Saijo H, Shiojiri M
Department of Electronics and Information Science, Kyoto Institute of Technology, Japan.
Microsc Res Tech. 1998 Jul 15;42(2):123-38. doi: 10.1002/(SICI)1097-0029(19980715)42:2<123::AID-JEMT6>3.0.CO;2-U.
Though the cyanine dye J-aggregates carry the role to sense the exposing light in the silver halide photographic system, little research on the morphology of the aggregates in adsorption has been made with modern surface analytical methods. In this paper, we describe the size, epitaxy, multi-layered array formation, nucleation and preferential adsorption, and irregular distribution of population between particles and the segregation on a particle, of J-aggregates adsorbed on AgBr grown in gelatin. We employed cathodoluminescence microscopy, low energy high resolution scanning electron microscopy, and atomic force microscopy. Dye molecules aggregate together near the surface of AgBr and adsorb on the surface. The growth of adsorbed aggregates is controlled by the diffusion of dye molecules from the surrounding solution. The population of J-aggregates adsorbed on an AgBr particle varies from almost none to full coverage. Each aggregate is about (20-30) x (30-50) nm in size and is 2.1 nm thick for thiacarbocyanine with sodium ion, 1.04 nm for thiacarbocyanine with tosyl ion, and 0.5 nm for an oxacarbocyanine. The aggregates connect their longer edges to each other to form arrays, and the arrays build up multi-layered stacks. The arrays align parallel and segregate to form terraces. The longer edges of J-aggregates align along [210] on AgBr (100) or [632] on AgBr (111).
尽管花青染料J聚集体在卤化银照相体系中具有感知曝光光的作用，但利用现代表面分析方法对吸附过程中聚集体形态的研究却很少。在本文中，我们描述了吸附在明胶中生长的溴化银上的J聚集体的尺寸、外延、多层阵列形成、成核与优先吸附、颗粒间数量的不规则分布以及颗粒上的偏析情况。我们采用了阴极发光显微镜、低能高分辨率扫描电子显微镜和原子力显微镜。染料分子在溴化银表面附近聚集并吸附在表面上。吸附聚集体的生长受染料分子从周围溶液中的扩散控制。吸附在溴化银颗粒上的J聚集体数量从几乎没有到完全覆盖不等。每个聚集体的尺寸约为(20 - 30)×(30 - 50)nm，对于含钠离子的硫代碳菁，厚度为2.1nm；对于含甲苯磺酰离子的硫代碳菁，厚度为1.04nm；对于恶唑碳菁，厚度为0.5nm。聚集体通过其较长的边缘相互连接形成阵列，这些阵列堆积成多层堆叠。阵列平行排列并分离形成平台。J聚集体的较长边缘在溴化银(100)上沿[210]方向排列，或在溴化银(111)上沿[632]方向排列。
