Design and engineering of ionization gas sensor based on Mn nano-flower sculptured thin film as cathode and a stainless steel ball as anode

Crystalline-to-Amorphous Phase Transformation in CuO Nanowires for Gaseous Ionization and Sensing Application

“…Field gas ionization system is capable of ionizing the gas molecules by loading a low voltage on the electrodes and is favorable for many potential applications, for example, sensors, , environmental remediation, spectrometry, − and biomedicine . Among them, ionization gas sensors have attracted extensive interest for their advantages like high selectivity and fast response/recovery. , Ionization gas sensing is substantially based on the separation of the positive and negative charges of a gas molecule. , By ionizing the target gas, a specific current–voltage characteristic can be generated as the “fingerprint” of the gas component. , The main disadvantages of traditional bulky ionization gas sensors, for example, high power consumption and risky high operation voltage, hinder their practical application. − Therefore, one-dimensional nanomaterials with ultrasharp tips, for example, carbon nanotubes, as well as ZnO, Si, or CuO nanowires (NWs), − are equipped onto the traditional macroscopic electrodes in order to lower both the operation voltage and the current. Then, intensive studies of decorating the thin film or nanoparticles have been conducted on these nanoelectrodes to further decrease the gas ionization voltages. − However, in contrast to these approaches of additional manufacturing, the study of structural evolution of these microscopic electrodes themselves during the gas ionization is still challenging, and it is worthwhile devoting effort to it, which is strongly associated with the sensing properties of current–voltage ( I – V ) characteristics, repeatability, and stability …”

MEMS-Based Ionization Gas Sensors for VOCs with Array of Nanostructured Silicon Needles

“…Further, it is argued that the ionization gas sensor with micronanoscale materials is a feasible solution to the response saturation and high operating temperature in the technical route above-mentioned . As proposed by Modi’s group and the relevant researches, ,− a typical micro ionization gas sensor (IGS) consists of a micro- or nanostructured electrode and another parallel metal electrode, which could obtain the distinct breakdown voltage ( V b ) to fingerprint the ionization characteristics of gas species under a stepwise voltage sweep. Furthermore, the discharge current in the breakdown region is used to determine the concentration of the target gas. , As for the gas-sensing parameter, V b is intended to be studied mostly in the inorganic gases and their mixtures ,, instead of organic vapors.…”

“…As proposed by Modi’s group and the relevant researches, ,− a typical micro ionization gas sensor (IGS) consists of a micro- or nanostructured electrode and another parallel metal electrode, which could obtain the distinct breakdown voltage ( V b ) to fingerprint the ionization characteristics of gas species under a stepwise voltage sweep. Furthermore, the discharge current in the breakdown region is used to determine the concentration of the target gas. , As for the gas-sensing parameter, V b is intended to be studied mostly in the inorganic gases and their mixtures ,, instead of organic vapors. The breakdown process suffering from the degradation and oxidation of electrode materials , might be less suitable for the dynamic detection of the temporal variation of target gases.…”

“…Furthermore, the discharge current in the breakdown region is used to determine the concentration of the target gas. 7,11 As for the gas-sensing parameter, V b is intended to be studied mostly in the inorganic gases and their mixtures 9,10,12 instead of organic vapors. The breakdown process suffering from the degradation and oxidation of electrode materials 13,14 might be less suitable for the dynamic detection of the temporal variation of target gases.…”

Design and engineering of Mn conical sculptured thin films as both electrodes for a gas sensor: ionization and field emission studies

“…In these devices, the physical or chemical variation of gases should be measurable by electrical or optical signals [1,2]. On these bases different mechanisms may be used for detection of gases in gas sensors which can be classified as: semiconductor (metal oxide) sensors [3,4], optical sensors [5], field-effect transistor sensors [6], oscillation sensors [7], and sensors whose performance is based on the gas electrical breakdown [8][9][10][11][12][13][14]. The latter sensors are one of the physical sensors whose response depends on the geometrical and physical conditions of the sensor and the gas.…”