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碱式碳酸铜在空气中的热分解动力学   总被引:2,自引:0,他引:2  
用羞热分析(DTA)和热重分析(TG)测定了碱式碳酸铜Cu3(OH)2CO3在空气中的热分解曲线,运用X-射线粉末衍射(XRD)、透射电镜(TEM)等技术对碱式碳酸铜热重分解产物进行了表征。实验结果表明,碱式碳酸铜在空气中分解生成粒径约为10nm的CuO,用Friedman法和Flynn-wall-Ozawa(FWO)法求取了Cu2(OH)2CO3热分解的活化能为175.53kJ/mol,并用多元线性回归给出了分解过程的可能机理函数。  相似文献   
2.
Donor-acceptor (D-A) type fully conjugated block copolymer systems have been rarely reported due to the challenges in synthetic approaches to prepare well-defined low-polydispersity products. In this work, fully conjugated block copolymers are synthesized in a one-pot reaction through Stille coupling polycondensation, by utilizing the end-functional polymer copolymerization method. End-functional P3HT are copolymerized with AA (2,7-dibromo-9-(heptadecan-9-yl)-9H-carbazole) and BB (4,7-bis(5-(trimethylstannyl)thiophen-2-yl)benzo[c][1,2,5]thiadiazole, TBT) type monomers, respectively. The orthogonal solubility between the very soluble P3HT donor and the insoluble PCDTBT acceptor block improves the purity of block copolymers as well as distinct nano-scale phase-separation compared with other reports on miscibility of donor and acceptor polymer block. Further purification via preparative GPC is carried out to remove the excess of unreacted P3HT and free PCDTBT as well as to achieve low polydispersity of block copolymers. The chemical structure of the P3HT-b-PCDTBT block copolymers are verified via 1H-NMR, and further confirmed by FTIR spectra. The block copolymer shows broad absorption and moderate optical band gap of 1.8 eV. Furthermore, the fully conjugated block copolymer films exhibit significant fine structures, much smoother film morphology compared to P3HT/PCDTBT polymer blends. By adding a small amount of block copolymer P3HT-b-PCDTBT as a compatibilizer into the bulk-heterojunction of P3HT:PC61BM blends, polymer solar cells with an 8% increase of short circuit current (J sc and 10% increase of power conversion efficiency (PCE) are achieved owing to the improvement of the active-layer film morphology. To the best of our knowledge, this is the first report on donor-acceptor type fully conjugated block copolymer as an effective ternary additive in polymer: fullerene bulk heterojunction solar cells.  相似文献   
3.
磷光有机发光二极管(PHOLEDs)相对于传统的荧光有机电致发光具有更高的量子效率,在平板显示和固态照明方面有极大的应用前景.本工作将近几年来外量子效率高于20%的蓝光PHOLEDs中小分子主体材料进行总结,并按空穴传输型、电子传输型和双极传输型主体材料分类,重点介绍这些材料的分子结构、三线态能级、HOMO/LUMO能级、热稳定性、形态稳定性以及作为蓝光PHOLEDs主体材料的器件性能,以期对主体材料的研究及OLED产业化提供参考价值.  相似文献   
4.
设计合成了三种以(甲氧基)三苯胺为给体(Donor,D),苯环为共轭π桥,羰基(或双氰基乙烯基)为受体(Acceptor,A)的D-π-A-π-D型有机小分子空穴传输材料1-T、1-OT和1-OTCN.对三个化合物的热稳定性、光物理以及电化学性质进行表征,并将它们作为空穴传输材料运用至钙钛矿太阳能电池中,研究其光伏特性.实验结果表明,通过引入具有不同给(吸)电子能力的基团,可对材料的光电性质进行有效调控.基于小分子空穴传输材料1-T、1-OT和1-OTCN的非掺杂反向钙钛矿太阳能电池器件光电转化效率(PCE)分别为13.0%、14.4%以及16.8%.其中,基于甲氧基和双氰基修饰的1-OTCN电池器件,由于空穴传输层与钙钛矿界面发生更有效的电荷跃迁和收集,电荷复合较少,因此器件性能最佳,1-OTCN的疏水性质使得其对应器件效率和水氧稳定性均优于常用空穴传输材料PEDOT:PSS(PCE:13.0%).  相似文献   
5.
ZnAc2·2H2O在空气中的热分解动力学研究   总被引:2,自引:0,他引:2  
用TG/DTA,DSC和XRD技术研究了固态物质ZnAc2.2H2O在空气中的热分解过程.结果表明,ZnAc2.2H2O在空气中发生两步分解,其失重率与理论计算失重率相符.XRD结果表明,ZnAc2.2H2O分解的最终产物为ZnO.用Friedman法和Flynn-Wall-Ozawa(FWO)法求得分解过程的活化能E,并通过多元线性回归方法给出了可能的机理函数.ZnAc2.2H2O在空气中两步分解的活化能分别为119.82和66.82kJ/mol.  相似文献   
6.
消旋卡多曲在空气中的热分解动力学   总被引:11,自引:0,他引:11  
陶友田  占丹  张克立 《化学学报》2006,64(5):435-438
用热分析(TG/DTA/DSC)技术研究了消旋卡多曲(C21H21NO4S)在空气中的热分解过程. 热分析结果表明, 消旋卡多曲在空气中一步分解, 其熔点为77.4 ℃. 用Friedman法, Flynn-Wall-Ozawa (FWO)法和ASTM E698法求取了分解过程的活化能E, 并通过多元线性回归法给出了可能的机理函数.  相似文献   
7.
本文成功搭建了一套集成了能谱分析功能的时间分辨光电子显微镜系统(TR-PEEM),能够对电子密度分布进行时间分辨和能量分辨的成像.这套4D显微镜在空间、时间、能量多维度获取电子动力学信息提供了前所未有的手段.本文使用184 fs的时间分辨、150 meV的能量分辨和优于150 nm的空间分辨对半导体进行了测量,在Si(111)表面的Pb岛上获得了微区光电子能谱和能量分辨的TR-PEEM图像.实验结果表明,这套系统是进行异质结载流子动力学观察的有力工具,有助于在亚微米/纳米空间尺度和超快时间尺度上加深对半导体性质的理解.  相似文献   
8.
A series of novel hyperbranched polymers(HBPs) consisting of a 2,7-subsituted 9-(heptadecan-9-yl)-9H-carbazole unit(A_2+A_2') and a tetra-substituted green thermally activated delayed fluorescence(TADF) dye of 2,3,5,6-tetra(9Hcarbazol-9-yl)-4-pyridinecarbonitrile(4CzCNPy, B4) have been synthesized via Suzuki cross-coupling reaction following an "A2+A2'+B_4" method. The polymers are named according to the polymerization ratio of 4CzCNPy monomer(5 mol%, 10 mol% and 15 mol% for HBPs of P2-P4 respectively, and 0 mol% for the control linear polymer P1). Their thermal, optoelectronic and electrochemical properties have been characterized by a combination of techniques. All the polymers exhibit high thermal stability with the decomposition temperatures(Td) above 400 ℃ and glass transition temperatures(Tg) up to 98 ℃. Unfortunately, the incorporation of TADF moiety into these HBP materials induced non-TADF characteristics. However, when the HBPs functionalized as the host for our previously developed 4CzCNPy TADF dopant in solution processed devices, maximum external quantum efficiency of 5.7% and current efficiency of 17.9 cd/A have been achieved in P3-based device, which is significantly higher than those of 1.5% and 4.2 cd/A for the linear polymer P1.  相似文献   
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