Low volatility substance detection by an electrochemical sensor

摘要

Low volatility substances are detected in soil, liquids and gases by carrying out several electrochemical sensor measuring cycles of applied voltage increase and decrease, determining the current difference of successive cycles and, if a cathodic current maximum occurs, determining the associated voltage value and measuring the current intensity potentiostatically over the time to saturation. An Independent claim is also included for a sensor element for detecting low volatility substances, the sensor element (1) including work electrodes (3) in the form of micro-electrodes and an electrolyte (5) in the form of a thin layer applied to the sensor element front face which is in contact with the substance to be detected. Preferred Features: The potential range in each measuring cycle extends between the hydrogen and oxygen evolution values. The detected values may be output optically or acoustically. The substance to be detected is passed by the sensor element and, when gaseous, may be pumped through a flow-through cell on the sensor element. The electrolyte is a viscous or gel-like organic and/or inorganic electrolyte.