膜蒸馏技术在溶液蓄能中的应用

本文以太阳能热利用和蓄能技术为研究背景,提出了一种基于膜蒸馏的太阳能溶液蓄能模式。采用疏水性聚偏氟乙烯中空纤维膜为膜蒸馏材料,基于膜蒸馏常温操作、小温差大传热面积的特点,利用膜材料微观上的高比表面积和单位体积的高接触面积为载体,选取50%溴化锂溶液为工质,以减压膜蒸馏的方式进行溶液浓缩和潜能存储,浓缩后的溶液可作为吸收式热力系统的工质。为此,针对50%的溴化锂溶液进行了减压膜蒸馏实验,对不同溶液温度、溶液流量在不同真空度下进行减压膜蒸馏实验,得到了3组实验数据。根据实验结果,对膜蒸馏式溶液蓄能系统进行分析,结果表明:蓄能密度可以达到245 kJ/kg,单位面积的膜组件可以产生0.27~0.40 kW的蓄能量,膜蒸馏式溶液蓄能为太阳能利用、吸收式热力系统和蓄能技术提供了一种新的应用方法和途径。     

发光层厚度对基于CdSSe/ZnS量子点LED性能的影响

采用粒径约为10 nm的CdSSe/ZnS量子点层作为发光层,制备了叠层结构的量子点发光器件,研究了量子点层厚度对其薄膜形貌及量子点发光二极管性能的影响.原子力显微镜测试结果表明:量子点层过厚时,量子点颗粒发生团聚,且随着厚度的降低,团聚现象减弱;当量子点层厚度和量子点粒径相当时(约为10 nm),量子点呈单层排列且团聚现象基本消失;而量子点层厚度低于10 nm时,薄膜出现孔洞缺陷.器件的电流-电压-亮度等测试结果表明:量子点发光二极管中量子点层厚度与器件的光电特性密切相关,量子点层厚度为10 nm的器件光电性能最优,具有最低的启亮电压4.2V,最高的亮度446 cd/m2及最高的电流效率0.2 cd/A.这种通过控制旋涂转速改变量子点层厚度的方法操作简单、重复性好,对QD-LED的研究具有一定应用价值.     

Research on flexible silver nanowire electrode for organic light-emitting devices

By spin-coating silver nanowires(AgNWs) and polymethyl methacrylate(PMMA), applying pressure imprint and plasma treatment, we obtained flat Ag NW thin film with a sheet resistance of 20 Ω/sq and a transmittance of 78% at 550 nm with low surface roughness. No significant change in sheet resistance was observed after cyclic bending(bending radius is 5 mm) test and tape test. After 1 000 bending tests, the change rate of sheet resistance was only 8.3%. The organic light-emitting devices(OLEDs) were prepared by using such Ag NW electrodes and a maximum brightness of 5 090 cd/m² was obtained. Compared with the Ag NWs electrode without any treatment, the present Ag NW electrodes have lower sheet resistance and better hole injection. Our results show spin-coated with flat layers, embossed and plasma-treated Ag NW electrodes are suitable for manufacturing flexible organic optoelectronic devices.     

Research on the impact of spin coating silver nano clusters on the performance of OLED devices

To achieve uniform distribution of silver nano clusters (SNCs) on substrate and reveal its effect on the performance of organic light-emitting diode (OLED), the SNCs incorporated OLED was fabricated and SNCs were coated by multi-step spin coating. Compared with the device without SNCs film, the brightness and current efficiency of the OLED devices with SNCs film were highly raised. The enhancement is attributed to SNCs induced local surface plasmon (LSP) oscillation, which can increase the radiative rate of excitons on Alq₃ molecules.     

基于单片机的全彩OLED静态显示驱动接口电路

针对奇晶公司生产的CMEL CO283QGLD-T型OLED显示模块的特性,以宏晶科技的STC11L60XE单片机为主控制器,进行OLED显示模块与单片机在SPI模式下的硬件接口设计和软件设计,并实现了分辨率为240×320的全彩图片静态显示。所设计的OLED驱动电路具有通用性,且可显示多种测试图片用于中小尺寸OLED的显示性能测试和评定。     

有机酸修饰ITO对OLED器件性能的影响

分别采用二氯苯氧乙酸和溴乙酸对ITO表面进行修饰,研究其对OLED器件(ITO/PVK/ FIrPic:SimCP/TPBi/LiF/Al)性能的影响.结果显示,相较于未修饰的器件,采用二氯苯氧乙酸修饰后的器件最大亮度由673.4 cd/m2提升至1 875.2 cd/m2,同时器件的启亮电压由6.2V降至5.3V.研究发现,有机酸处理能够改变ITO的表面能和功函数,一方面改变ITO和后续膜层的接触性能,影响后续膜层的成膜;另一方面也可以有效减少ITO与有机层间的势垒,提升载流子注入.这种用有机酸修饰ITO阳极的方法工艺简单,能有效降低空穴注入势垒,优化ITO和有机层的接触性能,对器件性能的提升起到一定的促进作用.     

反向冲压机构在翻边冲孔模中的改进方案

现代汽车工业,综合安全、节能、降本、低碳减排等全方位因素,有利于汽车轻量化的板金,在高强板选用上越来越多;汽车模具在结构上逐步趋于紧凑化,二合一工序应用开始普及。阐述了一种新型反向冲压机构在汽车后地板翻边冲孔模中的应用,与传统反向冲压机构相比,该机构体积显著缩小、应用强力氮气弹簧和拉伸弹簧组合,实现强力复位,反向冲压成形后的卸料和机构滑块回程更为可靠,推广价值较高。     

ICP-OES法测定硅碳负极材料中的硅和17种杂质元素

采用HF+HNO_3分解锂离子电池硅碳负极材料,在60℃温度下分解30 min,样品分解完全且几乎不损失。使用带氢氟酸进样系统的ICP-OES测试硅碳负极材料中的硅和铝、锂、钴、钙、镉、铬、铜、铁、钾、镁、锰、钠、镍、铅、钛、钒、锌,3次测试硅的加标回收率为99.17%,精密度为0.07%。其他元素的加标回收率为91.11%～115.66%,精密度在0.24%～5.66%。该方法操作简便快捷,基体干扰小。     

Achieving high-performance phosphorescent organic light-emitting diodes using thermally activated delayed fluorescence with low concentration

We fabricated phosphorescent organic light-emitting diodes (PhOLEDs) using thermally activated delayed fluorescence (TADF) material 10,10''-(4,4''-sulfonylbis(4,1-phenylene)) bis(9,9-dimethyl-9,10-dihydroacridine) (DMAC-DPS) with low concentration, which showed better performance compared with 1,3-bis(carbazole-9-yl) benzene (mCP) based devices. When the concentration of DMAC-DPS was 1wt%, the driving voltage of the device was only 3.3 V at 1 000 cd/m2, and the efficiency and lifetime of the device were effectively improved compared with those of mCP based devices. The result indicated that DMAC-DPS could effectively improve the performance of phosphorescent devices. We believe that the better device performance can be attributed to the optimization of the energy transfer process in the emitter layer and lifetime of triplet excitons by DMAC-DPS. The study may provide a simple and effective strategy to achieve high-performance OLEDs.     

Transparent conductive PVP/AgNWs films for flexible organic light emitting diodes by spraying method

In this study, a simple spraying method is used to prepare the transparent conductive films (TCFs) based on Ag nanowires (AgNWs). Polyvinylpyrrolidone (PVP) is introduced to modify the interface of substrate. The transmittance and bending performance are improved by optimizing the number of spraying times and the solution concentration and controlling the annealing time. The spraying times of 20, the concentration of 2 mg/mL and the annealing time of 10 min are chosen to fabricate the PVP/AgNWs films. The transmittance of PVP/AgNWs films is 53.4%—67.9% at 380—780 nm, and the sheet resistance is 30 Ω/□ which is equivalent to that of commercial indium tin oxide (ITO). During cyclic bending tests to 500 cycles with bending radius of 5 mm, the changes of resistivity are negligible. The performance of PVP/AgNW transparent electrodes has little change after being exposed to the normal environment for 1 000 h. The adhesion to polymeric substrate and the ability to endure bending stress in AgNWs network films are both significantly improved by introducing PVP. Spraying method makes AgNWs form a stratified structure on large-area polymer substrates, and the vacuum annealing method is used to weld the AgNWs together at junctions and substrates, which can improve the electrical conductivity. The experimental results indicate that PVP/AgNW transparent electrodes can be used as transparent conductive electrodes in flexible organic light emitting diodes (OLEDs).