Synthesis of Cu_2ZnSnS_4 thin film from mixed solution of Cu_2SnS_3 nanoparticles and Zn ions

The Cu2ZnSnS4 thin film was prepared by a facile solution method without vacuum environment and toxic substance. The formation mechanism of the film was studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and Raman scattering measurements. Through cyclic voltammetry and photo-electricity tests, the electrocatalytic activity of the prepared film as the counter electrode of dye-sensitizedsolar cell was also studied. The results show that the mixed precursor solution mainly consists of Cu2SnS3 nanoparticles and Zn ions.After 550 °C annealing process on the precursor film prepared from the mixed solution, Cu2ZnSnS4 thin film is obtained. Besides, itis found that the prepared Cu2ZnSnS4 thin film has the electrocatalytic activity toward the redox reaction of I3?/I? and the dye-sensitized solar cell with the prepared Cu2ZnSnS4 thin film as the counter electrode achieves the efficiency of 1.09%.

Synthesis and electrochemical properties of Zn_2SnO_4 and Zn_2Sn_(0.8)Ti_(0.2)O_4/C

Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4-5H2O,TiCl4,ZnCl2 and N2H4-H2O were used as reactants.The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction process using the as-prepared Zn2Sn0.8Ti0.2O4 and glucose as reactants.The structure,morphology and electrochemical properties of the as-prepared products were investigated by XRD,XPS,TEM and electrochemical measurements.In addition,electrochemical Li insertion/extraction in composite Zn2Sn0.8Ti0.2O4/C were examined by ex situ XRD and SEM.The first discharge capacity of Zn2SnO4 is about 1670.8 mA-h/g,with a capacity retain of 342.7 mA-h/g in the 40th cycle at a constant current density of 100 mA/g in the voltage range of 0.05-3.0 V.Comparing with the Zn2SnO4,some improved electrochemical properties are obtained for Zn2Sn0.8Ti0.2O4,Zn2SnO4/C and Zn2Sn0.8Ti0.2O4/C.The composite Zn2Sn0.8Ti0.2O4/C shows the best electrochemical properties,and its first discharge capacity is about 1530.0 mA-h/g,with a capacity retain of 479.1 mA-h/g the 100th cycle.

Co_3O_4-Sn复合材料对锂离子电池性能的影响

锂电子电池的性能与电池负极材料密切相关,研究了锡掺杂氧化钴复合材料的水热合成及锡掺杂量对Co_3O_4-Sn复合材料的形貌、结构及电池性能的影响。利用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)等测试手段对材料进行表征。结果表明,Sn在导电基底Ti箔上以无定形态存在,且均匀分布在材料内部。同时,随着锡掺杂量的增加,会在材料表面生长一层小片状或颗粒。电化学性能测试结果表明:锡的引入可以改善锂离子电池的电化学性能,当锡掺杂量过多或过少时,都会使得电池性能下降。而且原始掺杂比例Co与Sn为1∶0.4时,电池性能最好。

Sn^(4+)和Sn^(2+)与天然丝光沸石离子交换选择性的穆斯堡尔谱研究

用Ｓｎ２＋、Ｓｎ４＋和２Ｓｎ２＋＋Ｓｎ４＋盐对天然丝光沸石进行了离子交换，测量了交换后清洗烘干样品的穆斯堡尔谱。通过对穆斯堡尔谱共振吸收峰相对面积的计算得出了样品中穆斯堡尔核的相对含量。结果表明，Ｓｎ４＋与天然丝光沸石的离子交换选择性优于Ｓｎ２＋。

离子色谱法分析ABC干粉灭火剂组分含量的必要性和可行性

为了研究ABC干粉灭火剂主要组分含量采用离子色谱法进行分析的必要性和可行性,分析了目前标准中规定的ABC干粉灭火剂主要组分含量检测方法中存在的缺陷,比较了化学滴定分析法、分光光度法、红外光谱法、电化学分析法、离子色谱法等分析方法在主要组分含量检测中的优缺点。结果表明:存在采用其他物质按现有标准规定的方法通过主要组分含量检测合格的可能。现有检测方法存在漏洞。采用离子色谱分析法可以检测出ABC干粉灭火剂溶液中的SO_(4)^(2-)、PO_(4)^(3-)、NH_(4)^(+)等阴离子和阳离子,适用于ABC干粉灭火剂中磷酸二氢铵和硫酸铵等组分含量的定量分析,能有效避免检测漏洞。因此,有必要采用离子色谱分析法对ABC干粉灭火剂中磷酸二氢铵和硫酸铵等组分含量进行定量分析,以避免出现将假冒伪劣产品误判为合格品的风险。

电沉积锡镍合金作为锂离子电池负极的研究

用电沉积方法制备了锡含量分别为0%、45.2%、62.7%、78.5%、86.1%(原子分数)的锡镍合金,用循环伏安(CV)、恒电流充放电循环(CC)、X射线衍射(XRD)和电感耦合等离子体元素发射光谱(ICP-AES)等方法研究了制备锡镍合金作为锂离子负极的性能。结果表明,随着锡含量的升高,合金的初始容量增加,但循环稳定性显著降低。含锡量为62.7%的锡镍合金具有较好的综合性能:首次放电容量达554mAh·g-1,充放电效率为82%,30次循环后放电容量保持在275mAh·g-1左右,充放电效率保持在93%.

水分对水系大容量磷酸铁锂电池电性能的影响

以水性胶聚丙烯腈多元共聚物为粘结剂、去离子水为溶剂制备磷酸铁锂(LiFePO_(4))水系浆料,采用叠片的方式制作200 Ah塑壳磷酸铁锂电池。对正极极片不同含水量的电池进行研究,结果表明:含水量200×10^(-6)的电池,首充效率93.29%;1 C常温循环2000次,容量保持83.41%,50℃高温循环600次,容量保持82.84%;7天55℃高温存储,容量保持率97.47%,容量恢复98.92%;常温存储,容量保持率98.89%,容量恢复99.93%。适合的水分不仅可以提高电池一致性,还能提高电池成本优势。