Covalent Furan‐Benzimidazole‐Linked Polymer Hollow Fiber Membrane for Clean and Efficient Photosynthesis of Hydrogen Peroxide

Abstract

Photocatalytic H2O2 production by conversion of O2 in aqueous solution is often challenged by the use of sacrificial agents, the separation of powdery photocatalysts, solution, and contaminants, and low activity of photocatalyst. Herein, a membrane of covalent furan‐benzimidazole‐linked polymer (Furan‐BILP) with both O‐ and N‐containing heterocycles bonded via OCCN is reported for the first time as a photocatalyst to harvest clean H2O2 in pure water with high‐performance. A coordination‐polymer hard template strategy is developed to produce Furan‐BILP hollow microfibers that can be further assembled into membranes with desired sizes. The resultant Furan‐BILP membrane directly delivers clean H2O2 solution as the product with a high H2O2 production rate of 2200 µmol g−1 h−1 in pure water. Density functional theory calculations and experiment results indicate that the C atom from Furan ring on the linkage binds to the adsorbed OOH*, the H atom of OOH* forms a hydrogen bond with the N atom in the benzimidazole ring, thus the intermediate six‐membered ring structure stabilizes the OOH* and favors 2e‐ORR. The strategy using both molecular engineering to tune the electronic structure and macrostructural engineering to shape the morphology may be applied to design other coordination organic polymer photocatalysts with further improved performance.

The synergy between a benzoselenadiazole covalent organic framework and TEMPO for selective photocatalytic aerobic oxidation of organic sulfides

“…Typically, heterocycles are advantageous in synthesizing organic semiconductor materials due to their inherent characteristics. 26,27 As a photoactive electron-deficient heterocycle, benzoselenadiazole is attractive for integration into photoactive semiconductors as it could present remarkable photophysical and adjustable optoelectronic characteristics. 28,29 To date, benzoselenadiazole-based materials have been widely explored in organic photovoltaic devices to improve intramolecular electron transfer.…”

Boosting C3H6 Epoxidation via Tandem Photocatalytic H2O2 Production over Nitrogen-Vacancy Carbon Nitride

“…Compared to CN-Air, the emission peaks of CN-Ar exhibited strongly weakened intensity, suggesting greatly suppressed recombination of the photogenerated electron–hole pairs. , The transient photocurrent response curve of the sample can demonstrate its charge separation ability (Figure b). The transient photocurrent density of CN-Ar was significantly higher than that of CN-Air, indicating more efficient charge separation. , Electrochemical impedance spectroscopy (EIS) was used to evaluate the conductivity and interfacial charge transfer ability of the sample (Figure c). The smaller semicircle in the Nyquist plot compared indicated an increased interfacial charge transfer rate in CN-Ar .…”

“…The transient photocurrent density of CN-Ar was significantly higher than that of CN-Air, indicating more efficient charge separation. 49,50 Electrochemical impedance spectroscopy (EIS) was used to evaluate the conductivity and interfacial charge transfer ability of the sample (Figure 3c). The smaller semicircle in the Nyquist plot compared indicated an increased interfacial charge transfer rate in CN-Ar.…”

Porous covalent organic frameworks in photocatalytic ROS-mediated processes

“…Similarly, amorphous polymeric microfibers were developed by the joint collaboration of Kong, Wei and Yu groups. 154 A combination of the hard template strategy, followed by its etching away, was developed to produce furan-benzimidazole-linked polymer hollow microfibers, bearing both O- and N-based functionalities (Fig. 15).…”