Electrical equivalence of electrospray ionization with conducting and nonconducting needles
Electrical equivalence of electrospray ionization with conducting and nonconducting needles
复制标题
DOI：
10.1021/ac9902244
复制
发表时间：
1999-09-01
影响因子：
7.4
通讯作者：
Enke, CG
中科院分区：
文献类型：
--
作者：
Jackson, GS;Enke, CG
电喷雾过程的等效电路。它是一个串联电路，由电源、与溶液的电化学接触、溶液电阻（R-s）、恒流调节器组成，恒流调节器代表喷雾针孔和对电极之间的差距中的电荷分离和电荷传输过程，以及对电极处的电荷中和过程。由恒流调节器建立的电流i流过整个电路。为电路中的每个元件开发电流-电压曲线。从这些可以看出，在R-s可以忽略的情况下（电源直接连接到导电针），电流-电压曲线的形状由电荷分离过程、差距和对电极建立的恒流调节器决定。如果使用非导电针，则溶液电阻可能很大，以便与溶液的电化学接触远离尖端，使用非导电喷雾针的实验量化了溶液电阻对电流-电压曲线的影响，从V-app中减去iR（s）电压（电源电压）产生恒流调节器的电流-电压曲线。当iR（s）降是V-app的重要部分时，恒流调节器的电流-电压曲线与溶液电阻可忽略时的情况相比发生了显著变化。
An electrical equivalent circuit is derived for the electrospray process. It is a series circuit which consists of the power supply, the electrochemical contact to the solution, the solution resistance (R-s), a constant-current regulator which represents the processes of charge separation and charge transport in the gap between the spray needle aperture and the counter electrode, and charge neutralization at the counter electrode. A current i, established by the constant-current regulator flows throughout the entire circuit. Current-voltage curves are developed for each element in the circuit. From these it is shown that in the case where R-s is negligible (the power supply is connected directly to a conducting needle) the shape of the current-voltage curve is dictated by the constant-current regulator established by the charge separation process, the gap, and the counter electrode. The solution resistance may be significant if a nonconducting needle is used so that the electrochemical contact to the solution is remote from the tip, Experiments with a nonconducting spray needle quantify the effect of the solution resistance on the current-voltage curve, Subtracting the iR(s) voltage from V-app (power supply voltage) yields the current-voltage curve for the constant-current regulator. When iR(s) drop is a significant fraction of V-app, the current-voltage curve of the constant-current regulator is changed substantially from the case when the solution resistance is negligible.