Photochemical formation of colloidal silver: peptizing action of acetone ketyl radical

Abstract

W h e n an aqueous AgCI0,-sodium dodecylsulphate (SDS)-isopropyl alcohol (Pr' OH) solution was photolysed with 253.7 nm light, a sharp and intense absorption band of colloidal silver (A = 390-400 nm) appeared after a relatively long induction period. In contrast, t h e sharp colloidal absorption rapidly developed when an AgCI0,-SDS-acetone [(CH,),CO] solution was irradiated under t h e s a m e conditions. It has been shown by chemical analysis and TEM characterization of t h e reduced silver that some of t h e colloidal silver agglomerates formed as a result of photolysis were peptized to fine silver particles during irradiation. Acetone ketyl radical formed by excitation of (CH3),C0 with 253.7 nm light seems to have an ability to peptize colloidal agglomerate in t h e solution phase (peptizing action). A novel ' photo-acetone method' available for preparation of fine metal particles has been proposed and applied to obtain colloidal gold, copper and platinum.We have studied photochemical formation of metal particles and thin films under fairly mild condition^.'-^ In a previous paper,, we reported that colloidal silver, gold and platinum are formed by irradiation of AgClO, , HAuCl, and Na,PtCl,

Photochemical Synthesis and Multiphoton Luminescence of Monodisperse Silver Nanocrystals

“…Photochemical reduction is an attractive means of accomplishing this end, as it allows for complete mixing of the reagents before the synthesis is initiated. Whereas a number of groups have reported photochemical syntheses of silver nanoparticles [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26], in all of this previous work, the resultant nanoparticles have been polydisperse and often relatively large as well. The polydispersity of the particles produced is probably related to the fact that these syntheses involve ultraviolet exposure times of many minutes.…”

In situ time-resolved XAFS analysis of silver particle formation by photoreduction in polymer solutions

“…The mechanism of the reduction of Ag + ions and the association of Ag 0 atoms to produce metallic Ag particles has been proposed by several groups [15,17,18,[31][32][33][34][35]. Yonezawa and co-workers reported that photoirradiation of AgClO 4 precursor complex in alcohol-water solution containing sodium dodecylsulphate (SDS) resulted in the reduction of Ag + to metallic Ag 0 particles [15].…”

“…The Ag particles are stabilized by the functional groups of polymer chains, which can weakly interact with the particle surfaces and prevent from aggregating into larger particles or aggregates. Generally, the reduction of silver salts (Ag + ) to synthesize Ag particles in aqueous solutions can be achieved chemically (for example, by using sodium borohydride [11] or hydrazine [12]) or radiolytically (by using c-irradiation [13,14], UV-irradiation [15], ultrasoundirradiation [16] and so on). The rate of Ag + reduction strongly affects the particle size and their distribution of the synthesized particles.…”

Synthesis of ruthenium particles by photoreduction in polymer solutions

“…A number of groups have been involved in synthesizing metal particles by using the photochemical reduction method [8,9]. Aqueous metal particles have been previously synthesized photochemically using ketyl radicals [10][11][12][13], as photo-activators such as benzoin [10], benzophenone [11] or acetophenone [12], in aqueous * Corresponding author.…”