Contrary to the popular opinion, it has been found that metallic Ti powder can be directly utilized as dopant precursor to prepare catalytically enhanced NaAlH4 through mechanical milling. As a novel method for prepar...Contrary to the popular opinion, it has been found that metallic Ti powder can be directly utilized as dopant precursor to prepare catalytically enhanced NaAlH4 through mechanical milling. As a novel method for preparation of catalytically enhanced NaAlH4, direct metallic Ti-doping possesses practical advantage over the state-of-the-art doping technology: elimination of the inactive by-products and the gas impurities that are highly detrimental to fuel cell operation. A systematic investigation along this new approach was performed under various preparation conditions, including different starting materials, milling atmosphere and milling time. The materials thus prepared under different conditions were found to share some common features, while at the meantime, differ significantly from each other on hydrogen storage performance. A comprehensive understanding of these results provides valuable insight into a series of fundamental questions in catalytically enhanced Ti-NaAlH4 system.展开更多
Zn/Sn/Cu （CZT） stacks were prepared by RF magnetron sputtering. The stacks were pretreated at different tem- peratures （200℃, 300 ℃, 350 ℃, and 400 ℃） for 0.5 h and then followed by sulfurization at 500℃ for ...Zn/Sn/Cu （CZT） stacks were prepared by RF magnetron sputtering. The stacks were pretreated at different tem- peratures （200℃, 300 ℃, 350 ℃, and 400 ℃） for 0.5 h and then followed by sulfurization at 500℃ for 2 h. Then, the structures, morphologies, and optical properties of the as-obtained Cu2ZnSnS4 （CZTS） films were studied by x-ray diffraction （XRD）, Raman spectroscopy, UV-Vis-NIR, scanning electron microscope （SEM）, and energy-dispersive x-ray spectroscopy （EDX）. The XRD and Raman spectroscopy results indicated that the sample pretreated at 350℃ had no secondary phase and good crystallization. At the same time, SEM confirmed that it had large and dense grains. According to the UV-Vis-NIR spectrum, the sample had an absorption coefficient larger than 10^4 cm-1 in the visible light range and a band gap close to 1.5 eV.展开更多
基金National Key Research and Development Program（2017YFB0902302）National Natural Science Foundation of China（51477165）Fundamental Research Funds for the Central Universities（2017RC009）
基金This work was financial by supported by Hundred Talents Project of Chinese Academy of Sciences and the National Natural Science Foundation of China (No.50571099).
文摘Contrary to the popular opinion, it has been found that metallic Ti powder can be directly utilized as dopant precursor to prepare catalytically enhanced NaAlH4 through mechanical milling. As a novel method for preparation of catalytically enhanced NaAlH4, direct metallic Ti-doping possesses practical advantage over the state-of-the-art doping technology: elimination of the inactive by-products and the gas impurities that are highly detrimental to fuel cell operation. A systematic investigation along this new approach was performed under various preparation conditions, including different starting materials, milling atmosphere and milling time. The materials thus prepared under different conditions were found to share some common features, while at the meantime, differ significantly from each other on hydrogen storage performance. A comprehensive understanding of these results provides valuable insight into a series of fundamental questions in catalytically enhanced Ti-NaAlH4 system.
基金supported by Funding for Outstanding Doctoral Dissertation in NUAA,China(Grant No.BCXJ13-12)the Jiangsu Innovation Program for Graduate Education,China(Grant No.CXLX13 150)+2 种基金the Fundamental Research Funds for the Central Universities,China(Grant No.61176062)the Science and Technology Supporting Project of Jiangsu Province,China(Grant No.BE2012103)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China
文摘Zn/Sn/Cu （CZT） stacks were prepared by RF magnetron sputtering. The stacks were pretreated at different tem- peratures （200℃, 300 ℃, 350 ℃, and 400 ℃） for 0.5 h and then followed by sulfurization at 500℃ for 2 h. Then, the structures, morphologies, and optical properties of the as-obtained Cu2ZnSnS4 （CZTS） films were studied by x-ray diffraction （XRD）, Raman spectroscopy, UV-Vis-NIR, scanning electron microscope （SEM）, and energy-dispersive x-ray spectroscopy （EDX）. The XRD and Raman spectroscopy results indicated that the sample pretreated at 350℃ had no secondary phase and good crystallization. At the same time, SEM confirmed that it had large and dense grains. According to the UV-Vis-NIR spectrum, the sample had an absorption coefficient larger than 10^4 cm-1 in the visible light range and a band gap close to 1.5 eV.
