木糖选择性电催化氧化制备甲酸  

Selective electrooxidation of xylose to formic acid

作　　者：王宁 陈泽虹 彭新文 WANG Ning;CHEN Zehong;PENG Xinwen(State Key Laboratory of Pulp and Paper Engineering,School of Light Industry Science and Engineering,South China University of Technology,Guangzhou 510641,China)

机构地区：[1]华南理工大学轻工科学与工程学院,制浆造纸工程国家重点实验室,广州510641

出　　处：《林业工程学报》2025年第2期104-110,共7页Journal of Forestry Engineering

基　　金：国家重点研发计划(2023YFE0109600);国家万人计划青年拔尖人才支持计划(x2qsA4210090);国家自然科学基金(32201499);广州市重点研发计划(2023B03J1330)。

摘　　要：电解水是一种前景广阔的绿色制氢技术,但阳极析氧反应(OER)所需的理论电势较高,限制了电解水的制氢效率。将作为林木生物质资源和造纸废液主要成分之一的木糖选择性地电催化氧化以替代阳极OER反应制备化学品,有望能够提高林木生物质资源综合利用率与高值化。本研究以碳毡为基底,通过水热法原位生长制备了氢氧化镍[Ni(OH)_(2)@CF]和氢氧化钴[Co(OH)_(2)@CF]催化剂,并将其应用于电催化木糖氧化制甲酸,通过扫描电子显微镜、能量色散X射线光谱仪、X射线衍射、X射线光电子能谱、透射电子显微镜和电感耦合等离子体-光学发射光谱分析法等对催化剂的微观形貌、元素组成以及化学结构等进行表征和分析。结果表明,Co(OH)_(2)为纳米颗粒结构且负载量较低,而Ni(OH)_(2)以纳米片结构均匀负载在碳毡表面,高的负载量和纳米片结构可为木糖吸附和反应提供更多的活性位点,进而提高Ni(OH)_(2)@CF的电催化性能。与纯碳毡和Co(OH)_(2)@CF相比,Ni(OH)_(2)@CF具有最优的电催化木糖氧化活性,当电流密度达到100 mA/cm^(2)时所需电位仅为1.46 V(vs.RHE),与OER相比降低了180 mV。同时,Ni(OH)_(2)@CF电催化木糖氧化制甲酸产率和选择性可达53.49%和62.03%,法拉第效率为59.42%。Water electrolysis is a promising and prospective approach for producing green hydrogen and reducing fossil fuel use,thereby mitigating environmental pollution.Xylose,a component of forest biomass and pulping waste,is abundant,resourceful,low-cost,and renewable.Selective oxidation of xylose to high-value products and chemicals can enhance resource utilization,increase the value of forest biomass,and reduce fossil fuel consumption.However,the high theoretical potential of the oxygen evolution reaction(OER)at anode reaction limits the efficiency of hydrogen production through water electrolysis.Replacing the sluggish OER with the thermodynamically and kinetically favorable xylose electrooxidation reaction can improve hydrogen production efficiency while generating high-value products and chemicals.In this study,nickel hydroxide[Ni(OH)_(2)@CF]and cobalt hydroxide[Co(OH)_(2)@CF]were synthesized by hydrothermal process with carbon felt as framework.The morphology,elemental composition,and chemical structure of the catalysts were investigated using the scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDS),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),transmission electron microscopy(TEM)and inductively coupled plasma-optical emission spectrometry(ICP-OES).The catalysts were applied to convert xylose to formic acid by electrooxidation.The results showed that Ni(OH)_(2)was uniformly and abundantly grown on the surface of the carbon felt with a nanosheet structure,while small amount of Co(OH)_(2)nanoparticles was detected by SEM and ICP-OES.The catalysts of crystal structure and chemical structure were characterized and confirmed by XRD,HR-TEM and XPS.As shown in the electrochemical experiments and material characterization,the high loading,tested by ICP-OES,and nanosheet structure of Ni(OH)_(2)can provide more active sites for xylose adsorption and electrooxidation reaction,thus improving the xylose of electrooxidation performance and selectivity.Compared to the pure carbon felt and C

关 键 词：氢氧化镍 氢氧化钴 电催化 生物质 木糖氧化 

分 类 号：TS7[轻工技术与工程—制浆造纸工程]