[发明专利]一种气相沉积法制备纳米多孔镁的方法

说明书

本发明提供一种气相沉积法制备纳米多孔镁的方法，属于金属纳米材料制备技术领域。该方法以工业用镁粉作为原料，在低真空、辅助气体下，加热到一定温度进行蒸发，然后在较低温度的不锈钢网基底上沉积，最终得到羽毛状纳米多孔镁。制备得到的羽毛状纳米多孔镁由羽毛状纳米结构与多级孔隙构成。其中，孔隙有孔径为3.3~9.4μm的微米孔和孔径为385nm的纳米孔两种。该方法具有工艺简单，制备时间短，成本低廉，收得率高等优点。

技术领域

本发明涉及金属纳米材料制备技术领域，特别是指一种气相沉积法制备纳米多孔镁的方法。

背景技术

镁因其极高的可逆储氢量(7.6 wt.%)，较低的密度，丰富的储量和低廉的价格而在储氢领域有着巨大的潜在应用价值。但是其极差的吸放氢速度和较高的吸放氢温度都严重阻碍了其实际应用。而纳米化是一种极好的提高镁储氢性能的方法。相比块体镁，纳米镁保留了其高可逆储氢量，同时又具有极大地提高了吸放氢速度（ZALUSKA A, ZALUSKI L,STRÖM–OLSEN J O. Nanocrystalline magnesium for hydrogen storage[J]. Journalof Alloys and Compounds, 1999, 288(1–2): 217–225；HUOT J, LIANG G, BOILY S, etal. Structural study and hydrogen sorption kinetics of ball-milled magnesiumhydride[J]. Journal of Alloys and Compounds, 1999, 293–295: 495–500；ZHANG X,YANG R, YANG J, et al. Synthesis of magnesium nanoparticles with superiorhydrogen storage properties by acetylene plasma metal reaction[J].International Journal of Hydrogen Energy, 2011, 36(8): 4967–4975； NORBERG NS, ARTHUR T S, FREDRICK S J, et al. Size-dependent hydrogen storageproperties of Mg nanocrystals prepared from solution[J]. Journal of theAmerican Chemical Society, 2011, 133(28): 10679–10681；PASQUINI L, BRIGHI M,MONTONE A, et al. Magnesium nanoparticles for hydrogen storage: structure,kinetics and thermodynamics[J]. IOP Conference Series: Materials Science andEngineering, 2012, 38(1): 012001；LIU W, AGUEY-ZINSOU K-F. Size effects andhydrogen storage properties of Mg nanoparticles synthesised by an electrolessreduction method[J]. Journal of Materials Chemistry A, 2014, 2(25): 9718–9726.），并在一定程度上降低了吸放氢温度（AGUEY-ZINSOU K-F, ARES-FERNÁNDEZ J-R.Synthesis of colloidal magnesium: a near room temperature store for hydrogen[J]. Chemistry of Materials, 2008, 20(2): 376–378.）。但是纳米镁在应用过程中存在不易控制及团聚长大的问题（ZALUSKA A, ZALUSKI L, STRÖM–OLSEN J O.Nanocrystalline magnesium for hydrogen storage[J]. Journal of Alloys andCompounds, 1999, 288(1–2): 217–225；HUOT J, LIANG G, BOILY S, et al.Structural study and hydrogen sorption kinetics of ball-milled magnesiumhydride[J]. Journal of Alloys and Compounds, 1999, 293–295: 495–500；NORBERG NS, ARTHUR T S, FREDRICK S J, et al. Size-dependent hydrogen storageproperties of Mg nanocrystals prepared from solution[J]. Journal of theAmerican Chemical Society, 2011, 133(28): 10679–10681；LIU Y, ZOU J, ZENG X,et al. Study on hydrogen storage properties of Mg nanoparticles confined incarbon aerogels[J]. International Journal of Hydrogen Energy, 2013, 38(13):5302–5308.），导致了储氢性能的下降。而纳米多孔镁具有独特的双连续“孔隙-韧带”结构，具有处支持的特点。