不同旋涂方式对铜锌锡硫硒薄膜及相应器件性能的影响

晶体质量是决定铜锌锡硫硒(Cu₂ZnSn(S,Se)₄, CZTSSe)吸收层薄膜吸收效率的关键,旋涂是溶液法制备CZTSSe吸收层的第一步,因此旋涂方式的选择至关重要。为了探究不同旋涂方式对CZTSSe吸收层薄膜质量和相应器件性能的影响,分别采用三组不同的旋涂方式制备铜锌锡硫(Cu₂ZnSnS₄, CZTS)前驱体薄膜及CZTSSe吸收层薄膜,并利用X射线衍射仪(XRD)、能谱仪(EDS)、显微拉曼光谱仪(Raman)、场发射扫描电子显微镜(FE-SEM)分析了不同旋涂方式对所制备的CZTSSe吸收层薄膜晶体结构、元素成分、相纯度、表面形貌的影响。同时,采用电流密度-电压(J-V)测试和外量子效率(EQE)测试对CZTSSe吸收层薄膜太阳电池的光电特性进行了表征。结果表明:旋涂7周期,且第一周期烘烤之前旋涂2次的效果最好,所制备的CZTS前驱体薄膜均匀,无裂纹,CZTSSe吸收层薄膜结晶度更高,薄膜表面更平整致密,晶粒大小更均匀,实现了9.63%的光电转换效率。通过对采用不同旋涂方式制备的器件的性能参数进行统计分析,得出新的旋涂方式可以提高CZTSSe薄膜太阳电池的可重复性,为将来可能的大规模商业化应用做铺垫。     

无机薄膜太阳能电池光伏材料的研究进展

太阳能是一种清洁、丰富和可持续的能源，能够满足全球日益增长的能源需求。太阳能电池是一种将太阳能转化为电能的能源转化装置，对于国家实现“碳达峰、碳中和”目标和解决未来能源问题等方面将发挥至关重要的作用。薄膜太阳能电池仅有几微米至几十微米的厚度，能够大大减少材料的损耗从而降低成本。本文对目前广泛研究的无机薄膜太阳能电池光伏材料按照组元进行归整，主要有一元体系(如a-Si)、二元体系(如CdTe、Sb₂Se₃)和多元体系[如Cu-Sn-S与Cu-Sn-Se、Cu(In,Ga)Se₂、CsPb(I_1-xBr_x)₃、Cu₂ZnSn(S,Se)₄]，通过对各类材料结构特点和光电性质进行分析，并结合例证对其电池性能予以解释说明，并对以上各类材料的发展状况进行总结并提出展望。     

水热法制备铜锌锡硫纳米材料及其光催化性能

铜锌锡硫（Cu₂ZnSnS₄）在可见光范围内光吸收系数高且具有良好的载流子迁移率,使其在光催化领域表现出了较好的应用前景。然而在实际应用中,其光催化活性及催化稳定性还需进一步提升。以氯化锌、氯化锡、氯化铜、硫脲为水热反应前驱体,添加 PEG400、OP10 为表面活性剂,通过水热反应制备 Cu₂ZnSnS₄ （CZTS）纳米粉体;使用 X 射线衍射、Raman 光谱、X 射线光电子能谱、扫描电子显微镜、透射电子显微镜等手段表征所制备铜锌锡硫材料微观结构,并研究在水热法制备过程中添加不同表面活性剂对所制备 Cu₂ZnSnS₄纳米粉体的光学带隙和光催化性能的影响。结果表明：所制备铜锌锡硫材料均具有锌黄锡矿相结构;水热法制备铜锌锡硫纳米粉体反应前驱体中添加 PEG400 和 OP10 可有效调控铜锌锡硫纳米粉体的微观结构、化学元素计量比及光学带隙,进而改变纳米粉体的光催化性能。添加 PEG400 后制备得到 Cu₂ZnSnS₄     

柔性薄膜太阳能电池的研究进展

综述了柔性薄膜太阳能电池的研究现状、发展趋势及其应用前景,分别就柔性衬底材料、硅系薄膜太阳能电池、铜铟镓硒薄膜太阳能电池、铜锌锡硫、染料敏化太阳能电池、有机太阳能电池和新型纳米材料太阳能电池进行了介绍。卷对卷以及喷墨印刷法等非真空大面积制备柔性薄膜太阳能电池的工艺,为低成本生产此类太阳能电池带来了希望,对其发展遇到的挑战进行了展望。     

电沉积制备铜系薄膜太阳能电池吸收层的研究现状

介绍了一步沉积法和多步沉积法制备铜铟硒(CISe)、铜铟硫(CIS)、铜铟镓硒(CIGS)、铜锌锡硫(CZTS)等铜系薄膜太阳能电池吸收层的电沉积技术,并对其未来发展进行了展望。     

铜锌锡硫光电转换材料性能及溶液 化学制备方法研究

铜锌锡硫（CZTS）具有资源丰富、环境友好、理论光电转换效率高等优点,是理想的薄膜太阳能电池光吸收材料。介绍了CZTS晶体结构和光电转换性能。综述了溶胶-凝胶前驱体法、溶剂（水）热法、热注入法、电沉积法、溶液法等溶液化学方法在CZTS材料制备及其薄膜太阳能电池的研究进展,讨论了目前存在的问题,并指出今后的研究方向。     

锌酸钙表面沉积Ca Sn(OH)6的制备及锌镍二次电池应用

为了改善锌镍二次电池中锌负极存在的严重极化问题，并提高锌负极的电化学性能和循环稳定性，采用水热–共沉淀法制备了表面沉积CaSn(OH)₆的锌酸钙，研究了CaSn(OH)₆的沉积对锌酸钙的形貌结构和电化学性能的影响。结果表明：水热–共沉淀法可以让CaSn(OH)₆沉积在锌酸钙表面，且制得的锌酸钙结晶度高。Ca Sn(OH)₆的沉积降低了锌酸钙的电荷转移电阻，加快了电化学反应速率，并提升了锌酸钙的耐腐蚀能力和电荷传递速率，有效的改善了锌电极的极化现象。将表面沉积Ca Sn(OH)₆的锌酸钙用作锌镍电池负极活性物质时，电池在0.2 C充放电循环70次后的容量保持率为85.34%。     

聚乙烯胺/Cu3（BTC）2-MMT-NH2混合基质膜的制备及气体传递性能

采用阳离子交换与Cu₃(BTC)₂原位合成相结合制备Cu₃(BTC)₂-MMT,同时,借助3-氨基丙基三乙氧基硅烷(KH550)氨基功能化制备Cu₃(BTC)₂-MMT-NH₂杂化材料。然后,将杂化材料添加到聚乙烯胺(PVAm)基质中作为选择性涂层涂覆到聚砜(PSf)支撑体上,制备了PVAm/Cu₃(BTC)₂-MMT-NH₂混合基质膜。通过XRD和FTIR对杂化材料的晶态结构和化学结构进行了表征,同时采用ATR-FTIR证实了Cu₃(BTC)₂-MMT-NH₂杂化材料与PVAm基质之间存在氢键相互作用。系统性研究了PVAm/Cu₃(BTC)₂-MMT-NH₂混合基质膜中MMT阳离子交换量、Cu₃(BTC)₂-MMT与KH550的质量比、Cu₃(BTC)₂-MMT-NH₂的负载量、操作压力、湿膜厚度、操作温度以及混合气作为原料气对膜CO₂渗透性、CO₂/N₂选择性的影响。结果表明：在纯气气氛,操作温度为25℃、操作压力为1 bar(1 bar=0.1 MPa)的条件下,当Cu₃(BTC)₂-MMT-NH₂负载量为3%(质量)时,膜的气体分离性能最优,CO₂渗透率为203 GPU(1GPU=10^-6 cm³·cm^-2·s^-1·cmHg^-1,1 cmHg=1333.22 Pa),CO₂/N₂选择性为100.7,远高于添加MMT、Cu₃(BTC)₂和MMT/Cu₃(BTC)₂混合物的混合基质膜。这是由于Cu₃(BTC)₂-MMT-NH₂具有层间快速传递通道且与聚合物基质有良好的相容性。此外,混合气测试条件下,混合基质膜运行360 h,仍能保持优异的CO₂分离性能稳定性。     

聚乙烯胺/Cu3（BTC）2-MMT-NH2混合基质膜的制备及气体传递性能

采用阳离子交换与Cu₃(BTC)₂原位合成相结合制备Cu₃(BTC)₂-MMT,同时,借助3-氨基丙基三乙氧基硅烷(KH550)氨基功能化制备Cu₃(BTC)₂-MMT-NH₂杂化材料。然后,将杂化材料添加到聚乙烯胺(PVAm)基质中作为选择性涂层涂覆到聚砜(PSf)支撑体上,制备了PVAm/Cu₃(BTC)₂-MMT-NH₂混合基质膜。通过XRD和FTIR对杂化材料的晶态结构和化学结构进行了表征,同时采用ATR-FTIR证实了Cu₃(BTC)₂-MMT-NH₂杂化材料与PVAm基质之间存在氢键相互作用。系统性研究了PVAm/Cu₃(BTC)₂-MMT-NH₂混合基质膜中MMT阳离子交换量、Cu₃(BTC)₂-MMT与KH550的质量比、Cu₃(BTC)₂-MMT-NH₂的负载量、操作压力、湿膜厚度、操作温度以及混合气作为原料气对膜CO₂渗透性、CO₂/N₂选择性的影响。结果表明：在纯气气氛,操作温度为25℃、操作压力为1 bar(1 bar=0.1 MPa)的条件下,当Cu₃(BTC)₂-MMT-NH₂负载量为3%(质量)时,膜的气体分离性能最优,CO₂渗透率为203 GPU(1GPU=10^-6 cm³·cm^-2·s^-1·cmHg^-1,1 cmHg=1333.22 Pa),CO₂/N₂选择性为100.7,远高于添加MMT、Cu₃(BTC)₂和MMT/Cu₃(BTC)₂混合物的混合基质膜。这是由于Cu₃(BTC)₂-MMT-NH₂具有层间快速传递通道且与聚合物基质有良好的相容性。此外,混合气测试条件下,混合基质膜运行360 h,仍能保持优异的CO₂分离性能稳定性。     

层层沉积热处理法制备超薄Cu3(BTC)2膜

基于层层沉积法,引入简单易控的热处理方式在玻璃基底表面制备出高结晶度且致密无裂缝的Cu₃(BTC)₂膜,并详细探讨热处理温度、组装时间和组装溶剂对Cu₃(BTC)₂成膜的影响。FESEM分析结果显示:膜层的厚度仅为200 nm;热处理有利于获得完整的晶体结构,且高温下膜层不会产生裂纹;组装时间为5 min或10 min,Cu₃(BTC)₂ 颗粒尺寸小且均一。然而,当组装时间延长至20 min,尺寸变得不均一,膜层表面变粗糙;通过改变组装溶剂环境,可以制备出不同维数的晶体膜。     

Synthesis and H2 uptake of Cu2(OH)3Cl, Cu(OH)2 and CuO nanocrystal aggregate

Monodispersed Cu₂(OH)₃Cl nanoplatelets, Cu(OH)₂ nanowires, CuO nanoparticles and nanoribbons with a spherical morphology were synthesized using hydrothermal and heat-treatment reactions, and their H₂ storage characteristics were examined. The Cu₂(OH)₃Cl nanoplatelets particles formed immediately after mixing the reactant, which subsequently formed larger uniform spherical particles in the submicron range. This procedure highlights a practical strategy for producing spherical Cu(OH)₂ and CuO materials consisting of monodispersed nanocrystals. The spherical aggregates of Cu₂(OH)₃Cl nanoplatelets heat-treated at 473 K could reversibly store up to 2.35 wt.% H₂ at 38 bar and 293 K.     

Optimization of electrochemically synthesized Cu3(BTC)2 by Taguchi method for CO2/N2 separation and data validation through artificial neural network modeling

Cu₃(BTC)₂, a common type of metal organic framework (MOF), was synthesized through electrochemical route for CO₂ capture and its separation from N₂. Taguchi method was employed for optimization of key parameters affecting the synthesis of Cu₃(BTC)₂. The results indicated that the optimum synthesis conditions with the highest CO₂ selectivity can be obtained using 1 g of ligand, applied voltage of 25 V, synthesis time of 2 h, and electrode length of 3 cm. The single gas sorption capacity of the synthetized microstructure Cu₃(BTC)₂ for CO₂ (at 298 K and 1 bar) was a considerable value of 4.40 mmol·g⁻¹. The isosteric heat of adsorption of both gases was calculated by inserting temperature-dependent form of Langmuir isotherm model in the Clausius-Clapeyron equation. The adsorption of CO₂/N₂ binary mixture with a concentration ratio of 15/85 vol-% was also studied experimentally and the result was in a good agreement with the predicted value of IAST method. Moreover, Cu₃(BTC)₂ showed no considerable loss in CO₂ adsorption after six sequential cycles. In addition, artificial neural networks (ANNs) were also applied to predict the separation behavior of CO₂/N₂ mixture by MOFs and the results revealed that ANNs could serve as an appropriate tool to predict the adsorptive selectivity of the binary gas mixture in the absence of experimental data.     

Underlying mechanism of the hydrothermal instability of Cu3(BTC)2 metal-organic framework

Water induced decomposition of Cu₃(BTC)₂ (BTC= benzene-1,3,5-tricarboxylate) metal-organic framework (MOF) was studied using dynamic water vapour adsorption. Small-angle X-ray scattering, Fourier transform infrared spectroscopy and differential scanning calorimetry analyses revealed that the underlying mechanism of Cu₃(BTC)₂ MOF decomposition under humid streams is the interpenetration of water molecules into Cu-BTC coordination to displace organic linkers (BTC) from Cu centres.     

Solid state protonic conductor NH4PO3–(NH4)2Mn(PO3)4 for intermediate temperature fuel cells

A new proton-conductive composite of NH₄PO₃–(NH₄)₂Mn(PO₃)₄ was synthesized and characterized as a potential electrolyte for intermediate temperature fuel cells that operated around 250 °C. Thermal gravimetric analysis and X-ray diffraction investigation showed that (NH₄)₂Mn(PO₃)₄ was stable as a supporting matrix for NH₄PO₃. The composite conductivity, measured using impedance spectroscopy, improved with increasing the molar ratio of NH₄PO₃ in both dry and wet atmospheres. A conductivity of 7 mS cm⁻¹ was obtained at 250 °C in wet hydrogen. Electromotive forces measured by hydrogen concentration cells showed that the composite was nearly a pure protonic conductor with hydrogen partial pressure in the range of 10²–10⁵ Pa. The proton transference number was determined to be 0.95 at 250 °C for 2NH₄PO₃–(NH₄)₂Mn(PO₃)₄ electrolyte. Fuel cells using 2NH₄PO₃–(NH₄)₂Mn(PO₃)₄ as an electrolyte and the Pt–C catalyst as an electrode were fabricated. Maximum power density of 16.8 mW/cm² was achieved at 250 °C with dry hydrogen and dry oxygen as the fuel and oxidant, respectively. However, the NH₄PO₃–(NH₄)₂Mn(PO₃)₄ electrolyte is not compatible with the Pt–C catalyst, indicating that it is critical to develop new electrode materials for the intermediate temperature fuel cells.     

Photocatalytic activity of Cu2O/TiO2, Bi2O3/TiO2 and ZnMn2O4/TiO2 heterojunctions

Cu₂O/TiO₂, Bi₂O₃/TiO₂ and ZnMn₂O₄/TiO₂ heterojunctions were studied for potential applications in water decontamination technology and their capacity to induce an oxidation process under VIS light. UV–vis spectroscopy analysis showed that the junctions-based Cu₂O, Bi₂O₃ and ZnMn₂O₄ are able to absorb a large part of visible light (respectively, up to 650, 460 and 1000 nm). This fact was confirmed in the case of Cu₂O/TiO₂ and Bi₂O₃/TiO₂ by photocatalytic experiments performed under visible light. A part of the charge recombination that can take place when both semiconductors are excited was observed when a photocatalytic experiment was performed under UV–vis illumination. Orange II, 4-hydroxybenzoic and benzamide were used as pollutants in the experiment. Photoactivity of the junctions was found to be strongly dependent on the substrate. The different phenomena that were observed in each case are discussed.     

Accurate low-pressure kinetics for isobutane oxidation over phosphomolybdic acid and copper(II) phosphomolybdates

A low-pressure steady-state technique has been used to investigate the rates and mechanisms of the oxidation of isobutane over H₃[PMo₁₂O₄₀], CuH₄[PMo₁₂O₄₀]₂, Cu₂H₂[PMo₁₂O₄₀]₂, Cu_2.5H[PMo₁₂O₄₀]₂, and Cu₃[PMo₁₂O₄₀]₂. Observed oxidation products over all catalysts are methacrolein, 3-methyl-2-oxetanone, acetic acid, carbon dioxide and water. The most selective catalyst for methacrolein formation at low temperatures (<496 °C) is Cu_2.5H[PMo₁₂O₄₀]₂, where both Cu(II) reduction and acid sites play a role. The least active catalyst at low temperatures is phosphomolybdic acid followed by Cu₃[PMo₁₂O₄₀]₂. This activity is reversed at higher temperatures. The 3-methyl-2-oxetanone is a unique product and is likely to be the precursor to methacrylic acid. Acetic acid is also probably a precursor to complete oxidation. Catalyst deactivation or restructuring is significant only over H₃[PMo₁₂O₄₀].     

Facile synthesis of hierarchical flower-like Ag/Cu2O and Au/Cu2O nanostructures and enhanced catalytic performance in electrochemical reduction of CO2

Novel, hierarchical, flower-like Ag/Cu₂O and Au/Cu₂O nanostructures were successfully fabricated and applied as efficient electrocatalysts for the electrochemical reduction of CO₂. Cu₂O nanospheres with a uniform size of ~180 nm were initially synthesized. Thereafter, Cu₂O was used as a sacrificial template to prepare a series of Ag/Cu₂O composites through galvanic replacement. By varying the Ag/Cu atomic ratio, Ag_0.125/Cu₂O, having a hierarchical, flower-like nanostructure with intersecting Ag nanoflakes encompassing an inner Cu₂O sphere, was prepared. The as-prepared Ag_x/Cu₂O samples presented higher Faradaic efficiencies (FE) for CO and relatively suppressed H₂ evolution than the parent Cu₂O nanospheres due to the combination of Ag with Cu₂O in the former. Notably, the highest CO evolution rate was achieved with Ag_0.125/Cu₂O due to the larger electroactive surface area furnished by the hierarchical structure. The same hierarchical flower-like structure was also obtained for the Au_0.6/Cu₂O composite, where the FE_CO (10%) was even higher than that of Ag_0.125/Cu₂O. Importantly, the results reveal that Ag_0.125/Cu₂O and Au_0.6/Cu₂O both exhibit remarkably improved stability relative to Cu₂O. This study presents a facile method of developing hierarchical metal-oxide composites as efficient and stable electrocatalysts for the electrochemical reduction of CO₂.