石墨电极的pH响应特性研究

Study on the Response of Graphite Electrode to the pH of Aqueous Solution

本文研究了石墨电极的pH响应特性及掺入PbO,PbO_2,PbS和PVC的影响。实验证明,纯石墨压片电极在pH1～9的范围内具有良好线性响应特性,斜率为48.3mV·pH^(1-)。掺入上述杂质后的石墨电极都不如纯石墨电极的响应好。石墨电极可以制成无内参比的全固态电极。它机械强度高,耐高温高压,不受Na^+,K^+,NH_4^+,Cl^-,B_4O_7^(2-),PO_4^(3-),HPO_4^(2-)等离子的干扰。

In this paper the responses of the electrode made of graphite and graphite mixed with PbO, PbS, PbO2 and PVC to the pH of aqueous solution have been studied. The experiments show that pure graphite electrode displays good linear response in the range of pH value 1~9 with a slope of 48. 5 mV/pH. Graphite electrode mixed with above impurities does not respond so well as pure graphite electrode. Graphite electrodes can be made into all - solid state without internal reference. It has high mechanic strength, heat resistance and high pressure resistance without interference of Na+, K+, NH_4^+, Cl-, B4O_7~2 , PO_4~3, HPO_4~2.