Qin Qizhen, Li Tan, Sun Xuehao, Pei An, Jia Yanyan, He Hongpeng, Gao Fan, Wang Peng, Wu Qiqi, Liu Renfeng, Dai Sheng, Lin Haixin, Zhang Qingfeng, Zhao Yun, Chen Guangxu
School of Environment and Energy, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, South China University of Technology, Guangzhou 510006, China.
Faculty of Chemical Engineering, Kunming University of Science and Technology, Yunnan 650500, China.
Nano Lett. 2024 Dec 25;24(51):16351-16359. doi: 10.1021/acs.nanolett.4c04786. Epub 2024 Dec 11.
Direct oxidation of 5-hydroxymethylfurfural (HMF) to 5-hydroxymethyl-2-furancarboxylic acid (HMFCA), crucial for medical supply production, is hindered by overoxidation. We synthesized gold nanomaterials with distinct single-crystal facets, {111} in octahedra (OC), {100} in nanocubes (NCs), and {110} in rhombic dodecahedra (RD), to investigate the facet-dependent HMF oxidation. The Au RD achieved the spontaneous oxidation of HMF to HMFCA with stoichiometric hydrogen production, maintaining 95% carbon balance, 91% yield, and 98% selectivity. In contrast, Au OC and NCs were inert. The superior performance is due to the absence of a C-H activation energy barrier on the Au(110) facet. Furthermore, gas chromatography and isotope experiments supported that the intermediate is oxidized to produce H via H transfer, rather than HO via H transfer. Oxygen was essential for scavenging electrons, thereby closing the reaction loop. The Au RD exhibited remarkable stability, operating for 240 h without performance degradation, indicating its potential for efficient HMFCA production.
5-羟甲基糠醛（HMF）直接氧化为5-羟甲基-2-呋喃甲酸（HMFCA）对医疗用品生产至关重要，但过氧化会阻碍这一过程。我们合成了具有不同单晶面的金纳米材料，八面体（OC）中的{111}面、纳米立方体（NCs）中的{100}面和菱形十二面体（RD）中的{110}面，以研究面依赖的HMF氧化。金RD实现了HMF自发氧化为HMFCA并按化学计量产生氢气，保持了95%的碳平衡、91%的产率和98%的选择性。相比之下，金OC和NCs则呈惰性。优异的性能归因于Au(110)面上不存在C-H活化能垒。此外，气相色谱和同位素实验表明，中间体通过H转移被氧化生成H，而不是通过H转移生成HO。氧气对于清除电子至关重要，从而闭合反应循环。金RD表现出显著的稳定性，运行240小时性能无下降，表明其在高效生产HMFCA方面的潜力。
