氧分压调控氧化铜薄膜生长及其表面功函数研究

本文采用反应磁控溅射法制备p型二元铜氧化物半导体薄膜，通过氧气流量调节实现Cu₂O、CuO和Cu₄O₃薄膜的可控生长。所制备薄膜的形貌与结构分别利用扫描电子显微镜、X射线衍射仪以及拉曼光谱进行表征。经紫外可见分光光度计测量可知，Cu₂O、CuO和Cu₄O₃薄膜的带隙分别为2.89 eV、1.55 eV和2.74 eV。为进一步研究Cu₂O、CuO和Cu₄O₃薄膜的表面物理性质，基于Kelvin探针力显微镜(KPFM)技术直接测量了薄膜样品与探针尖端间的接触电位差(V_CPD),结果表明Cu₂O、CuO和Cu₄O₃薄膜的表面功函数都随着温度的升高而呈现逐渐减小的趋势。     

Ca(H2PO4)2-H3PO4-K2SO4体系中石膏晶型及形貌调控

为将Ca(H₂PO₄)₂制备KH₂PO₄过程中的石膏资源化利用,以H₃PO₄与CaCO₃反应制备Ca(H₂PO₄)₂溶液,并与K₂SO₄溶液反应,进行Ca(H₂PO₄)₂-H₃PO₄-K₂SO₄体系中石膏晶型和形貌调控研究。结果表明:通过改变反应时间、反应温度、SO^2-₄过量系数和CaO含量等参数可对Ca(H₂PO₄)₂-H₃PO₄-K₂SO₄体系中石膏晶型和形貌进行调控,制得短柱状α-CaSO₄·0.5H₂O。体系在温度高于95 ℃和CaO含量为3.0%~5.0%(质量分数,下同)时形成α-CaSO₄·0.5H₂O,在CaO含量为5.5%主要形成CaSO₄·2H₂O;反应时间长于20 min和SO^2-₄过量系数大于1.4将形成K₂SO₄(CaSO₄)₅·H₂O,导致石膏晶体表面缺陷增加。本实验条件下,适宜反应条件为:反应时间10 min、反应温度95 ℃、SO^2-₄过量系数1.2和CaO含量5.0%,此条件下可制得长度42~70 μm、直径13~24 μm的短柱状α-CaSO₄·0.5H₂O,其抗折和抗压强度分别可达5.61 MPa和33.74 MPa,滤液中钾收率和脱钙率分别可达94.23%和83.80%。     

基于5-氨基烟酸的锰金属有机框架的合成、结构及荧光传感性质

室温下,通过溶液法将5-氨基烟酸(5-Hana)与MnCl₂反应,成功合成了一例新的三维Mn(II)金属有机框架[Mn₂(5-ana)₄(H₂O)]_n(命名为Mn-MOF)。通过X射线单晶衍射、X射线粉末衍射、元素分析、红外光谱、热重分析、紫外-可见光谱和荧光光谱法对配合物的结构和性质进行表征。结构分析表明,配合物属单斜晶系,具有双节点(2,8)-c配位网络结构,其中[Mn₂(CO₂)₂(H₂O)]二聚单元作为8-连接节点,5-ana^-配体作为2-连接节点。分子范德瓦耳斯表面静电势(ESP)分析表明,5-ana^-配体的第一反应位点在羧基氧原子附近,ESP最小值为-143.37 kcal·mol^-1,第二和第三反应位点分别位于吡啶环和氨基氮原子附近。Mn-MOF常温下具有良好的热稳定性。荧光光谱测试显示配合物在256 nm光激发...     

具有n-n型异质结的复合材料Bi2S3/MIL-125(Ti)光电性能研究

以硫代硫酸钠·五水合物(Na₂S₂O₃·5H₂O)、硝酸铋·五水合物(BiN₃O₉·5H₂O)为硫源和铋源，尿素(CON₂H₄)为结构导向剂，制备了纳米棒状结构的硫化铋(Bi₂S₃),使其原位生长在MIL-125(Ti)的笼状结构表面。PEC性能测试显示，在0.5 mol·L^-1的硫酸钠电解液(pH=6.0)中，Bi₂S₃/MIL-125(Ti)_0.07(MIL-125(Ti)加入量为0.07 g)的复合材料表现出最高的光电性能。光电性能的显著增强主要取决于Bi₂S₃/MIL-125复合材料的带隙重整效应，对紫外光以及可见光的吸收能力显著提高。但由于Bi₂S₃/MIL-125...     

H2SO4-H2O中硝酸铜对脱硫石膏晶须生长的影响

以处理后的脱硫石膏为原料,在H₂SO₄-H₂O体系中以Cu(NO₃)₂为晶形控制剂采用水热法制备脱硫石膏晶须,探讨了Cu(NO₃)₂对脱硫石膏晶须生长的影响机理。结果表明:Cu(NO₃)₂对脱硫石膏有明显促溶作用,其中Cu²⁺可减小溶液中各离子的活度系数,使溶液中的Ca²⁺浓度增大。NO^-₃通过静电作用在Ca²⁺周围聚集并对SO^2-₄产生屏蔽作用,导致脱硫石膏继续溶解并使Ca²⁺和SO^2-₄的浓度处于相对稳定状态,有利于半水脱硫石膏晶体的形核与生长。此外,Cu²⁺还可在晶须的生长过程中选择性吸附在晶须表面,生成CuSO₄,促进了脱硫石膏的结晶生长,最终在Cu(NO₃)₂用量为2.0%(质量分数)时制备的脱硫石膏晶须长径比约为73。     

铅基卤化物钙钛矿太阳电池的模拟研究

多元硫化物Cd_0.5Zn_0.5S和氧化亚铜Cu₂O载流子迁移率较大,且其制作工艺相对于传统的电子传输层和空穴传输层更为简单,因此这两种材料在钙钛矿太阳电池中具有很好的应用潜力。本文利用SCAPS-1D软件对以Cu₂O和Cd_0.5Zn_0.5S为传输层、以铅基卤化物钙钛矿为吸收层的太阳电池进行模拟,主要研究了该器件的材料厚度、掺杂浓度、禁带宽度等因素对太阳电池性能的影响。结果表明:当光吸收层(CH₃NH₃PbI₃)厚度开始增大时电池性能逐渐提高,但是增大到一定厚度时,电池性能下降,光吸收层的最佳厚度为400 nm;当光吸收层的缺陷态密度小于1.0×10¹⁴ cm^-3时,缺陷态密度对电池性能的影响比较小;此外,铅基卤化物钙钛矿的禁带宽度对电池性能有重要影响,最佳禁带宽度为1.5 eV左右。通过模拟,得到了优化后的性能参数为:开路电压为1.010 V,短路电流密度为31.30 mA/cm²,填充因子为80.01%,电池转换效率为25.20%。因此,Cu₂O/CH₃ NH₃PbI₃/Cd_0.5Zn_0.5S钙钛矿太阳电池是一种很有发展潜力的光伏器件。     

基于四核铜簇单元构筑的配位聚合物及光催化降解性能

以1,3-双咪唑基丙烷(1,3-BIP)、1,3,5-苯三甲酸(H₃BTC)和Cu(NO₃)₂·3H₂O为原料,在溶剂热条件下合成了Cu(II)配位聚合物[Cu₂(μ₃-OH)(1,3-BIP)(BTC)]_n(SNUT-20),并用元素分析、热重分析、红外光谱、单晶X射线衍射等表征手段对配位聚合物进行了表征。单晶X射线衍射解析结果表明,配位聚合物SNUT-20是一个以四核铜簇作为次级结构单元,通过混合配体的进一步连接,形成一个3,8双节点的拓扑结构。此外,配位聚合物SNUT-20对罗丹明B(RhB)、亚甲基蓝(MB)和甲基橙(MO)表现出良好的光催化降解性能,对RhB、MB、MO的降解率分别达到了81.5%、89.4%和48.3%。     

1,3,5-三(羧基甲氧基)苯镍配位聚合物的合成、晶体结构及性质研究

采用溶剂热法,1,3,5-三(羧基甲氧基)苯为定向配体和乙酸镍反应构筑了一个新型的金属配位聚合物[Ni(TB)₂(H₂O)₂]_n·2H₂O,其中H₃TB=1,3,5-三(羧基甲氧基)苯,通过元素分析、IR及X射线单晶衍射对配合物结构进行表征,并研究其荧光性质、热稳定性及Hirshfeld表面作用力。单晶结构分析表明,该配合物属于三斜晶系,空间群$P \overline{1}$,配合物中心离子Ni(Ⅱ)分别与来自两个水分子上的氧原子及四个不同1,3,5-三(羧基甲氧基)苯配体的羧酸氧原子配位,形成六配位的NiO₆八面体构型,并通过与1,3,5-三(羧基甲氧基)苯配体的氧原子配位不断延伸形成具有孔洞结构的一维链状构型。配合物具有良好的荧光性能和热稳定性。Hirshfeld表面作用分析表明配合物分子中O…H/H…O作用占主导且占比为39.0%,而H…H的作用力占比为25.9%,O…O的作用力占比为13.6%。     

微反应器策略实现γ-CuI的形貌调控

γ-CuI较宽的能带空隙及较高的离子电导率等特点，使其在光能利用和超快闪烁材料领域有着广泛的应用。γ-CuI的形貌往往对其结构性质有重要的影响，精准地调控其形貌有很大的意义。因此，本文采用微反应法，通过控制不同NH₃·H₂O用量、Cu源、管内反应停留时间及合成温度等因素，结合SEM、XRD和FT-IR等测试手段，对不同合成条件下制备得到的γ-CuI的晶型与形貌进行了研究。并对传统液相沉淀法和微反应法制备的γ-CuI进行了比较。结果表明，当NH₃·H₂O使用量(C_NH3·H2O/C_N2H4)为0.4、管内停留时间为10 s、反应温度为20℃的条件下达到90.5%的最高产率。其中，NH₃·H₂O的使用量对形貌的影响最大，当NH₃·H₂O的使用量为0.4时，合成了形貌均一的棒状γ-CuI。...     

Bi2Te3纳米晶溶剂热合成及表征

采用溶剂热方法,在水合肼溶剂中通过添加适量表面活性剂十二烷基硫酸钠(SDS),在180 ℃下反应10 h后成功地制备了不同形貌的纯相Bi2Te3纳米晶,包括纳米颗粒、纳米棒和花瓣状纳米片.用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、能量色散谱仪(EDS)对产物进行了表征,探讨了表面活性剂用量和温度对产物形貌的影响,提出了可能的形成机理.     

Effect of heating and cooling atmospheres on colors of glaze and glass containing copper

ESR and ESCA analyses of a copper red glaze prepared by firing under a strongly reducing atmosphere followed by oxidation during a cooling period showed that Cu¹⁺ and Cu₂O were major species in it. From the investigation of behavior and chemical states of copper and tin under various firing conditions, mechanisms of the formation of Cu₂O and its protection were assumed as follows: Cu²⁺ and Sn⁴⁺ are reduced to metals during reducing firing and then the metals aggregate in the glaze surface layer, forming alloy. In the next oxidation process, metallic copper and tin are oxidized to Cu₂O or Cu¹⁺ and SnO respectively. Due to the affinity of SnO on Cu₂O for glass, glass containing Sn²⁺ surrounds and consequently protects Cu₂O from excessive oxidation.

A colorless copper glass before striking contained copper mainly as Cu¹⁺. ESCA analysis showed that striking of the glass caused the selective formation of Cu₂O.     

Influence of decomposition parameters on agglomeration process and total soda content in precipitated Al(OH)3

Grain size composition of precipitated Al(OH)₃ is dependent on the mechanism of decomposition process of the caustic solution which determines crystal growth process, agglomeration process and secondary nucleation. Because the literature data shows that the growth rate is very low, the agglomeration process plays an important role in increasing the initial particle size. On the other hand, the agglomeration process enables the inclusion of impurities by the grain boundary of sticking Al(OH)₃ particles, above all, the inclusion of soda Na₂O.

In this paper we investigate the influence of caustic soda concentration Na₂O_(c), that is the supersaturation of the solution, seed charge and seed grain size on the agglomeration and secondary nucleation processes and total soda content in precipitated Al(OH)₃. The results have shown that the factor which causes the increase of the agglomeration process also causes the increase of total soda content in precipitated Al(OH)₃.     

萘羧酸膦酸铜配合物的合成与表征

本文以萘羧酸膦酸配体(5-pncH₃=(5-phosphono-1-naphthalenecarboxylic acid)和高氯酸铜为原料,在水热条件下自组装得到了一维配合物Cu_0.5(5-pncH₂)(H₂O)_1.5(1)。采用单晶衍射(X-Ray)、元素分析(EA)、红外光谱(FT-IR)、粉末衍射(Powder X-Ray)、热重分析(TG-DTG)对配合物进行晶体结构和热稳定性表征。晶体结构分析表明:该配合物结晶于正交晶系,Pbcm空间群,a=0.667 88(2) nm,b=0.884 14(2) nm,c=4.174 03(9) nm。配合物1的晶体结构中相邻的金属Cu^II离子由配位水分子连接成一维锯齿状无机链。这些相邻的无机链通过萘羧酸膦酸配体上未配位的双重羧基氢键连接成层状结构。热稳定性研究表明,配合物呈现出逐级分解过程,在350 ℃以下能够保持配合物骨架结构的稳定性。     

Crystal growth of metal fluorides for CO2 laser operation I. The necessity of the RAP approach

The 10 μm transparency of halides addresses directly its oxide content. The conversion from oxide to fluoride must have ΔG0. HF(g) is different from the other hydrogen halides because its ΔG of formation is larger than that of H₂O(g). Decrease in the hydrolysis of RF₃ (R=rare earth) influences the crystal phase stability and the tendency of the crystal to crack. The base-to-acid behavior of +3 rare earths provides quantitative support. HF(g) and RAP (reactive atmosphere process) CF₄(g) formations of YF₃ from Y₂O₃ are given in detail. This indifference to HF(g) is reported also in the congruent growth of CaF₂, SrF₂, and BaF₂. The explanation is seen in ZrF₄, HfF₄, and ThF₄. Although RAP does not use HF(g), it permits the congruent growth of good-quality single crystals with very low H₂O(g) content.     

基于2,5-二溴对苯二甲酸配体的锌/钴配合物合成、晶体结构及性质

将有机物2,5-二溴对苯二甲酸(H₂L₁)和2,2′-联吡啶(L₂)作为双配体,使用溶剂热法和七水合硫酸锌(ZnSO₄·7H₂O)、六水合硝酸钴(Co(NO₃)₂·6H₂O)分别反应,得到配合物[Zn(L₁)(L₂)(H₂O)]_n(1)和配合物[Co(L₁)(L₂)(H₂O)]_n(2)。采用单晶X射线衍射、元素分析、红外光谱、紫外光谱、荧光光谱、热重分析等测试方法对这两种物质进行分析研究。单晶测试结果表明配合物1是单斜晶系,以Zn²⁺配位连接L^2-₁与L₂形成一维链状结构,各条链在分子间氢键和π…π共轭作用下有规律地堆叠形成三维网络结构。配合物2是三斜晶系,Co1离子和Co1ⁱ离子由H₂L₁上的羧酸氧原子O4和O4ⁱ连接,形成双齿螯合的配位结构单元,以Co²⁺配位连接 L^2-₁和L₂形成二维网格结构,各层在O—H…O分子间氢键和范德瓦耳斯力作用下有规律的堆叠形成三维网络结构。配合物1和2均含有芳香杂环、羧基杂环和氮杂环,具有良好的荧光性质和热稳定性,最大发射波长分别为345 nm和333 nm。     

Hydrothermal growth of crystals under visual examination

Hydrothermal growth, recrystallization and synthesis of -TeO₂. Te₆O₁₁C₁₂, CuBr, PbI₂, PbBr₂, PbCl₂ SbNbO₄ monocrystals in an apparatus with visual examination are considered. In the apparatus with an optical quartz reactor the experiments were carried out to study the hydrodynamics of the solution in the homogenous and binary phase gas-liquid media. The data obtained agree well with those calculated thus permitting us to take into account the effect of hydrodynamical environment on supersaturation and mass transport kinetics. This fact was demonstrated while studying kinetics of mass transport of -TeO₂ on seeds in homogenous and binary phase gas liquid media. Solubility of TeO₂ monocrystals and kinetic properties of their growth were studied in their dependences on physical, chemical and hydrodynamical parameters and the growth mechanism was suggested. Simultaneous growth of tellurium dioxide and oxychloride monocrystals was first observed in the system TeO₂-HCl-H₂O in homogenous and binary phase solutions, the corresponding dependences on temperature, temperature gradient and HCl concentration have been analyzed. The mechanism of simultaneous growth of these crystals and its relationship with the composition of the crystallization medium are considered. The apparatus with visual examination was demonstrated to be useful in the synthesis and recrystallization of PbHal (Hal = I, Br, Cl) monocrystals under various PT conditions.     

Synthesis, growth and characterization of a new laser upconversion crystal Ba2ErCl7

A modified method to synthesize the new laser upconversion material Ba₂ErCl₇ using Er₂O₃, BaCl₂ 2H₂O and NH₄CI is reported for the first time in this paper. Single crystals up to 5–8mm in diameter and 10–20 mm in length have been grown by Czochralski method. The transmittance spectra of Ba₂ErCl₇ single crystal has first been measured by using an HITACHI U-3500 spectrophotometer. There are three intense absorption peaks ⁴I_9/2⁴I_11/2 and ⁴I_13/2 in the infrared range which can be excited by 803nm, 980nm and 1.5μm laser diodes (LDs), respectively. The cut-off wavelength of the crystal is 230mn. Intense green luminescence can be observed when the crystal is pumped by a ED at 803nm. The formation of the defects is also discussed.