摘要
生物质作为一种可再生的有机碳源,可满足人类对能源和化学品的巨大需求。其中,5-羟甲基糠醛(HMF)是最具应用潜力的生物质衍生平台分子之一,其氧化产物2,5-呋喃二甲酸(FDCA)有望替代对苯二甲酸(PTA)用于合成生物基降解塑料。由于反应条件温和、速率快和选择性高,电催化氧化HMF已成为制备FDCA非常有前景的绿色方法。此外,阳极电氧化HMF反应的理论电位(HMFOR,0.3 V vs.RHE)远低于析氧反应(OER,1.23 V vs.RHE),将其与阴极析氢反应(HER)耦合,有望在生产高附加值FDCA的同时降低产氢电位。然而,构建高效稳定的双功能催化剂用于HMFOR辅助制氢仍然具有挑战性。本文通过水热和高温煅烧的方法在泡沫镍上生长Co掺杂的Ni-Mo-O多孔纳米棒(Co-NiMoO/NF)用于HMFOR(E10/100=1.31/1.37 V vs.RHE)和HER(E−10/−100=−35/−123 mV vs.RHE),均表现出良好的活性和稳定性。对于HMFOR,Co-NiMoO/NF可以在1.36 V vs.RHE的恒电位下连续运行40个循环并保持较高的FDCA选择性(~99.2%)和法拉第效率(~95.7%)。对于HER,Co-NiMoO/NF可以在−200 mA∙cm^(−2)的电流密度下稳定运行50 h。作为双功能电极用于全HMF分解时,仅需1.48 V可达到50 mA∙cm^(−2),较全水解降低了290 mV,证明了Co-NiMoO/NF电氧化HMF辅助制氢大幅降低能耗的可行性。特别是,双电极体系能在1.45 V恒电位的驱动下,高效稳定地工作10个循环,并保持较高的FDCA选择性(~97.6%),表现出较好的应用潜力。Co-NiMoO/NF的良好催化性能可归因于Co的引入优化了Ni-Mo-O的电子结构和对反应物的吸附行为,从而提高了催化剂的本征活性和稳定性。同时,多孔纳米棒有助于底物分子和气泡在其表面的传输和脱附,进而提高了HMFOR/HER的反应动力学。这项工作有望为HMFOR和HER的高效稳定双功能催化剂的设计提供有益见解。
Fossil fuel depletion and environmental deterioration have created an urgent need to develop renewable and clean energy.Biomass,a sustainable organic carbon source,can meet the huge demand for energy and chemicals.Among them,5-hydroxymethylfurfural(HMF)is an important biomass-derived platform molecule,which can be converted into various high-value chemicals.One of its oxidation products,2,5-furandicarboxylic acid(FDCA),is expected to replace terephthalic acid as a raw material for the synthesis of bio-based degradable plastics.The electrooxidation of HMF emerges as a promising green route for preparing FDCA due to its advantages of mild conditions,fast reaction rate,and high selectivity.The theoretical potential of the HMF electrooxidation reaction(HMFOR,0.3 V vs.reversible hydrogen electrode,RHE)is also lower than that of the oxygen evolution reaction(OER,1.23 V vs.RHE).Coupling anodic HMFOR with cathodic hydrogen evolution reaction(HER)is expected to simultaneously produce valuable FDCA and reduce the cell voltage of hydrogen(H2)evolution.However,the construction of efficient and stable bifunctional catalysts for HMFOR-assisted H2 production is still challenging.In this study,Co-doped Ni-Mo-O porous nanorods grown on a nickel foam(Co-NiMoO/NF)is prepared by simple hydrothermal and calcination methods for both HMFOR and HER.Results of electrocatalytic studies indicate that Co-NiMoO/NF exhibits enhanced performance for HMFOR(E10/100=1.31/1.37 V vs.RHE)and HER(E−10/−100=−35/−123 mV vs.RHE)and shows durable HMFOR/HER stability.In particular,Co-NiMoO/NF maintains high FDCA selectivity(~99.2%)and Faradaic efficiency(~95.7%)for 40 successive cycles at 1.36 V vs.RHE for HMFOR.Conversely,Co-NiMoO/NF maintains stable operation at−200 mA∙cm^(−2) for 50 h with no significant activity attenuation for HER.When coupled as a bifunctional electrode for overall HMF splitting,Co-NiMoO/NF reaches an electric flux of 50 mA∙cm^(−2) at 1.48 V,which is 290 mV lower than that of the overall water splitting.This confirms that the HMFOR-assisted H2 production over Co-NiMoO/NF significantly reduces the energy consumption.Moreover,the two-electrode system maintains good FDCA selectivity(97.6%)for 10 cycles at 1.45 V,implying good stability of HMFOR-assisted H2 evolution.The remarkable catalytic performance of Co-NiMoO/NF could be due to the introduction of Co,which optimizes the electronic structure of Ni-Mo-O and adsorption behaviors of the reactants,thereby enhancing the intrinsic activity and stability of the catalyst.Meanwhile,the porous nanorod structure enhanced the mass transport of substrates and desorption of bubbles,thereby elevating the HMFOR/HER kinetics.This study provides useful insights for designing efficient and durable bifunctional catalysts for HMFOR and HER.
作者
郑书逸
吴佳
王可
胡梦晨
文欢
尹诗斌
Shuyi Zheng;Jia Wu;Ke Wang;Mengchen Hu;Huan Wen;Shibin Yin(Guangxi Key Laboratory of Electrochemical Energy Materials,College of Chemistry and Chemical Engineering,Guangxi University,Nanning 530004,China.)
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2023年第12期113-123,共11页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(22162004)
广西自然科学基金(2022JJD120011)资助项目。
关键词
5-羟甲基糠醛氧化反应
析氢反应
催化剂
多孔结构
电子结构
5-Hydroxymethylfurfural oxidation reaction
Hydrogen evolution reaction
Catalyst
Porous structure
Electronic structure
