Electrothermally Induced Highly Responsive and Highly Selective Vanadium Oxide Hydrogen Sensor Based on Metal–Insulator Transition

Abstract

We report highly effective hydrogen gas detection based on the metal–insulator transition (MIT) by the electrothermally induced Pd-nanoparticles-decorated vanadium oxide (VO2) nanowire prepared by the efficient and size-controllable growth method originating from V2O5 thin film driven by supercooled liquid nanodroplets. By irradiating a well-defined electron beam into the nanowires, we could significantly increase the conductivity up to four times with only a modest change in the semiconductor-to-metal transition temperature (<2 °C). When exposed to trace amounts of hydrogen gas in a single nanowire configuration, the enhanced conductivity gave rise to about a two times as fast transition to metallic phase even near room temperature (∼35 °C), by reaching much faster (∼3×) a critical current density at which the self-heating initiates. Consequently, we achieved the greatly shorter response time as well as lower operating temperature and voltage for the detection of hydrogen gas in a single VO2 nanowire device, which can be attributed to the self-heating effect accelerated by the increase in the conductivity. The single nanowire sensor also shows the capability of detecting selectively hydrogen of different three gases (O2, CO, and ethylene).

Thermochromic VO2 nanorods made by sputter deposition: Growth conditions and optical modeling

“…16 The metal-insulator transition can be influenced by a variety of external parameters, and recent work have considered the effects of strain [17][18][19] and lattice misfit with the substrate, 20,21 electric field or current activation, [22][23][24][25][26][27][28][29][30][31] light irradiation, [32][33][34][35][36][37][38] ion bombardment, 39,40 and gaseous ambience. 41 Considering the wealth of possibilities to modulate the properties of VO 2 -based thin films, it is not surprising that they are discussed for a vast number of applications such as thermochromic "smart" windows for energy efficient buildings, [42][43][44][45][46][47][48][49][50] variable-thermal-emittance surfaces for thermal radiation control, 51 oscillators and switches in (opto)electronics, 25,26,34,52,53 transistors of different types, 30,54,55 microcantilevers, 56,...…”

“…41 Considering the wealth of possibilities to modulate the properties of VO 2 -based thin films, it is not surprising that they are discussed for a vast number of applications such as thermochromic "smart" windows for energy efficient buildings, [42][43][44][45][46][47][48][49][50] variable-thermal-emittance surfaces for thermal radiation control, 51 oscillators and switches in (opto)electronics, 25,26,34,52,53 transistors of different types, 30,54,55 microcantilevers, 56,57 memory elements, 58 infrared imaging devices 36 and spatial modulators for electromagnetic radiation, 37,59 (micro)bolometers, [60][61][62][63] and sensors for humidity 64 and gas. 41 It was recently realized that nanothermochromism-involving VO 2 -based nanoparticles-can entail optical properties of primary interest for energy efficient fenestration. 11,[65][66][67] Consequently it is of great importance to develop efficient methods to prepare such nanoparticles in large quantities and over extended surfaces.…”

Synthesis and conductivity properties of Gd0.8Ca0.2BaCo2O5+δ double perovskite by sol–gel combustion

“…Thus, systems composed of such TMOs can also sense external conditions and response to them either by adapting to the changes or giving warning signals. TMOs have been widely applied in several devices, such as smart switches [2], lithium-ion batteries [3][4][5], light-emitting diodes [6], storage devices [7,8] and sensors [9][10][11].…”

Unprecedented Insulator-to-Metal Transition Dynamics by Heterogeneous Catalysis in Pd-Sensitized Single Vanadium Oxide Nanowires

“…One can find the details in material properties and the parameters of the above equation in ref [63].…”