[The enhanced mechanism of Cl- to SERS in silver colloid].

: The SERS is enhanced when KCl is added to silver colloid and cation molecule. The hypothesis supposed that Cl- bridged between nano-silver and molecule, as a result the molecule adsorbing on nano-silver surface is promoted and the SERS is therefore enhanced. The CN- and NH3 can be better adsorbed when they are added separately to the nano-silver particles, Cl- and anion molecule. The SERS reduces when CN- and NH3 are added separately to Cl-, anion molecule and silver colloid. The result is that the CN- and NH3 are so strong that they have replaced Cl- and anion molecules. Therefore the SERS reduces. This has proved the bridge role of Cl-.