Investigations of Sensors for Detection of Hydrogen Peroxide Vapors under the Influence of UV Illumination
- PDF / 558,913 Bytes
- 8 Pages / 612 x 792 pts (letter) Page_size
- 23 Downloads / 193 Views
stigations of Sensors for Detection of Hydrogen Peroxide Vapors under the Influence of UV Illumination M. S. Aleksanyana, *, A. G. Sayuntsa, H. A. Zakaryana, V. M. Aroutiouniana, V. M. Arakelyana, and G. E. Shahnazaryana a
Yerevan State University, Yerevan, Armenia *e-mail: [email protected]
Received March 10, 2020; revised March 29, 2020; accepted April 17, 2020
Abstract—The sensitivity of gas sensors made of doped SnO2:Co metal oxide for the detection of hydrogen peroxide vapors in the environment was studied using current-voltage, frequency-capacitance, and transient characteristics. Their measurements were carried out at room temperature under the influence of ultraviolet light and without it. It is shown that the influence of ultraviolet rays on the active surface of the sensor increases the gas sensitivity of the sensor. Studies of transient characteristics have also shown that the resistance of the sensor when it is exposed to ultraviolet rays, already at room temperature, after the feeding-off of hydrogen peroxide vapors is almost completely restored. Keywords: sensor, metal oxide semiconductor, sensitivity, hydrogen peroxide vapor, ultraviolet rays DOI: 10.3103/S1068337220030032
1. INTRODUCTION H2O as the simple combination of hydrogen and oxygen is widely used in various fields of industry and medicine. Hydrogen peroxide is a colorless, odorless, slightly ‘metallic’ taste liquid. Its density is 1470 kg/m3. Hydrogen peroxide crystallizes at –0.43°C (it prone to overcooling) and decomposes at 150.2°C. It dissolves in unlimited quantities in water, forming crystalline hydrate H2O2–2H2O. Hydrogen peroxide is a good solvent, which decomposes very slowly under normal conditions. In the presence of heavy metals (Cu, Mn, Fe, Pt, etc.), their compounds and enzymes, the decomposition of hydrogen peroxide are accelerated. Тhe presence of phosphoric acid and its salts prevents the decomposition of H2O2. Since the oxidation state of oxygen in H2O2 is 1, it can be both an oxidizing agent (which is most typical) and a reducing agent. In nature, H2O2 is formed as a result of oxidative processes involving oxygen, in particular, in the cells of plants and animals. The industry produced mainly concentrated hydrogen peroxide (90–98%), and perhydrol that is sold is a 30% solution of H2O2 [1–3]. Hydrogen peroxide is used as a ‘pure substance’: an environmentally friendly oxidizing agent, a starting material for producing peroxide compounds, a polymerization initiator, an oxidizing component of rocket fuel, and also a breach of silk, wool, fur, and other materials. Hydrogen peroxide is not toxic, but concentrated solutions of H2O2 can cause burns to the skin, respiratory tract and mucous membrane. In medicine, a 3% solution of hydrogen peroxide is used as a disinfectant, sterilizing and deodorizing agent, for washing and rinsing with inflammation of the oral cavity, tonsillitis, gynecological diseases. Solutions and ointments containing H2O2 are used as bleaches in cosmetics [4–6]. In the modern technological world, accurate
Data Loading...
