香榧壳生物炭/g-C3N4活化过硫酸盐的光催化性能

采用简便一步热聚合法制备高催化活性的生物炭/g-C₃N₄复合光催化剂，并在可见光下活化过硫酸盐（PS）应用于对-乙酰氨基酚（AAP）废水的降解研究.通过紫外-可见漫反射吸收光谱（UV-vis DRS）、光致发光光谱（PL）对该复合催化剂的光学性质进行了研究.结果表明，生物炭的引入使g-C₃N₄的可见光吸收边界从483nm增强至553nm，并且提高了光致电子-空穴对的分离效率.扫描电子显微镜（SEM）、X射线衍射光谱（XRD）、傅里叶变换红外光谱（FT-IR）及X射线光电子能谱（XPS）的表征结果显示生物炭的引入改善了g-C₃N₄的微结构.在反应体系中引入PS强化了AAP的去除效率，在可见光照射下其降解速率是未添加PS的8.9倍，表明该催化体系可有效活化PS产生更多高活性氧化物质.自由基捕获实验表明该催化系统可能存在·O₂^-、h⁺、·OH和·SO₄^-活性物种，复合材料性能的提升主要归因于生物炭作为电子受体，有效抑制了电子-空穴的复合.

Study on photocatalytic performance of cephalotaxus shell biochar/g-C3N4 activated persulfate

g-C₃N₄/biochar composite photocatalysts with high catalytic activity were prepared by a simple one-pot thermal polymerization method using cephalotaxus shell and melamine as raw materials, which was applied to activate peroxynitrite(PS) for the degradation of acetaminophen(AAP) wastewater under visible light. The optical properties of the composite catalyst were investigated by UV-vis diffuse reflectance absorption spectroscopy(UV-vis DRS) and photoluminescence spectroscopy(PL), which showed that the visible light absorption boundary of g-C₃N₄ was enhanced from 483 nm to 553 nm and improved the separation efficiency of photogenerated electron-hole pairs due to the introduction of biochar. The results of scanning electron microscopy(SEM), X-ray diffraction spectroscopy(XRD), Fourier transform infrared spectroscopy(FT-IR) and X-ray photoelectron spectroscopy(XPS) showed that the microstructure of g-C₃N₄ was improved by the introduction of biochar. The removal efficiency of AAP was enhanced by the introduction of persulfate into the reaction system. The results show that the degradation rate for AAP under visible light irradiation was 8.9 times higher than that without PS addition, indicating that the catalytic system can effectively activate PS to produce more highly reactive oxidants. The radical capture experiments showed the presence of ·O₂^-, h⁺, ·OH and ·SO₄^-reactive substances in the catalytic system. The improvement of composite material performance was attributed to the effective inhibition of electron-hole recombination by biochar as an electron acceptor.