Nanocrystalline chemically modified CdIn2O4 thick films for H2S gas sensor

Electrospinning synthesis of CdIn2O4 nanofibers for ethanol detection

“…CdIn 2 O 4 is a promising material for gas sensors due to its superior properties, such as metal-like low resistivity, high transmissivity in the visible range and good reflectivity in near-IR region [3][4][5]. As for gas sensors, the advantages of CdIn 2 O 4 in quick response and fast recovery to specific gases have been reported previously [6][7][8][9]. For instance, Duan and his co-workers reported that CdIn 2 O 4 thick films prepared by a co-precipitation method were highly sensitive to Cl 2 [10].…”

“…For instance, Duan and his co-workers reported that CdIn 2 O 4 thick films prepared by a co-precipitation method were highly sensitive to Cl 2 [10]. Chaudhari et al found that CdIn 2 O 4 thick films prepared by a sol-gel method were sensitive to H 2 S [11].…”

Molybdenum and tungsten oxide based gas sensors for high temperature detection of environmentally hazardous sulfur species

“…Although the volume of the literature is remarkable, most of the works are devoted to semiconducting oxides and the operation temperatures of these sensors have been reported from only room temperature to 300 • C. One of the few papers describing sensing H 2 S at higher temperatures was completed by Dawson et al; they utilized a Cr 2-y Ti y O 3+x sensing composition for a resistive-type sensor design [18] The material demonstrated a p-type characteristic at elevated temperatures (>250 • C) and showed an increase in resistance upon exposure to H 2 S (50 ppm) within a testing range of 250-500 • C. It is the sole paper, at least to our knowledge in literature, that provided temperature desorption curves for both SO 2 and H 2 S. It was seen that H 2 S exhibited two maxima at about 150 • C and 470 • C; however, the loss of SO 2 from the surface occurred at 470 • C. It was concluded that a sensor that operates at 350 • C can be cleaned by heat treatment, and a pre-treatment will increase the sensor response of the sensor [18] Some of the other transition metal oxides demonstrated for H 2 S sensing are as follows: PdO x , WO 3 , MoO 3 , In 2 O 3 , CeO 2 , SnO 2 , TiO 2 , ZnO, CuO, CdO, and various ferrites [10,15,[19][20][21][22][23][24][25][26] A majority of these reports are based on WO 3 compositions [8,10,15,[19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] In the current work, tungstate and molybdate compositions were investigated as alternative sensing materials to the typical binary compositions for sulfur gas species at higher testing temperatures (≥600 • C). Tungstates and molybdates are known to be wide band gap oxide semiconductors (3-5 eV).…”

Nanoparticles Assembled CdIn2O4 Spheres with High Sensing Properties towards n-Butanol

“…As is well known, CdIn 2 O 4 is a typical n-type semiconductor, which is widely applied for materials of transparent conducting oxides (TCO), with a bandgap of 3.2 eV [14]. Studies on CdIn 2 O 4 exhibited gas sensing performance to formaldehyde [15,16], ethanol [14,17,18], Cl 2 [19], acetone [20], petroleum gas [21], and H 2 S [22] in nanoparticles, thin films, nanofibers, octahedrons, and so on. However, a great challenge must be overcome in order to synthesize a pure phase of CdIn 2 O 4 with controllable morphology using a simple, low-cost method.…”