催化学报 ›› 2021, Vol. 42 ›› Issue (11): 2027-2037.DOI: 10.1016/S1872-2067(21)63828-7

• 论文 • 上一篇    下一篇

限域NiCo合金纳米颗粒高效催化生物质衍生物水相加氢脱氧

汪东东a,b, 龚万兵a,#(), 张继方a,b, 韩苗苗c,$(), 陈春a, 张云霞a, 汪国忠a, 张海民a, 赵惠军a,d,*()   

  1. a中国科学院合肥物质科学研究院固体所, 环境与能源纳米材料中心, 安徽合肥230031, 中国
    b中国科学技术大学, 安徽合肥230026, 中国
    c湖州师范学院, 浙江湖州313000, 中国
    d格里菲斯大学, 清洁环境与能源中心, 昆士兰, 澳大利亚
  • 收稿日期:2021-03-16 修回日期:2021-03-16 接受日期:2021-04-15 出版日期:2021-11-18 发布日期:2021-06-08
  • 通讯作者: 龚万兵,韩苗苗,赵惠军
  • 基金资助:
    国家自然科学基金(51902311);国家自然科学基金(51871209);国家自然科学基金(61804154)

Encapsulated Ni-Co alloy nanoparticles as efficient catalyst for hydrodeoxygenation of biomass derivatives in water

Dongdong Wanga,b, Wanbing Gonga,#(), Jifang Zhanga,b, Miaomiao Hanc,$(), Chun Chena, Yunxia Zhanga, Guozhong Wanga, Haimin Zhanga, Huijun Zhaoa,d,*()   

  1. aKey Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, CAS Centre for Excellence in Nanoscience, Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China
    bUniversity of Science and Technology of China, Hefei 230026, Anhui, China
    cSchool of Science, Huzhou University, Huzhou 313000, Zhejiang, China
    dCentre for Clean Environment and Energy, Gold Coast Campus, Griffith University, Queensland 4222, Australia
  • Received:2021-03-16 Revised:2021-03-16 Accepted:2021-04-15 Online:2021-11-18 Published:2021-06-08
  • Contact: Wanbing Gong,Miaomiao Han,Huijun Zhao
  • About author:$E-mail:Tel: +86-551-65591263; Fax: +86-551-65591434; E-mail: mmhan@zjhu.edu.cn
    #Tel: +86-551-65591263; Fax: +86-551-65591434; E-mail: wbgong@issp.ac.cn;
    *Tel: +86-551-65591263; Fax: +86-551-65591434; E-mail: h.zhao@griffith.edu.au;
  • Supported by:
    National Natural Science Foundation of China(51902311);National Natural Science Foundation of China(51871209);National Natural Science Foundation of China(61804154)

摘要:

将储量丰富的生物质及其衍生物转化为具有高附加值的燃料和化学品被认为是一种有前景的绿色途径, 可以极大地减少人们对传统化石资源的依赖. 作为木质纤维素热解的直接产物和生物油升级的模型化合物, 香草醛可以通过加氢脱氧(HDO)过程选择性地转化为2-甲氧基-4-甲基苯酚(MMP). MMP是一种有价值的化学品, 常用于香料和药物等重要中间体的合成. 在过去十年里, 大量的金属催化剂被用来催化香草醛HDO转化为MMP. 其中, 贵金属(Pt, Pd, Ru和Au)虽然活性高, 但是其储量低、价格昂贵, 不利于工业化应用; 而非贵金属(Fe, Co, Ni和Cu)的催化活性普遍较低, 需要苛刻的反应条件来提高转化效率和选择性. 此外, 这类HDO反应大都在有机溶剂中进行, 容易造成环境污染. 因此, 开发高效、稳定的非贵金属催化剂用于水相HDO反应是一个巨大的挑战.
一般来说, 合金纳米颗粒(NPs)具有强烈的协同效应, 能产生良好的配位结构和电子环境, 从而显著提升催化活性和选择性. 基于此, 本文首次采用了一种简单可控的合成方法来制备三聚氰胺海绵负载的氮掺杂碳纳米管(N-CNTs)限域的Ni-Co合金NPs(NiCo@N-CNTs/CMF)催化剂. 该催化剂具有优异的HDO性能, 在2 MPa H2, 120 ºC反应6 h条件下, 能在水相中将生物质衍生的香草醛高效转化为MMP, 转化率和选择性均达到100%. 相比于单金属的Ni@N-CNTs/CMF和Co@N-CNTs/CMF催化剂, 香草醛转化率和MMP选择性都有大幅度的提高. 而且, 在温和的反应条件下, 该催化剂对香草醛衍生物和其他芳香醛类化合物同样表现出优异的HDO性能, 拥有100%的转化率以及较高的MMP选择性(91.5%~100%). XPS结果表明, Ni-Co形成合金后发生了电子结构的偏移, 即Co原子可以从邻近的Ni原子处得到电子, 提高Co电子云密度, 从而促进对香草醛中C=O键的吸附. DFT计算结果表明, 相比于单金属的Ni和Co, Ni-Co合金化后能显著提高对C=O键的选择性吸附和活化. 同时, H2解离后形成的活性H*物种在Ni-Co合金NPs表面更容易脱附并参与催化反应. 因此, NiCo@N-CNTs/CMF催化剂优异的HDO性能主要是由于Ni-Co合金NPs的协同作用大大促进了其对C=O键的选择性吸附和活化, 以及活化氢物种的脱附. 本文为设计和制备高效的非贵金属催化剂应用于水相的HDO反应提供了一个新策略.

关键词: Ni-Co合金纳米颗粒, 碳纳米管, 加氢脱氧, 生物质衍生物, 水溶剂

Abstract:

Catalytic hydrodeoxygenation (HDO) is one of the most promising strategies to transform oxygen-rich biomass derivatives into high value-added chemicals and fuels, but highly challenging due to the lack of highly efficient nonprecious metal catalysts. Herein, we report for the first time of a facile synthetic approach to controllably fabricate well-defined Ni-Co alloy NPs confined on the tip of N-CNTs as HDO catalyst. The resultant Ni-Co alloy catalyst possesses outstanding HDO performance towards biomass-derived vanillin into 2-methoxy-4-methylphenol in water with 100% conversion efficiency and selectivity under mild reaction conditions, surpassing the reported high performance nonprecious HDO catalysts. Impressively, our experimental results also unveil that the Ni-Co alloy catalyst can be generically applied to catalyze HDO of vanillin derivatives and other aromatic aldehydes in water with 100% conversion efficiency and over 90% selectivity. Importantly, our DFT calculations and experimental results confirm that the achieved outstanding HDO catalytic performance is due to the greatly promoted selective adsorption and activation of C=O, and desorption of the activated hydrogen species by the synergism of the alloyed Ni-Co NPs. The findings of this work affords a new strategy to design and develop efficient transition metal-based catalysts for HDO reactions in water.

Key words: Ni-Co alloy nanoparticles, Carbon nanotubes, Hydrodeoxygenation, Biomass derivatives, H2O solvent