论文部分内容阅读
本文为分析中实用而制造的镍敏化学改良电极的可行性进行了研究。这种新型化学改良电极装置是由涂有适量丁二酮肟、Ｎａｆｉｏｎ和汞膜电极组成。由于丁二酮肟易溶于乙醇，所以它容易与Ｎａｆｉｏｎ混合并形成涂层溶液。这样该涂层液就可旋转涂在玻璃碳电极上，最后在该电极上镀上汞。这种改良型电极的主要优点是抗表面活性物干扰得到改善，并且其汞膜具有较好的物理稳定性。化学改良电极的表面能通过酸洗或电化学方法得到再生。其灵敏度随预先浓缩时间延长而增大。０．１ｐｐｂ的镍经３００ｓ预先浓缩时间能够被检测出，镍的浓度在１～８ＯＰＰｂ范围内峰电流有线性关系。过量的Ａｌ、Ｇｄ、Ｃａ、Ｍｎ、Ｐｂ、Ｈｇ和Ｂｉ均不影响镍的反应，但是试验发现若ｚｈ和Ｃｕ含量超过１００倍和Ｐｄ含量超过１０倍将会对此产生干扰。干扰最严重的是二价钴，其仅仅超过一倍的含量将会影响镍的测定。然而，由于还原峰值完全独立，因此实际上用化学改良电极能对二价镍和二价钴进行同时测定。对于二价镍来说，根据各种不同的参照特料可获得其满意的准确值。
In this paper, the feasibility of analyzing nickel-sensitized chemically modified electrodes in practical applications has been studied. The new chemical modified electrode device is coated with the appropriate amount of dimethylglyoxime, Nafion and mercury film electrode composition. Since dimethylglyoxime is readily soluble in ethanol, it is easy to mix with Nafion and form a coating solution. The coating liquid is then spin coated onto the glassy carbon electrode and finally the electrode is plated with mercury. The main advantages of this modified electrode are the improved resistance to surfactant interferences and the better physical stability of the mercury film. The surface of the chemically-modified electrode can be regenerated by pickling or electrochemical methods. Its sensitivity increases with the preconcentration time. 0.1ppb of nickel pre-concentrated by 300s can be detected, the concentration of nickel in the range of 1 ~ 8OPPb peak current linear relationship. Excess amounts of Al, Gd, Ca, Mn, Pb, Hg, and Bi did not affect the nickel reaction, but the experiment found that if zh and Cu content exceeds 100 times and Pd content more than 10 times will interfere with this. The most disturbing is the price of bivalent cobalt, which more than doubled the nickel content. However, since the reduction peaks are completely independent, the simultaneous determination of divalent nickel and bivalent cobalt is practically possible with a chemically modified electrode. In the case of divalent nickel, it is possible to obtain satisfactory values for each of the different reference materials.