2025/01/01 by A. M. S. Arulanantham, S. Vinoth, R. S. Rimal Isaac +6 · 1 voice
Engineering · Materials Science · #Gas Sensing Nanomaterials and Sensors #Luminescence Properties of Advanced Materials #Quantum Dots Synthesis And Properties
paper · doi:10.1515/ntrev-2025-0232
openalex publication_date 2025/01/01 · openalex created_date 2025/12/30 · openalex updated_date 2026/07/19
Abstract In this work, an economical nebulizer spray pyrolysis (NSP) method was used to successfully deposit undoped ZnS and rare earth (RE)-doped ZnS thin films containing Ce, Nd, and Pr (at doping concentrations of 2 wt%) onto glass substrates. To examine the prepared films structural, morphological, optical, and ammonia gas sensing characteristics, a wide range of characterization tools were used. All of the doped and undoped ZnS thin films crystallized in the hexagonal wurtzite structure, with a preferred orientation along the (002) plane that corresponds to the P 6 3 mc space group. This is confirmed by XRD analysis, and there are no secondary impurity phases present. The RE-doped films, especially ZnS:Pr (2 %), showed better crystallinity among the samples. FESEM images showed a uniform surface morphology with distinct nanostructured grains. Zn, S, and RE (Ce, Nd, Pr) elements were successfully incorporated into the films, according to energy dispersive X-ray (EDX) spectroscopy. In comparison to the other samples, the ZnS:Pr film showed a slight decrease in optical bandgap and improved absorption throughout the measured spectral range, according to UV-vis absorption spectra. The photoluminescence (PL) spectra reveal a stronger broad band emission around 487 nm suggesting more number native defect sites present in the samples. Finally, the gas sensing studies showed that RE doped ZnS thin films significantly improved NH 3 detection. With a sensor response of 1,520, the 2 % ZnS:Pr film outperformed the Ce, and Nd dopants. Additionally, it performed exceptionally well in terms of humidity tolerance, guaranteeing dependable functioning in a range of environmental circumstances. Furthermore, with response and recovery times of 9.7 and 8.9 s, respectively, the ZnS:Pr sensor demonstrated its abilities as a high-performance, stable, and economical material for ambient temperature NH 3 sensing applications.