基于含芴菲并咪唑衍生物的可湿法加工的蓝光有机电致发光器件

设计合成了一种新型A-D-A含芴菲并咪唑和炔基基团的蓝光分子( FI),采用紫外吸收、光致发光光谱和循环伏安对材料进行了表征,发现该物质具有稳定的蓝光发射。采用旋涂的方法制备了非掺杂蓝光有机发光二极管,器件的最大电流效率为1.52 cd·A-1,最大功率效率为0.63 lm·W-1.     

基于苯基修饰策略的新型可溶液加工红光铱配合物的设计、合成及电致发光性能研究

利用向环金属配体的C-Ir键的对位进行苯基取代这一结构修饰策略,成功合成了两种新型铱（III）配合物（3PhNbt）₂Ir（acac）和（3OMePhNbt）₂Ir（acac）.相较其橙光发射的母体化合物（Nbt）₂Ir（acac）,两个目标化合物的抗结晶性、非晶态热稳定性及溶解性均有显著提高,其磷光发射带也发生了5~10 nm的红移.以（3PhNbt）₂Ir（acac）和（3OMePhNbt）₂Ir（acac）为发光客体材料所制备的单层溶液加工电致红光器件,其最大发光亮度分别为1830 cd·m^-2和6630 cd·m^-2,最大电流效率分别为2.4 cd·A^-1和8.7 cd·A^-1,CIE1931色坐标分别为（0.61,0.39）和（0.62,0.38）.相比之下,以母体化合物（Nbt）₂Ir（acac）为发光客体材料所制备的参比器件,其最大发光亮度则为1620 cd·m^-2,最大电流效率仅为1.5 cd·A^-1,CIE1931色坐标为（0.59,0.41）.上述研究结果表明：向C-Ir键对位进行苯基修饰可以在提高铱（III）配合物的可溶液加工性能的同时,获得更为红移的电致发光波长,是一种简单而有效的红光铱（III）配合物的分子设计策略.     

Effect of additives on the photovoltaic properties of organic solar cells based on triphenylamine-containing amorphous molecules

Photovoltaic performance of the organic solar cells(OSCs)based on 2-((5′-(4-((4-((E)-2-(5′-(2,2-dicyanovinyl)-3′,4-dihexyl-2,2′-bithiophen-5-yl)vinyl)phenyl)(phenyl)amino)styryl)-4,4′-dihexyl-2,2′-bithiophen-5-yl)methylene)malononitrile(L(TPAbTV-DCN))as donor and PC70BM as acceptor was optimized using 0.25 vol%high boiling point solvent additive of1-chloronaphthalene(CN),1,6-hexanedithiol(HDT),or 1,8-diodooctane(DIO).The optimized OSC based on L(TPA-bTVDCN)–PC70BM(1:2,w/w)with 0.25 vol%CN exhibits an enhanced power conversion efficiency(PCE)of 2.61%,with Voc of0.87 V,Jsc of 6.95 mA/cm2,and FF of 43.2%,under the illumination of 100 mW/cm2 AM 1.5 G simulated solar light,whereas the PCE of the OSC based on the same active layer without additive is only 1.79%.The effect of the additive on absorption spectra and the atomic force microscopy images of L(TPA-bTV-DCN)–PC70BM blend films were further investigated.The improved efficiency of the device could be ascribed to the enhanced absorption and optimized domain size in the L(TPA-bTV-DCN)–PC70BM blend film.     

Low-Temperature Synthesis of Solution Processable Carbon Nitride Polymers

Carbon nitride materials require high temperatures (>500 °C) for their preparation, which entails substantial energy consumption. Furthermore, the high reaction temperature limits the materials’ processability and the control over their elemental composition. Therefore, alternative synthetic pathways that operate under milder conditions are still very much sought after. In this work, we prepared semiconductive carbon nitride (CN) polymers at low temperatures (300 °C) by carrying out the thermal condensation of triaminopyrimidine and acetoguanamine under a N₂ atmosphere. These molecules are isomers: they display the same chemical formula but a different spatial distribution of their elements. X-ray photoelectron spectroscopy (XPS) experiments and electrochemical and photophysical characterization confirm that the initial spatial organization strongly determines the chemical composition and electronic structure of the materials, which, thanks to the preservation of functional groups in their surface, display excellent processability in liquid media.