Guanglu Xia,Jianhao Qiu,Dingliang Dai,Yong Tang,Zhonghao Wu,Jianfeng Yao
A covalent organic framework (COF) named TpPa-1 was co-modified by chlorine grafting and ZnIn2S4 integration for concurrent photocatalytic H2O2 generation and wastewater purification under visible light. The introduction of electron-withdrawing chlorine groups on TpPa-1 decreases the density of adjacent electron clouds, which promotes the charge carrier separation and the intimate combination with ZnIn2S4 by Cl–Zn/Cl–In bonds, providing an appreciably enhanced photocatalytic activity. Specifically, in pure water, the optimal ZnIn2S4/TpPa-Cl2 sample can achieve a H2O2 yield of 766 μmol L−1, which is 1.5, 2, 7.8 and 5 times those of ZnIn2S4/TpPa-1, TpPa-Cl2, ZnIn2S4 and TpPa-1, respectively. In the tetracycline solution, 95% of tetracycline was degraded and, concomitantly, H2O2 with a yield of 846 μmol L−1 was generated. It is found that H2O2 generation undergoes a two-step O2 reduction with ·O2− as the intermediate, while ·O2−, holes and ·OH are the active species in tetracycline degradation. Likewise, other common pollutants like o-nitrophenol, acid golden yellow and acid red in wastewater could also be effectively degraded along with the appreciable production of H2O2, which realizes the so-called wastewater valorization. This study could advance COF-based photocatalysts and provide a novel insight into wastewater treatment.
Electrocatalytic carbon dioxide reduction reaction (CO 2 RR) to formic acid is considered an economically viable avenue toward carbon neutrality. Indium-based catalysts have garnered considerable attention in CO 2 RR owing to their elevated hydrogen evolution reaction (HER) overpotential and eco-friendly characteristics. We have synthesized In 2 O 3 nanofibers rich in oxygen vacancies using the electrospinning technique. The resultant 500-In 2 O 3 exhibited superior performance in converting CO 2 RR to HCOOH, achieving an impressive formate Faradaic efficiency (FE) of 92.1% at a current density of −600 mA cm −2 . Moreover, it demonstrated remarkable stability, maintaining its performance over 100 h at a current density of −300 mA cm −2 under a neutral electrolyte. Density functional theory (DFT) calculations, in conjunction with spectroscopic characterizations, have revealed that a Cl-modified In catalyst exhibits a lowered energy barrier for the formation of *HCOOH, while simultaneously inhibiting the generation of *H, in contrast to its pristine In counterpart. Ultimately, we successfully engineered a dual-electrode system capable of simultaneously producing formate at both the cathode and the anode. At a current density of −100 mA cm −2 , our system achieves a reduction in energy consumption by 12.5% and a significant enhancement in electrical energy conversion efficiency by 39.9%.
Poly(vinyl pyrrolidone) (PVP) and stearoyl chloride (SC) double-grafted chitosan (PCS) nanoparticles (NPs) were prepared for paclitaxel (PTX) delivery. PTX could be effectively loaded into PCS NPs with encapsulation efficiency of 92.8%. PTX-loaded PCS NPs (PTX/PCS NPs), which possessed particle sizes of 144 nm and Zeta potentials of −7.5 mV, exhibited a sustained release behavior. In H-22 tumor bearing mice, significantly enhanced antitumor efficacies were achieved by PTX/PCS NPs with the tumor inhibition ratio (TIR) of 76.1% as compared with PTX injection. Furthermore, no signs of sub-acute toxicity were detected in healthy mice, indicating the safety of PCS NPs. Therefore, PCS NPs could be served as an effective and safe carrier for PTX delivery.