Investigattions on ZnO Thin Films Modified with Urea: An Approach as Ammonia Sensor.

Pure and urea-modified zinc oxide thin films are prepared using the spray pyrolysis technique on microscopic glass substrates. We have added different urea concentrations as a modifier to the zinc acetate precursor for obtaining urea-modified ZnO thin films and investigated the effect of the urea concentration on the structural, morphological, optical, and gas-sensing properties. The gas-sensing characterization of pure and urea-modified ZnO thin films is tested in the static liquid distribution technique with 25 ppm of ammonia gas at an operating temperature of 27 °C.

Facile Synthesis of Pure and Cr-Doped WO Thin Films for the Detection of Xylene at Room Temperature.

This paper focused on the preparation of pure and Cr-doped tungsten trioxide (WO) thin films using the spray pyrolysis method. Different techniques were adopted to analyze these films' structural and morphological properties. The X-ray detection analysis showed that the average crystallite size of the WO-nanostructured thin films increased as the Cr doping concentration increased.

A nanostructured Al-doped ZnO as an ultra-sensitive room-temperature ammonia gas sensor.

Novel chemi-resistive gas sensors with strong detection capabilities operating at room temperature are desirable owing to their extended cycle life, high stability, and low power consumption. The current study focuses on detecting NH at room temperature using lower gas concentrations. The co-precipitation technique was employed to produce pure and Al-doped ZnO nanoparticles, which were calcined at 300 °C for three hours.

Nanostructured Indium Oxide Thin Films as a Room Temperature Toluene Sensor.

Toluene gas is the most toxic and affects the respiratory system of humans, and thereby, its detection at lower levels is an important task. Herein, we report a room temperature-operatable indium oxide-based chemiresistive gas sensor, which detects 50 ppm toluene vapors. Nanocrystalline indium oxide (InO) films were sprayed on a pre-cleaned glass substrate using a cost-effective spray pyrolysis method at different substrate temperatures in the range of 350-500 °C.