改性氮化碳光催化剂在生物质氧化反应中的应用

利用氮化碳光催化剂催化生物质选择性转化,不仅扩展了非金属催化剂的应用领域,而且能够缓解化工产品过度依赖于化石能源的现状.2,5-二甲酰基呋喃是生产多种化工产品的关键中间体,本研究将均苯四甲酸二酐引入氮化碳骨架,并利用H2O2进行处理,制备了含有氮羟基的改性氮化碳光催化剂,并探究其在可见光激发下将生物质平台分子5-羟甲基...

Selective Oxidation of Biomass over Modified Carbon Nitride Photocatalysts

Using carbon nitride photocatalysts to catalyze the selective conversion of biomass platform molecules could not only expand the application fields of non-metallic catalysts but also alleviate the dependence on fossil energy in chemical manufacturing.2,5-diformylfuran is an indispensable intermediate for the production of value-added chemicals.In this study,pyromellitic dianhydride and melem were used as the precursors.The pyromellitic dianhydride monomer was incorporated into the carbon nitride skeleton by high-temperature heat-treatment,and the catalysts were further treated with H₂O₂.Finally non-metallic carbon nitride photocatalysts containing nitrogen hydroxyl groups were prepared.Moreover,its performance in the selective oxidation of 5-hydroxymethylfurfural into2,5-diformylfuran under visible light excitation was investigated.The results showed that H₂O₂-treated samples could generate nitroxide radicals under light irradiation,resulting in the selective oxidation of hydroxyl groups on the side chains of 5-hydroxymethylfurfural molecules into aldehyde groups,avoiding undesired side-reactions (ring-opening,mineralization reactions,etc.) caused by various reactive oxygen species that may be generated in aqueous solutions.In particular,under the excitation of an LED light source with a specific wavelength (400 nm),when the ratio of melem to PMDA precursor was 1:2,the selectivity of 2,5-diformylfuran over the photocatalyst could reach 96.2%.