混配体构筑的金属-有机框架及其水蒸气吸附性能研究

Water Vapour Adsorption Performance of Metal-Organic Framework Constructed by Mixed Ligands

采用4,4',4"-三羧基三苯胺和吡嗪作为混合配体,通过溶剂热法成功合成了一例多孔镍金属-有机框架(MOF)。对所得MOF的结构、形貌、相纯度和孔隙性质进行了详细表征,并考察了其吸附水蒸气的性能。测试结果显示,25℃条件下该MOF的水蒸气等温吸附曲线呈现S型,突跃起点的相对压力P/P 0为0.37,吸附量在P/P 0=0.4时达到0.41 g/g,脱附曲线与吸附曲线之间未见明显回滞现象。通过静电纺丝技术,将MOF粉末制备成膜,实际环境下的吸附测试结果显示,该MOF在40%相对湿度(21.5℃)下的水吸附量为0.40 g/g,且在75℃或阳光照射下短时间内可完成吸附-脱附循环。经过10次水吸附-解吸循环后,该材料能够保持初始的吸水性能。

A porous nickel metal-organic framework(MOF)was synthesized using 4,4',4"-tricarbonyl triphenylamine and pyrazine as mixed ligands via solvothermal method.The structure,morphology,phase purity,and porosity of the obtained MOF were characterized,and its water vapor adsorption performance was investigated.The adsorption-desorption experiments indicated that the isothermal(25℃)water vapor adsorption curve of the MOF exhibited an S shape,with a sharp onset at a relative pressure P/P 0 of 0.37,and an adsorption capacity of 0.41 g/g at P/P 0=0.4.There was no significant hysteresis between the desorption and adsorption curves.By employing electrospinning technology,the MOF was fabricated into a membrane,and adsorption tests under simulated actual environmental conditions showed that the MOF had a water adsorption capacity of 0.40 g/g at 40%relative humidity(21.5℃),and could complete adsorption-desorption cycles in a short time under 75℃heating or sunlight exposure.The material maintained its initial water absorption performance after 10 cycles of water adsorption-desorption.