http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/2 Tue, 07 Apr 2026 12:59:06 GMT 2026-04-07T12:59:06Z http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/429 Influence of defect density states on NO2 gas sensing performance of Na: ZnO thin films Jasmi, K K; Johny, T. Anto; Siril, vs; Madhusoodanan, K.N. In this work, the Zn1-xNaxO (x = 0, 0.01, 0.03, and 0.05) thin film gas sensors were prepared via the sol-gel spin coating method to study the impact of sodium on structural, morphological, elemental, electrical, and gas sensing applications. Crystal structure (XRD), energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), four-probe hall measurement, and NO2 gas sensing properties were investigated to ascertain the elemental composition, morphology, defect density states, working temperature, response/recovery time, stability, selectivity, and repeatability. The 3 wt.%Na:ZnO gas sensor displays a gas-accessible structure with more oxygen vacancies, remarkable stability, and sensitivity towards NO2 gas at an optimum temperature (210 °C). A possible gas-sensing mechanism was also discussed and correlated with structural, elemental, morphological, and electrical properties. Thu, 01 Jun 2023 00:00:00 GMT http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/429 2023-06-01T00:00:00Z http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/428 Influence of oxygen vacancies on the lithium-doped Mn:ZnO thin films for improved NO2 gas-sensing applications Jasmi, K K; Johny, T. Anto; Siril, vs; Madhusoodanan, K.N. Herein, the (Zn0.97−xLixMn0.03)O ( x = 0, 0.01, 0.03, and 0.05 ) thin flms were prepared on a glass substrate via the sol–gel spin coating technique to study the infuence of lithium on Mn-doped ZnO thin flms for structural, optical, electrical, morphological, chemical, and NO2 gas-sensing applications. According to the XRD analysis, all samples display a hexagonal wurtite crystal structure. A FESEM analysis revealed that the incorporation of lithium into Mn-doped ZnO results in a smaller grain size with more voids than Mn-doped ZnO. Four-probe Hall measurements revealed the n-type conductivity on (Zn0.97−xLixMn0.03)O ( x = 0 and 0.01), whereas samples with ( x = 0.03 and 0.05 ) exhibited p-type conductivity, which was well explained. XPS and PL spectra confrmed the abundance of surface oxygen vacancies on the prepared sample. It is revealed that interaction between the defect states of lithium and manganese with inherent defect states of ZnO play a crucial role in carrier transfer for the gas-sensing process. In contrast to Mn-doped ZnO, (Zn0.96Li0.01Mn0.03)O exhibits smaller grains and a ninefold gas sensitivity (62.01) toward 75 ppm of NO2 gas at 210 °C toward 75 ppm of NO2 gas with a rapid response (30 s) and recovery (125 s) time Sun, 01 Oct 2023 00:00:00 GMT http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/428 2023-10-01T00:00:00Z http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/427 Enhanced NO2 gas sensing performance of Gd/Li co-doped ZnO thin films Jasmi, K K; Johny, T. Anto; Siril, vs; Madhusoodanan, K.N. In this paper, we demonstrate pure, Gd-doped, and Gd/Li co-doped ZnO nanostructures for NO2 gas sensing applications fabricated via the sol–gel spin coating route. The synthesized samples are examined through various characterization techniques to evaluate their physical and chemical properties. The gas sensing performance of all deposited samples was investigated at different temperatures (150–240 C) towards 75 ppm of NO2 gas. Among them, the Gd/Li codoped ZnO sample shows remarkable NO2 gas sensing performance of 55.18 at a working temperature of 210 C. Also, the gas sensitivity of Gd/Li: ZnO towards various toxic gases, including Cl2, NH3, NO, and NO2, were studied and appeared most selective towards NO2 gas. A possible NO2 gas sensing mechanism was discussed and correlated with structural, morphological, electrical, and spectral studies Mon, 01 May 2023 00:00:00 GMT http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/427 2023-05-01T00:00:00Z http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/425 Progress of 2D MXene as an Electrode Architecture for Advanced Supercapacitors: A Comprehensive Review Aravind, Anu Mini; Tomy, Merin; Kuttapan, Anupama; Aippunny, Ann Mary Kakkassery; Suryabai, Xavier Thankappan Supercapacitors, designed to store more energy and be proficient in accumulatingmore energy than conventional batteries with numerous charge−discharge cycles, have beendeveloped in response to the growing demand for energy. Transition metal carbides/nitrides calledMXenes have been the focus of researchers’ cutting-edge research in energy storage. The 2D-layeredMXenes are a hopeful contender for the electrode material due to their unique properties, such ashigh conductivity, hydrophilicity, tunable surface functional groups, better mechanical properties, andoutstanding electrochemical performance. This newly developed pseudocapacitive substance benefitselectrochemical energy storage because it is rich in interlayer ion diffusion pathways and ion storagesites. Making MXene involves etching the MAX phase precursor with suitable etchants, but differentetching methods have distinct effects on the morphology and electrochemical properties. It is anoverview of the recent progress of MXene and its structure, synthesis, and unique properties. There isa strong emphasis on the effects of shape, size, electrode design, electrolyte behavior, and othervariables on the charge storage mechanism and electrochemical performance of MXene-basedsupercapacitors. The electrochemical application of MXene and the remarkable research achievements in MXene-based compositesare an intense focus. Finally, in light of further research and potential applications, the challenges and future perspectives thatMXenes face and the prospects that MXenes present have been highlighted. Tue, 14 Nov 2023 00:00:00 GMT http://starc.stthomas.ac.in:8080/xmlui/xmlui/handle/123456789/425 2023-11-14T00:00:00Z