1-苯基-5-巯基四氮唑和苯并三氮唑在胶态银和硫化银上的阳极抑制效应

ANODIC INHIBITION OF 1-PHENYL-5-MERCAPTOTETRAZOLE AND BENZOTRIAZOLE ON COLLOIDAL PARTICLES OF SILVER AND SILVER SULPHIDE

为了研究抑制剂对银核和硫化银核的不同作用 ,本工作考察了 1 苯基 5 巯基四氮唑 (PMT)和苯并三氮唑 (BTA)作为抑制剂在银核和硫化银核上物理显影的阳极抑制和解抑制效应 .实验结果表明 :1 )PMT和BTA对Ag核和银离子过量时制得的硫化银核 ,Ag2 S(Ag) ,的显影催化活性都有不同程度的抑制作用 ,而对硫离子过量时制得的硫化银核 ,Ag2 S(S) ,无明显的抑制作用 ,这可能是由于过量硫离子在硫化银核上的吸附要强于这两种抑制剂 ;2 )S2 O32 - 或I- 离子的存在对BTA在Ag核上有解抑制作用 ,不仅可恢复甚至提高Ag核的显影催化活性 ,而对Ag2 S核的抑制作用无明显影响 ;3)与BTA不同 ,S2 O32 - 或I- 离子对PMT在Ag核上没有解抑制作用 ,对Ag2 S(Ag)核的抑制作用还稍有增强 ,而对Ag2 S(S)核稍有减弱 ;4 )银溶胶中的表面增强拉曼谱 (SERS)测量证实 :BTA在Ag核上的吸附导致Ag核显影催化活性的下降 ,加入S2 O32 - 或I- 离子后致使BTA的SERS信号消失则意味着BTA在银核表面的脱附 .

In order to investigate the different effects of inhibitors on colloidal particles of silver and silver sulphide,the anodic inhibitions of 1 phenyl 5 mercaptotetrazole (PMT) and benzotriazole (BTA) were examined by physical development catalyzed with Ag and Ag 2S particles.The results are shown as follows:1)that both PMT and BTA gave rise to inhibitions, to some extent,on Ag particles and Ag 2S(Ag) particles prepared under slight excess of silver ions,but did not give inhibitions to Ag 2S(S) particles prepared in slight excess of sulfur ions because adsorption of the excessive sulfur ions on Ag 2S particles was stronger than that of these inhibitors;2)that in the presence of S 2O 3 2- and I - ions,the inhibition of BTA on Ag was not only eliminated,but the activity of Ag particles in catalyzing the physical development was even higher than that of Ag without addition of BTA,however,S 2O 3 2- and I - ions gave no effects on the inhibition of Ag 2S particles with BTA;3)that in the case of PMT,S 2O 3 2- and I - ions were not able to eliminate the intibition of PMT on Ag particles,but slightly increased or decreased the inhibitions on Ag 2S(Ag) or Ag 2S(S),respectively;4)that the measurements of SERS(Surface Enhancement of Raman Spectrometry)confirmed that the inhibition of BTA on Ag particles resulted from the adsorption and disappearance of an inhibition of BTA in the presence of S 2O 3 2- and I - ions resulted from the desoption of BTA on Ag particles.All this means the importance of the anodic mechanism for inhibition.