A Series of Inorganic Solid Nitrogen Sources for the Synthesis of Metal Nitride Clusterfullerenes: The Dependence of Production Yield on the Oxidation State of Nitrogen and Counter Ion

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• 作者：Fupin Liu ; Jian Guan ; Tao Wei ; Song Wang ; Mingzhi Jiao ; Shangfeng Yang
• 刊名：Inorganic Chemistry
• 出版年：2013
• 出版时间：April 1, 2013
• 年：2013
• 卷：52
• 期：7
• 页码：3814-3822
• 全文大小：549K
• 年卷期：v.52,no.7(April 1, 2013)
• ISSN：1520-510X

文摘

A series of nitrogen-containing inorganic solid compounds with variable oxidation states of nitrogen and counter ions have been successfully applied as new inorganic solid nitrogen sources toward the synthesis of Sc-based metal nitride clusterfullerenes (Sc-NCFs), including ammonium salts [(NH₄)_xH_3-xPO₄ (x = 0鈥?), (NH₄)₂SO₄, (NH₄)₂CO₃, NH₄X (X = F, Cl), NH₄SCN], thiocyanate (KSCN), nitrates (Cu(NO₃)₂, NaNO₃), and nitrite (NaNO₂). Among them, ammonium phosphates ((NH₄)_xH_3-xPO₄, x = 1鈥?) and ammonium thiocyanate (NH₄SCN) are revealed to behave as better nitrogen sources than others, and the highest yield of Sc-NCFs is achieved when NH₄SCN was used as a nitrogen source. The optimum molar ratio of Sc₂O₃:(NH₄)₃PO₄路3H₂O:C and Sc₂O₃:NH₄SCN:C has been determined to be 1:2:15 and 1:3:15, respectively. The thermal decomposition products of these 12 inorganic compounds have been discussed in order to understand their different performances toward the synthesis of Sc-NCFs, and accordingly the dependence of the production yield of Sc-NCFs on the oxidation state of nitrogen and counter ion is interpreted. The yield of Sc₃N@C₈₀ (I_h + D_5h) per gram Sc₂O₃ by using the N₂-based group of nitrogen sources (thiocyanate, nitrates, and nitrite) is overall much lower than those by using gaseous N₂ and NH₄SCN, indicating the strong dependence of the yield of Sc-NCFs on the oxidation state of nitrogen, which is attributed to the 鈥渋n-situ鈥?redox reaction taking place for the N₂-based group of nitrogen sources during discharging. For NH₃-based group of nitrogen sources (ammonium salts) which exhibits a (鈭?) oxidation states of nitrogen, their performance as nitrogen sources is found to be sensitively dependent on the anion, and this is understood by considering their difference on the thermal stability and/or decomposition rate. Contrarily, for the N₂-based group of nitrogen sources, the formation of Sc-NCFs is independent to both the oxidation state of nitrogen (+3 or +5) and the cation.