基于抗生素废水体系构建NxP(N=Ni,Co)/g-C3N4复合材料光催化制氢兼协同降解性能研究

Energy shortage and environmental pollution are two major issues in the modern society. In this project, the combination strategy of various synthetic techniques such as solid-state, hydrothermal/solvothermal, electrochemical and molten-salt methods are used to construct NxP(N=Ni,Co)/g-C3N4 composite photocatalysts with large surface area, intense light absorption capacity and high charge carrier separation efficiency. This project is designed to apply these photocatalysts to antibiotic wastewater systems, thus realizing “win-win” purpose of the high-efficiency hydrogen generation and antibiotic degradation. We will adopt XRD, SEM, TEM, SAED, etc. characterization methods to investigate morphology, lattice plane, defect, and phase interface of photocatalyst. Combined with the XPS/UPS valence band spectra, transient state PL spectra, photocurrent response curve, electrochemical impedance spectra, and DFT theoretical calculation, etc. we will study the generation, separation, transfer, recombination behavior mechanisms of charge carriers. The thermodynamic/dynamic laws in the diffusion, adsorption and photocatalytic reaction processes are studied by means of thermodynamic/dynamic function formula and DFT theoretical calculation. The photocatalytic reaction mechanism and the synergistic effect of hydrogen production and antibiotics degradation are also investigated through the analysis of the intermediates, reactive intermediate and so on. As a result, we achieve systematic cognition for above basic scientific and technical problems, which will provide theoretical and experimental bases for the solar photocatalytic technique applied widely to gaining hydrogen energy accompanied with purifying organic wastewater.

能源短缺和环境污染是当今社会面临的两个重大问题，本课题提出采用固相法、水/溶剂热法、电化学法及熔盐法等相结合的策略构筑比表面积大、吸光能力强、载流子分离效率高的NxP(N=Ni, Co)/g-C3N4复合光催化剂，旨在将其应用于抗生素污水体系，实现高效光催化制氢兼降解抗生素的双赢。采用 XRD、SEM、TEM、SAED等表征手段研究光催化剂的形貌、晶面、缺陷及相界面等微观结构特征；结合 XPS/UPS价带谱、瞬态PL光谱、光电流响应曲线、电化学阻抗谱及DFT理论计算等研究光生载流子的产生、分离、传输、复合等行为机理；利用基本热/动力学函数关系式并结合DFT 理论计算研究扩散、吸附及光催化反应过程的热/动力学规律；通过分析中间产物、活性中间体等研究光催化反应机理及光催化制氢兼降解抗生素的协同效应；为太阳能光催化技术应用于有机废水体系获得氢能兼净化有机污染物的研究提供理论依据和实验基础。

随着经济和社会的快速发展，产生的能源短缺和环境污染问题已然成为我国面临的两个亟待解决的重大问题，因此开发绿色新能源具有重要意义。本项目采用固相法、水/溶剂热法、静电驱动自组装法与简单磷化技术相结合的策略制备了一系列吸光能力强、载流子分离效率高的NxP(N=Ni, Co)/g-C3N4等复合光催化剂。系统研究了光催化制氢性能、降解性能、稳定性及重复利用性，结果表明这些光催化剂实现了高效、稳定地分解水制氢和降解水中的抗生物污染物；利用 X射线衍射谱(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、透射电子显微(TEM)、选区电子衍射(SAED)及同步辐射等先进技术手段研究了光催化剂的组成、形貌、晶面、缺陷、价态、元素及相界面等微观结构特征；结合 XPS价带谱、稳(瞬)态荧光光谱、光电流响应曲线及电化学阻抗谱等研究了光生载流子的产生、分离、传输、复合等行为机理；揭示了复合光催化剂的微观结构与光催化性能之间的构效关系。本项目为太阳能光催化技术广泛应用于分解水产氢和降解水限量抗生素类污染物提供了可行的解决方案和技术支撑，为材料化学、能源化学及化学工程等学科交叉发展提供了有价值的理论基础和实践经验。