摘要
本文用电化学方法和电化学调制现场FTIR光谱方法研究了CN^-/pt体系的行为.对0.5mol L^(-1)NaCN+0.5mol L^(-1)NaF/pt体系,在-0.8至1.0伏(相对饱和甘汞电极)电势区内,可观测到四个红外吸收峰,位置为2076、2087—2095,2138和2170cm^(-1),分别对应于溶液中的CN^-,吸附态的CN^-,pt^(2+)-CN^-配合物及NCO^-。在此伏电势范围内,Pt电极上总存在吸附态的CN^-,其吸收峰位随电势正移而移向高波数。当电势正于0.2伏时,电极上发生了两种不可逆电化学反应,分别生成Pt(CN)_2或Pt(CN)_4和NCO^-。当电势正于0.6伏时,NCO^-发生进一步的氧化反应,生成CO_2和N_2气泡。
The behaviors of cyanide ions on platium electrode were studied using cyclic voltammetry and in-situ FTIR spectroelectrochemistry. The system was 0.5moIL(-1) NaCN +0.5moIL^(-1) NaF/Pt. Four bands near 2076, 2087—2095, 2138 and 2170 cm^(-1) were found when potential changed staircasely from -0.80 to 1.00 V(vs.SCE). These bands were attributed to CN-(2076cm^(-1)) in the solution, adsorbed CN^-(2087-2095 cm^(-1)), complex compound Pt(CN)_4^(2-) and/or Pt(CN)_2(2138 cm^(-1)) and solution species NCO^- (2170cm^(-1)), respectively.The band near 2087cm^(-1) for adsorbed CN-showed blue shift with increasing potential. The experiment results showed that the adsorbed CN^- existed over the whole potential range studied. Two electrochemical reactions were observed as potential was made more positive than about 0.20 V with the products being Pt(CN)_4~2 and/or Pt(CN)_2 and NCO^-.These two reactions were irreversible. Above 0.60V the oxidation of NCO^- and surface complexes, took place, generating CO_2 and N_2.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
1989年第4期409-414,共6页
Acta Physico-Chimica Sinica
基金
博士点基金
