NiFe-MOF和氮氧自由基协同增强甾醇电催化氧化  

Enhanced Electrocatalytic Oxidation of Sterols using the Synergistic Effect of NiFe-MOF and Aminoxyl Radicals

作　　者：许银洁 李随勤 刘力豪 贺佳辉 李凯[1] 王梦欣 赵舒影 李纯 张峥斌 钟兴[1] 王建国[1] Yinjie Xu;Suiqin Li;Lihao Liu;Jiahui He;Kai Li;Mengxin Wang;Shuying Zhao;Chun Li;Zhengbin Zhang;Xing Zhong;Jianguo Wang(Institute of Industrial Catalysis,State Key Laboratory Breeding Base of Green-Chemical Synthesis Technology,College of Chemical Engineering,Zhejiang University of Technology,Hangzhou 310032,China;Research and Development Department,Zhejiang Xianju Junye Pharmaceutical Co.,Ltd.,Taizhou 317300,Zhejiang Province,China)

机构地区：[1]浙江工业大学化工学院工业催化研究所,绿色化学合成技术国家重点实验室,杭州310032 [2]浙江仙居君业药业有限公司研发部,浙江台州317300

出　　处：《物理化学学报》2024年第3期44-45,共2页Acta Physico-Chimica Sinica

基　　金：国家重点研发计划(2022YFA1504200,2021YFA1500903);浙江省自然科学基金(LR22B060003);国家自然科学基金(22078293,21625604,91934302,22141001)资助项目。

摘　　要：传统甾醇中间体氧化采用重金属铬作为氧化剂,存在毒性大和环境污染等问题。电催化氧化(ECO)以其高效、环保、可控的优点备受青睐,被认为是一种可替代传统工艺的方法。然而,目前ECO面临低电流密度和低时空产率的挑战。本研究采用一步溶剂热法在石墨毡上制备自支撑NiFe-MOF纳米片电催化剂,并耦合NiFe-MOF与氮氧自由基(4-乙酰氨-2,2,6,6-四甲基哌啶-1-氧)协同电催化策略以提高ECO性能。研究发现碱性电解液可重构NiFe-MOF催化剂,从而提高催化活性。此外,连续流动强化传质,成功实现以100 mA·cm^(-2)的大电流密度对19-羟基-4-雄甾烯-3,17-二酮(1a)的选择性电催化氧化,且选择性高达98%,时空产率可达15.88 kg·m^(-3)·h^(-1),是间歇电反应器的35倍。寿命测试发现经10次循环反应后,NiFe-MOF/ACT协同体系对ECO仍具有较高的转化率。通过增大NiFe-MOF面积,将其组装至连续流动式电反应器并进行ECO恒电流电解,可达到12.99 kg·m^(-3)·h^(-1)的时空产率。该工作提出一种NiFe-MOF/ACT协同电催化氧化策略,为实现甾醇选择性氧化提供新的见解。Conventional oxidation methods of sterol intermediates using the heavy metal chromium as an oxidant has critical drawbacks,such as high toxicity and environmental pollution.Electrocatalytic oxidation(ECO),on the other hand,is considered a promising alternative to conventional processes owing to its high efficiency,eco-friendliness,and controllability.However,ECO currently faces two major challenges:low current densities and reduced space-time yields.In this study,a single-step solvothermal method was employed to synthesize self-supported nickel-iron metal-organic framework(NiFe-MOF)nanosheet electrocatalysts on graphite felt.Various analytical techniques were employed to comprehensively characterize the synthesized NiFe-MOF,including scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD),Raman spectroscopy,and Brunauer-Emmett-Teller(BET)analysis Furthermore,we implemented a synergistic electrocatalytic strategy by combining the NiFe-MOF catalyst with aminoxyl radicals,i.e.,4-acetamido-2,2,6,6-tetramethyl-1-piperidine-N-oxyl(ACT),to enhance the performance of the ECO reaction.According to the results of structural characterization,the synthesized NiFe-MOF exhibited an amorphous nanosheet structure with a high specific surface area and microporosity.Moreover,we successfully achieved continuous flow with enhanced mass transfer during the electrocatalytic oxidation of 19-hydroxy-4-androstene-3,17-dione(1a)at a current density of 100 mA·cm^(-2).The optimal reaction conditions for the ECO reaction were as follows:100 mmol·L^(-1)concentration of 1a,10%(molar fraction)of ACT,a 1 mol·L^(-1)Na_(2)CO_(3)/acetonitrile electrolyte(6:4),room temperature,pH 12.5,and a flow rate of 225 mL·min-1.Under these conditions,the conversion and selectivity of the reaction reached outstanding levels of 99 and 98%,respectively.Moreover,the space-time yield was calculated to be as high as 15.88 kg·m^(-3)·h^(-1),with a remarkable 35-fold increase compared to that achieved in a batch reactor.The N

关 键 词：甾醇 电催化氧化 金属有机框架 氮氧自由基 协同作用 

分 类 号：O646[理学—物理化学]