Preparation of Gold Nanoparticles in a Layer of Gelatin Film Using Photographic Materials. VII. Acceleration of Gold Deposition by Using Ascorbic Acid

作者：Kuge Ken'ichi^*; Yu Yue; Fuma Kazumi; Ito Ryota; Sakai Tomoko

来源：Bulletin of the Chemical Society of Japan, 2011, 84(9): 947-952.

DOI：10.1246/bcsj.20110084

The preparation of gold nanoparticles using silver-salt photographic materials and a method of gold-deposition development are investigated. Although gold rapidly precipitated in the gold-deposition developer when ascorbic acid was added, gold atoms were deposited only on the exposed areas of the photographic plate when the plate was immersed in the solution. While the deposition proceeds slowly via the disproportionation reaction of gold(I) ions in the absence of ascorbic acid, the addition of ascorbic acid accelerates the deposition rate significantly and increases the photosensitivity of the photographic plate. The gold deposition is catalyzed by photolytic silver specks, called latent image specks, on silver halide grains. Absorption spectra and TEM observations suggest a broadening of the particle size distribution, and this indicates that the difference in the catalytic activities of the photolytic silver specks between the two reactions is due to the difference in the critical size of the silver specks for triggering the deposition. Because the catalysts were prepared using light, light-based control of the catalytic properties may be possible.

• 出版日期2011-9-15