Size-controlled synthesis of porous ZnSnO3 nanocubes for improving formaldehyde gas sensitivity

Comprehensive review of micro/nanostructured ZnSnO3: characteristics, synthesis, and diverse applications

Generally, zinc stannate (ZnSnO3) is a fascinating ternary oxide compound, which has attracted significant attention in the field of materials science due to its unique properties such high sensitivity, large specific area, non-toxic nature, and good compatibility. Furthermore, in terms of both its structure and properties, it is the most appealing category of nanoparticles. The chemical stability of ZnSnO3 under normal conditions contributes to its applicability in various fields. To date, its potential as a luminescent and photovoltaic material and application in supercapacitors, batteries, solar cells, biosensors, gas sensors, and catalysts have been extensively studied. Additionally, the efficient energy storage capacity of ZnSnO3 makes it a promising candidate for the development of energy storage systems. This review focuses on the notable progress in the structural features of ZnSnO3 nanocomposites, including the synthetic processes employed for the fabrication of various ZnSnO3 nanocomposites, their intrinsic characteristics, and their present-day uses. Specifically, we highlight the recent progress in ZnSnO3-based nanomaterials, composites, and doped materials for their utilization in Li-ion batteries, photocatalysis, gas sensors, and energy storage and conversion devices. The further exploration and understanding of the properties of ZnSnO3 will undoubtedly lead to its broader implementation and contribute to the advancement of next-generation materials and devices.

Metal Oxide Gas Sensors to Study Acetone Detection Considering Their Potential in the Diagnosis of Diabetes: A Review

Metal oxide (MOx) gas sensors have attracted considerable attention from both scientific and practical standpoints. Due to their promising characteristics for detecting toxic gases and volatile organic compounds (VOCs) compared with conventional techniques, these devices are expected to play a key role in home and public security, environmental monitoring, chemical quality control, and medicine in the near future. VOCs (e.g., acetone) are blood-borne and found in exhaled human breath as a result of certain diseases or metabolic disorders. Their measurement is considered a promising tool for noninvasive medical diagnosis, for example in diabetic patients. The conventional method for the detection of acetone vapors as a potential biomarker is based on spectrometry. However, the development of MOx-type sensors has made them increasingly attractive from a medical point of view. The objectives of this review are to assess the state of the art of the main MOx-type sensors in the detection of acetone vapors to propose future perspectives and directions that should be carried out to implement this type of sensor in the field of medicine.

Enhancement of CO gas sensing performance by Mn-doped porous ZnSnO3 microspheres

This work reports the synthesis of Mn-doped ZnSnO3 microspheres (Zn1-x Mn x SnO3) using a simple co-precipitation method with (x = 0 to 0.15) and characterized for structural, morphological, surface area, and sensing properties. X-ray diffraction (XRD) analysis revealed the face-centered cubic structure of Mn-doped ZnSnO3 samples. Brunauer-Emmett-Teller (BET) analysis demonstrated the variation in surface area from 15.229 m2 g-1 to 42.999 m2 g-1 with x = 0 to 0.15 in Zn1-x Mn x SnO3. XPS indicates the change in the defect levels by Mn doping, which plays a crucial role in chemical sensors. Indeed a significant increase (≈311.37%) in CO gas sensing response was observed in the x = 0.10 sample compared to pure ZnSnO3 with a simultaneous reduction in operating temperature from 250 to 200 °C. Moreover, remarkable enhancements in response/recovery times (≈6.6/34.1 s) were obtained in the x = 0.10 sample. The Mn-doped ZnSnO3 could be a promising candidate for CO gas sensing devices used for maintaining air quality.

Highly Sensing and Selective Performance Based on Bi-Doped Porous ZnSnO3 Nanospheres for Detection of n-Butanol

In this study, pure zinc stannate (ZnSnO₃) and bismuth (Bi)-doped ZnSnO₃ composites (Bi-ZnSnO₃) were synthesized via the in situ precipitation method, and their microstructures, morphologies, chemical components, sizes, and specific surface areas were characterized, followed by testing their gas sensing properties. The results revealed that Bi-ZnSnO₃ showed superior gas sensing properties to n-butanol gas, with an optimal operating temperature of 300 °C, which was 50 °C lower than that of pure ZnSnO₃. At this temperature, moreover, the sensitivity of Bi-ZnSnO₃ to n-butanol gas at the concentration of 100 ppm reached as high as 1450.65, which was 35.57 times that (41.01) of ammonia gas, 2.93 times that (495.09) of acetone gas, 6.02 times that (241.05) of methanol gas, 2.54 times that (571.48) of formaldehyde gas, and 2.98 times that (486.58) of ethanol gas. Bi-ZnSnO₃ had a highly repeatable performance. The total proportion of oxygen vacancies and chemi-adsorbed oxygen in Bi-ZnSnO₃ (4 wt%) was 27.72% to 32.68% higher than that of pure ZnSnO₃. Therefore, Bi-ZnSnO₃ has considerable potential in detecting n-butanol gas by virtue of its excellent gas-sensing properties.

Gas Sensors Based on Porous Ceramic Bodies of MSnO3 Perovskites (M = Ba, Ca, Zn): Formation and Sensing Properties towards Ethanol, Acetone, and Toluene Vapours

In this work, the gas-sensing functionality of porous ceramic bodies formed by the slip casting technique was studied using perovskite nanoparticles of an MSnO3 system (M = Ba, Ca, Zn) synthesized by a chemical route. The performance and reliability of the sensitive materials in the presence of different volatile organic compounds (acetone, ethanol, and toluene), and other gases (CO, H2 and NO2) were analysed. The ZnSnO3, BaSnO3, and CaSnO3 sensors showed sensitivities of 40, 16, and 8% ppm−1 towards acetone, ethanol, and toluene vapours, respectively. Good repeatability and selectivity were also observed for these gaseous analytes, as well as excellent stability for a period of 120 days. The shortest response times were recorded for the ZnSnO3 sensors (e.g., 4 s for 80 ppm acetone) with marked responses to low concentrations of acetone (1000 ppb). These results are attributed to the porosity of the sensitive materials, which favours the diffusion of gases, induces surface defects, and provides greater surface area and good sensitivity to acetone, as is seen in the case of ZnSnO3.