Morphology Dependent Conductivity and Photoconductivity of Ionic Porphyrin Crystalline Assemblies
Morphology Dependent Conductivity and Photoconductivity of Ionic Porphyrin Crystalline Assemblies
复制标题
DOI：
10.1149/2162-8777/aba409
复制
发表时间：
2020-07
影响因子：
2.2
通讯作者：
B. Borders;K. W. Hipps;U. Mazur
中科院分区：
文献类型：
--
作者：
B. Borders;K. W. Hipps;U. Mazur
考察了形态对二元离子卟啉组装体光电导性能的影响。微米到毫米大小的晶体棒和复杂的超支化结构，或层，以受控的方式通过结合化学计量的meso-tetra（4-aminophenyl）porphyrin，H2 [H2 TAPP] 2+和meso-tetra（4-sulfonatophenyl）porphyrin，[H 4 TSPP] 2−，无金属离子tectons生长。H2 TAPP：通过X射线衍射、显微镜、光谱、电导率和光电导等测试手段对H4 TSPP结构进行了表征。两种不同的H2 TAPP：H4 TSPP形貌（棒状和层片状）表现出相似的分子组织和晶体结构，但具有不同的光电性能。杆和束表现出弱的暗电导率，并成为更好地进行照明后，到四吡咯Soret和Q带。这些固体中的主要电荷载流子在光激发时是电子，并且电荷复合机制遵循单分子动力学。束还显示出一些持久的光电导性，以及在初始照明时的光电导性的长”生长”期。这两种作用都可以归因于在其生长过程中形成的束中存在缺陷。H2 TAPP：H4 TSPP绳轮的光响应比棒的光响应高.这项工作提供的证据表明，有机半导体的光电性能可以有效地调整通过控制其分子组织和生长形态。
The influence of morphology on the photoconductive properties of binary ionic porphyrin assemblies is examined. Micro-to millimeter sized crystalline rods and complex hyperbranched structures, or sheaves, were grown in a controlled manner by combining stoichiometric amounts of meso-tetra (4-aminophenyl) porphyrin, H 2 [H 2 TAPP] 2+, and meso-tetra (4-sulfonatophenyl) porphyrin,[H 4 TSPP] 2−, metal-free ionic tectons. The H 2 TAPP: H 4 TSPP structures were characterized by X-ray diffraction, microscopic methods, optical spectroscopy, conductivity and photoconductivity measurements. The two different H 2 TAPP: H 4 TSPP morphologies (rods and sheaves) exhibit similar molecular organization and crystal structure but possess different optoelectronic properties. The rods and sheaves exhibit weak dark conductivity and become more conducting upon illumination into the tetrapyroles Soret and Q bands. The primary charge carriers in these solids upon photoexcitation are electrons and the charge recombination mechanism follows monomolecular kinetics. The sheaves also display some persistent photoconductivity, as well as a long" grow in" period of the photoconductivity upon initial illumination. Both of these actions may be attributed to the presence of defects in the sheaves that form during their growth. The measured photoresponse of the H 2 TAPP: H 4 TSPP sheaves is higher than that of the rods. This work provides evidence that optoelectronic properties of organic semiconductors can be effectively tuned by controlling their molecular organization and growth morphology.