原位蒸汽辅助法用于一步制备多级孔Cu-BTC

In situ steam-assisted method for one-step synthesis of hierarchically porous Cu-BTC

金属有机骨架材料(MOF)因其比表面积大、孔隙率高、结构高度可调等优势在气体吸附分离、催化、传感及生物医学等领域展现出巨大的应用潜力。但大多数MOF的孔结构在微孔范围,狭窄的孔隙环境限制了其应用过程中的传质扩散以及活性位点释放,在微孔MOF结构的基础上进行多级孔的构建则可以解决这一问题。为实现经典Cu-BTC结构上的多级孔构筑,基于原位蒸汽辅助合成加刻蚀过程开发了一步制备多级孔Cu-BTC的新方法。通过绿色刻蚀剂乙酸用量、蒸汽辅助时间的调节,获得了孔径范围可调的多级孔Cu-BTC。由于多级孔结构对传质过程和活性位点的提升作用,该材料在CO_(2)电还原实验中展现出优秀的转化效率,最高乙烯的选择性可提升157%。通过蒸汽辅助耦合材料制备和刻蚀过程使得多级孔MOF的一步制备成为了可能,其具有的减少反应物用量和反应步骤的特点将进一步推动多级孔MOF在实际应用中的发展。

Metal-organic framework(MOF)have shown great application potential in gas adsorption separation,catalysis,sensing and biomedicine due to their advantages such as large specific surface area,high porosity and highly adjustable structure.However,the pore structure of most MOF falls within the micropore range,and the narrow pore environment limits mass transfer diffusion and active site release during their application.Constructing hierarchical pores based on the microporous MOF structure can address this issue.To achieve hierarchically porous construction within the classic Cu-BTC structure,a novel single-step method combining in situ steam-assisted synthesis and etching was devised.Fine-tuning parameters such as the quantity of eco-friendly etchant acetic acid and steam assist duration yielded hierarchically porous Cu-BTC with customizable pore size ranges.Capitalizing on the enhanced mass transfer and active site accessibility conferred by the hierarchical pore architecture,the material demonstrated outstanding conversion efficiency in CO_(2) electroreduction experiments,culminating in a remarkable 157%increase in ethylene selectivity.Integrating material preparation and etching procedures through steam-assisted techniques enables streamlined fabrication of hierarchical porous MOF in a single step.This approach not only reduces reactant consumption and simplifies reaction steps but also propels the advancement of hierarchical porous MOF in practical applications.