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低成本、高性能的钠离子电池有望成为代替锂离子电池的下一代核心器件.但是开发出高比容量、高倍率的钠离子电池负极材料依然是瓶颈.本文通过水热/溶剂热法制备了Co基前驱体,然后将其一步硫/磷热处理制得具有空心多孔结构的h-Co9S8/CoP/C纳米复合材料.通过X-射线粉末衍射(XRD)、拉曼光谱(Raman)、扫描电镜(SEM)、透射电镜(TEM)和X-射线光电子能谱(XPS)等表征以确定纳米复合物的物相以及形貌特征.当h-Co9S8/CoP/C作为钠离子电池负极材料时,该电极材料展示了高的比容量(561 mAh g-1@0.1 Ag-1)、较好的循环性能(可逆比容量200 mAh g-1@2 Ag-1)和倍率性能.h-Co9S8/CoP/C之所以显示出良好的储钠性能,主要得益于其空心多孔结构不仅提供更多的空间缓解钠在反复嵌入和脱出过程造成的体积膨胀效应,而且可以缩短离子/电荷扩散途径以加快反应动力学,此外,Co9S8、CoP和C独特的电子结构优势得以共同发挥. 相似文献
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通过水热法合成了一个由三连接的2,3-喹啉二甲酸桥联扭曲的Cd2+八面体形成的二维层状配位聚合物[Cd(QDA)]n(1)。该配合物发射出较强的蓝色荧光并具有很高的热稳定性和化学稳定性。更为重要的是,该配合物在乙醇分散体系中可快速识别痕量的2,4,6-三硝基苯酚和Fe3+离子,其对2,4,6-三硝基苯酚的淬灭常数(Ksv)和检测限(LOD)分别为6.61×104 L·mol-1和0.83 μmol·L-1,对Fe3+离子的淬灭常数和检测限分别为1.74×104 L·mol-1和2.70 μmol·L-1。 相似文献
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合成并通过单晶和粉末X射线衍射、元素分析、红外光谱、热失重以及荧光光谱技术表征了含有4-(1,2,4-三唑-1-基)苯酚(hptrz)配体的2个过渡金属配合物{[Ni(H_2O)_2(hptrz)_2(tp)]·2DMF}_n(1)和[Cu(hptrz)_2(SCN)_2]·2H_2O (2)(H_2tp为对苯二甲酸)。配合物1中八面体的Ni(Ⅱ)离子由tp~(2-)阴离子拓展形成线性的一维链状结构;而配合物2则呈现中心对称的单核结构。配合物中,中性的hptrz配体呈现端基配位模式,并通过形成O-H…O氢键相互作用将低维结构拓展为高维超分子网络。此外,配体内的电荷转移使这2个配合物均在紫外区发射出强的荧光发射峰。 相似文献
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Self-assembly reaction of 1,2,4,5-benzenetetracarboxylic acid(H_4 btc) with CuCl_2 in mixed N,N-dimethylformamide(DMF), methanol and aqueous solution at room temperature generated a 2D complex, [Cu(btc)_(0.5)(DMF)(H_2 O)]_n(1) which was further characterized by X-ray diffraction, IR spectrum, elemental analysis and TG-DTA experiments. The structure determination reveals that the fundamental unit of complex 1 contains one Cu(Ⅱ) ion, half a btc~(4–), one DMF molecule and one water molecule, forming a half paddlewheel-like building block [Cu_2(btc)(DMF)_2(H_2 O)_2] which is different from those previous Cu-btc(Ⅱ) polymers obtained either in water or other media without water. It crystallizes in monoclinic system, space group C2/c with a = 22.8209(14), b = 9.2244(6), c = 10.8876(7) ?, b = 117.5210(10)o, V = 2032.6(2) ?~3, Z = 2, C_8 H_(10) CuNO_6, M_r = 279.71, D_c = 1.828 g/cm~3, μ = 2.162 mm-1, F(000) = 1136, the final R = 0.0225 and wR = 0.0652 with I 2s(I). Furthermore, the thermal stability of complex 1 is observed to be dependent on the polymeric structure nature. And the luminescent measurements show that complex 1 produces strong emission at room temperature. 相似文献
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Two new one-dimensional chains extended by alternate benzenedicarboxylate(BDC) and 4-(2,6-di(pyrazin-2-yl)pyridin-4-yl)benzoate(L~-) connectors, {[Cu(L)(BDC)_(0.5)]·3.5 H_2 O}_n (1) and {[Zn(L)(BDC)_(0.5)] ·H_2 O}_n (2), were solvothermally synthesized. Complex 1 is in triclinic system, space group P1 with a = 9.6456(14), b = 11.1160(16), c = 12.0414(18) ?, α = 106.266(3), β = 92.277(3), γ =108.104(3)°, V = 1166.6(3) ?~3, D_c = 1.603 g·cm~(-3), Mr = 563.00, Z = 2, F(000) = 578, μ = 0.996 mm~(-1), the final R = 0.0575 and wR = 0.1386 for 3704 observed reflections with I 2σ(I). Complex 2 crystallizes in monoclinic, space group C2/c with a = 28.607(5), b = 8.9767(16), c = 19.705(4) ?, β = 125.396(3)°, V = 4125.0(13) ?~3, D_c = 1.674 g·cm~(-3), Mr = 519.79, Z = 8, F(000) = 2120, μ = 1.242 mm~(-1), the final R = 0.0487 and w R = 0.0907 for 2944 observed reflections with I 2σ(I). Resulting from the narrower band gap and broader response to visible light, the CuII-chain exhibits better photocatalytic performance towards the degradation of rhodamine B and methylene blue than those of ZnII-chain. 相似文献
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采用CP-I型汽液平衡双循环釜,测定了333.15 K时乙苯+异丙醇、邻二甲苯+异丙醇、间二甲苯+异丙醇、对二甲苯+异丙醇四个体系的汽液平衡数据,计算了该温度下四个体系的过量摩尔Gibbs自由能,并对所测数据进行了恒温下热力学一致性检验。用Wilson方程关联了实验数据,拟合精度令人满意。 相似文献
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A new magnetic MOF with cyclic triazolate and linear azido mediators, [Co2(trz)3(N3)]n 1(trz- = 1,2,4-triazolate), was hydrothermally synthesized and structurally and magnetically characterized. 1 crystallizes in the rhombohedral P63/mmc space group with a = b = 10.0716(17), c = 7.5860(14) , V = 666.4(2) 3, Dc = 1.814 g/cm3, Mr = 364.09, Z = 2, F(000) = 360, μ = 2.499 mm1, the final R = 0.0676 and wR = 0.1952 for 229 observed reflections with I 2σ(I). Complex 1 consists of linear {Co(trz)3}n chains passing through a C6 rotation axis, which are interconnected with tetrahedral CoⅡ ion by u3-trz- ligands into a hexagonal three-dimensional antiferromagnetic framework. 相似文献
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The two possible reaction paths of producing ethane on coupling reaction of methane through plasma were theoretically investigated by B3LYP and MP2 methods with 6-311G^* respectively and further compared with the previous results calculated from B3LYP/6-31G^*. The new investigated results consistently confirmed the previous conclusion. And the influences of the calculation methods and basis sets on the calculated results were also discussed. 相似文献