非金属掺杂生物质多孔碳基材料的合成及对MgH_(2)储氢性能的研究  

Synthesis of non-metal-doped biomass porous carbon-based materials and their influence on hydrogen storage properties of MgH_(2)

作　　者：阎帅 宋静雅 游卓[1] 左逾 叶宏亮 张田力 Yan Shuai;Song Jingya;You Zhuo;Zuo Yu;Ye Hongliang;Zhang Tianli(Hunan Railway Professional Technology College,Zhuzhou 412001;Changsha Research Institute of Mining and Metallurgy Co.,Changsha 410083)

机构地区：[1]湖南铁道职业技术学院,株洲412001 [2]长沙矿冶研究院有限责任公司,长沙410083

出　　处：《化工新型材料》2024年第S01期122-127,共6页New Chemical Materials

基　　金：湖南省教育厅科学研究项目(22C1113);长沙市“揭榜挂帅”重大科技项目(kq2102004)。

摘　　要：氢化镁(MgH_(2))作为一种固态储氢材料,因其安全性高、储氢量大及镁资源丰富等优点,吸引了大量的学者对其进行研究。然而其稳定的热力学性能、较差的动力学性能及欠佳的循环稳定性导致其商业化道路受阻。采用一步溶剂热法和高温碳化法制备了以廉价生物质原料为基体的非金属磷掺杂碳基材料(P/BC),并通过进一步的高能球磨将其引入MgH_(2)储氢体系中,得到MgH_(2)@P/BC复合储氢体系。结果表明:P/BC降低了MgH_(2)晶粒的尺寸大小,且极大地提升了该复合储氢体系的储氢性能,使其在400℃下,10min内可释放约6%的氢气,同时该体系的放氢活化能相比纯MgH_(2)体系降低了16.77kJ/mol。P/BC材料较大的比表面积和优异的孔隙结构,增加了氢气的吸附速率并提供更多的活性位点,如表面缺陷和多相界面等。此外,P元素的掺杂可以调控碳基体的表面电子结构,与多孔碳共同形成了催化-限域效应,进而对复合储氢材料的吸放氢性能起到了积极的促进作用。Magnesium hydride(MgH_(2))has garnered significant scholarly attention as a solid hydrogen storage material owing to its notable advantages,such as high safety,ample hydrogen storage capacity and abundant magnesium resources.However,the commercialization of MgH_(2) is impeded by its stable thermodynamic properties,sluggish kinetic properties,and poor cyclic stability.A MgH_(2)@P/BC composite hydrogen storage system was obtained by introducing non-metallic phosphorus-doped biomass carbon-based material(P/BC),which was prepared using a one-step solvothermal method and high-temperature carbonization method from cheap biomass feedstock and then introduced into the MgH_(2) hydrogen storage system through high-energy ball milling.It was found that the addition of P/BC reduced the grain size of MgH_(2) and significantly enhanced the hydrogen storage performance of the composite hydrogen storage system.The composite system was capable of releasing approximately 6%hydrogen within 10 minutes at 400℃,and its activation energy was 16.77kJ/mol lower than that of the pure MgH_(2) system.The larger specific surface area and excellent pore structure of the P/BC material increased the adsorption rate of hydrogen and provided more active sites,such as surface defects and multiphase interfaces.In addition,the doping of P element could regulate the surface electronic structure of carbon matrix,and formed a catalytic-confinement effect with porous carbon,which played a positive role in promoting the hydrogen absorption and emission properties of the composite hydrogen storage materials.

关 键 词：储氢 氢化镁 生物质炭 催化效应 限域效应 

分 类 号：TB34[一般工业技术—材料科学与工程]