Enhanced NH3 gas-sensing performance of silica modified CeO2 nanostructure based sensors

Abstract

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A Highly Stable Two‐Dimensional Copper(II) Organic Framework for Proton Conduction and Ammonia Impedance Sensing

“…However,a t4 08C, the gas responses of MOF 1 to 2ppm NH 3 gas are 61, 2, and 10 %a t6 8, 85, and 98 %R H, respectively.I ng eneral,t he sensor shows excellent sensitivity at room temperature and 68 %RH, which is among the highest of the reported room-temperature sensors under 60 %R H [17] and other RHs ( Table S3 in the Supporting Information). [18,[48][49][50][51][52][53][54][55][56] What calls for special attention is that the measurement conditions of most of the previousa mmonia gas sensors are under dry air or N 2 or very low RH atmosphere; [50][51][52][53][54][55][56] the case under high RH is very rare. [49] This may be because they are based on ad ifferent sensing mechanism,i nw hich the high RH atmosphere can result in inaccurate resultso ri nactivity toward determination.…”

NiO decorated CeO2 nanostructures as room temperature isopropanol gas sensors

“…7 CeO 2 has already proved its ability in detecting various toxic gases like acetone, formaldehyde, ethanol, carbon monoxide, and ammonia. [8][9][10] Isopropanol (or isopropyl alcohol) is a colorless and ammable compound with strong odor from the family of volatile organic compounds (VOCs). 11 Isopropanol is being widely used in various applications such as lubricants, solvents, cosmetics, electronic industries for cleaning of printed circuit boards, pharmaceutical industries, household chemicals, and also in automotive eld as a petroleum additive.…”

Hydrogen gas sensor based on mesoporous In2O3 with fast response/recovery and ppb level detection limit

“…The obtained optical band-gap (Eg) of the mesoporous In2O3 based on the DRS curve is 3.44 eV. It is slightly less than the reported band-gap of 3.6 eV for the In2O3 [49,50]. Fig.…”

“…The calculated pore volume of the In2O3 sample obtained from the DFT method is 0.142 cm 3 /g, and the specific surface area from the BET method is 23.5 m 2 /g. The mesoporous structures and large specific surface areas are beneficial for the absorption/desorption of the tested gas molecules, which could contribute to the fast response/recovery and high sensitivity in hydrogen detection [49,50]. The response and recovery of the mesoporous In2O3 based sensor towards hydrogen with a concentration of 500 ppm were measured at different working temperatures and the results are shown in Fig.…”