: EE = (Initial concentration × Efficiency)/(Dosage × Time) (h-1), which indicates the number of milligrams of pollutants that can be degraded per gram of catalyst per hour.

Fig. 3. (a) In situ recycling stability of Aryl-BIG-COF in the photocatalytic degradation of PRO after six cycles. Experimental conditions: [catalyst dosage] =0.2 g·L−1; [PRO]0 = 20.0 mg·L–1. (b) High-performance liquid chromatography of the eluents of Aryl-BIG-COF after adsorption equilibrium and adsorption–catalytic equilibrium. (c) Comparison of FT-IR spectra and (d) XRD patterns of Aryl-BIG-COF before and after catalysis. (e) The highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) distributions, and electrostatic potential (ESP) mapping of PRO. (f) The proposed transfer process and photocatalysis pathway of PRO with Aryl-BIG-COF. (g) Theoretically calculated bioaccumulation factor of PRO and the corresponding intermediates predicted by T.E.S.T. with the consensus method.

Fig. 4. (a) Transient photocurrent response, (b) fitted electrochemical impedance spectra (EIS) Nyquist plots, and (c) time-resolved photoluminescence (TRPL) spectra of the as-prepared materials. (d) Electron paramagnetic resonance (EPR) spectra of the photocatalytic system after 15 min of visible light irradiation. (e) Effects of different quenching agents on PRO degradation and (f) the pseudo-first-order kinetics rate constant (columns, primary y-axis) for PRO and the contributions (symbols, secondary y-axis) of different free radicals. Experimental conditions: [PRO]0 =20.0 mg·L-1, [catalyst dosage] =0.2 g·L-1, initial pH = 6.1, [TBA] = 0.5 M, [FFA] = 2.0 mM, [EDTA-2Na] = 2.0 mM, and [p-BQ] = 2.0 mM. (g) Tauc plot in the form of (αhυ)2 versus hυ and (h) MottSchottky plots for as-prepared materials. (i) Regulation of the energy band structure and PRO photocatalytic degradation over COFs under visible light irradiation. (j) Electrostatic potential (ESP) mapping and quantitative distribution of ESPs on the vdW surface of COFs. (k) Highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) distribution diagrams of COFs. (l) Oscillator strength and molar absorption coefficient of fluorescence emission from the S1 excited state for COFs. (m) Charge density difference between the S1 excited state and the ground state and at an isovalue of 0.001 a.u. (Green and blue represent increasing and decreasing regions of electron density, respectively. The quantitative charge-transfer analysis is based on the interfragment charge transfer method. Sr represents the geometric mean of the degree of overlap between electron and hole distributions under electronic excitation.).

Fig. 5. Analysis of the enhanced photocatalytic performance of Aryl-BIG-COF for removing PRO based on the electron excitation and charge carrier utilization via DFT calculations.