摘要
用循环伏安法研究了V^vMo_(11)-V_5~vMo_7杂多阴离子在水/硝基苯界面的转移行为,观察了溶液酸度对转移行为的影响及杂多阴离子稳定存在的pH范围。钒取代的杂多阴离子稳定性较12-磷钼杂多酸显著提高,但随钒原子数增加离子稳定性降低。在“电位窗”内转移的离子主要为-4价,转移过程为扩散控制。由循环伏安实验得到了杂多阴离子的表观转移电位Δ_0~wφ~0和转移自由能ΔG_(tr)^(0,w→0)。对于不同钒数的杂多阴离子,其半波电位E_(1/2)与pH关系均可用E_(1/2)=A-37pH(mV)描述。
Electrochemical transfer behavier of the V^vMo_(11)-V_5~vMo_7 heteropolyanions at the water/nitrobenzene interface has been investigated by using cyclic voltammetry. The effect of the solution acidity on the transfer behavior and the stable pH range of heteropolyanions were observed. Mixed melybdovanadate anions are more stable than 12-molybdophosphoric acid, however, the stability of the former decreases with increasing number of vanadium atoms. The main transfer species within the 'potential window' has the negative charges of 4 and the transfer process is diffusion controled. The apparent transfer potential Δ_o^wφ~o and the free energy ΔG_(tr)^(o,w→o), for heterepolyanions can be obtained through the voltammetric data. For different anions, the E_(1/2)-pH relationship can be described as E_(1/2)=A-37 pH.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
1990年第8期801-805,共5页
Acta Chimica Sinica
基金
国家自然科学基金
