Li Xiang, Wang Yunyi, Wu Ting, Fang Guigan
Institute of Chemical Industry of Forest Products, Chinese Academy of Forestry, Key Lab. of Biomass Energy and Material, Jiangsu Province, Co-Innovation Center of Efficient Processing and Utilization of Forest Resource, Jiangsu Province, Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration, National Engineering Lab. for Biomass Chemical Utilization, Nanjing 210042, China.
Heilongjiang Provincial Key University Laboratory of Processing Agricultural Products, College of Food and Bioengineering, Qiqihar University, Qiqihar 161006, China.
J Colloid Interface Sci. 2024 Aug 15;668:658-665. doi: 10.1016/j.jcis.2024.04.192. Epub 2024 Apr 27.
The graphitic carbon nitride (g-CN) photocatalysis has emerged as a clean method for cleaving lignin-linked bonds due to its mild and sunlight-driven reaction conditions. The fast electron-hole pair complex of g-CN constrains its degradation efficiency, making the heterojunction construction a popular solution. The conventional methods of preparing g-CN heterojunctions by physical mixing destroy π-conjugations in g-CN, reducing the adsorption of lignin containing benzene rings. In this study, a novel indium oxide (InO) quantum dot-g-CN 0D/2D heterojunction was prepared through the high-temperature oxidation of pre-prepared indium-doped g-CN. The introduction of InO at the quantum dot level minimizes the interference with lignin adsorption capacity. The strong combination of the two (InO and g-CN) increases the intersection interface area, promoting the S-scheme transfer route of the photogenerated electrons. Consequently, this enhances the photoelectric conversion efficiency and carrier lifetime of the heterojunction, and inhibits the rapid recombination of photogenerated electron-hole pairs in g-CN. The proposed heterojunction was 3 times more efficient than g-CN alone for selective cleavage of lignin β-O-4 bonds after 2 h of sunlight irradiation. Combined with inhibitor experiments and gas chromatography-mass spectrometry analysis, this paper defines the reactive oxides and proposes a cleavage pathway for the lignin β-O-4 bonds in InO-g-CN heterojunction system.
石墨相氮化碳（g-CN）光催化因其温和且受阳光驱动的反应条件，已成为一种用于裂解木质素连接键的清洁方法。g-CN快速的电子-空穴对复合限制了其降解效率，使得异质结构建成为一种常用的解决方案。通过物理混合制备g-CN异质结的传统方法会破坏g-CN中的π共轭，降低对含苯环木质素的吸附。在本研究中，通过对预先制备的铟掺杂g-CN进行高温氧化，制备了一种新型的氧化铟（InO）量子点-g-CN 0D/2D异质结。在量子点水平引入InO可将对木质素吸附能力的干扰降至最低。两者（InO和g-CN）的强结合增加了交叉界面面积，促进了光生电子的S型转移途径。因此，这提高了异质结的光电转换效率和载流子寿命，并抑制了g-CN中光生电子-空穴对的快速复合。在阳光照射2小时后，所提出的异质结对木质素β-O-4键的选择性裂解效率比单独的g-CN高3倍。结合抑制剂实验和气相色谱-质谱分析，本文确定了反应性氧化物，并提出了InO-g-CN异质结体系中木质素β-O-4键的裂解途径。
