Fabrication of WS₂ Thin Films via Spray Pyrolysis with Comprehensive Structural, Electrical, and Chemoresistive Analyses toward NO₂ Detection

Authors

• Chetan R. Yewale, Department of Physics and Research Centre, MGV’s MSG Arts, Science and Commerce College, Affiliated to Savitribai Phule Pune University, Malegaon, Maharashtra, India
• Satish S. Mandawade, Department of Physics and Research Centre, MGV’s MSG Arts, Science and Commerce College, Affiliated to Savitribai Phule Pune University, Malegaon, Maharashtra, India
• Rajendra V. Wagh, MVP’s Arts, Commerce and Science College, Affiliated to Savitribai Phule Pune University, Nandgaon, District Nashik, Maharashtra, India
• Umesh J. Tupe, Department of Electronic Science, Vidya-Amrut Dnyan Pratishthan's Arts, Science and Commerce College, Affiliated to Savitribai Phule Pune University, Shirsondi, District Nashik, Maharashtra, India
• Sajid Naeem, Department of Applied Sciences, Maulana Mukhtar Ahmad Nadvi Technical Campus, Affiliated to Savitribai Phule Pune University, Malegaon, Maharashtra, India
• Arun V. Patil, Department of Physics and Research Centre, MGV’s MSG Arts, Science and Commerce College, Affiliated to Savitribai Phule Pune University, Malegaon, Maharashtra, IndiaFollow

How to Cite This Article

Yewale, Chetan R.; Mandawade, Satish S.; Wagh, Rajendra V.; Tupe, Umesh J.; Naeem, Sajid; and Patil, Arun V. (2026) "Fabrication of WS₂ Thin Films via Spray Pyrolysis with Comprehensive Structural, Electrical, and Chemoresistive Analyses toward NO₂ Detection," Polytechnic Journal: Vol. 16: Iss. 1, Article 6.
DOI: https://doi.org/10.59341/2707-7799.1875

Document Type

Original Article

Abstract

Nanostructured metal sulphides are gaining attention as potential materials for resistive chemical sensors due to their high electrical conductivity and chemical stability compared to metal oxides. Among these, tungsten disulfide (WS₂), a transition metal dichalcogenide (TMD), stands out because of its distinctive electrical, optical, and mechanical properties. In this study, WS₂ thin films were synthesized on glass substrates using the spray pyrolysis technique. Structural and electrical characterizations revealed a highly porous, granular morphology with nanoparticle agglomerations, as observed through FESEM. XRD analysis confirmed a well-crystallized hexagonal WS₂ phase with an average crystallite size of 35.81 nm. The films exhibited a resistivity of 9.26 × 10⁶ Ω cm and a negative temperature coefficient of resistance (-0.00097/°C), indicating semiconducting behaviour. Gas sensing tests showed exceptional NO₂ sensitivity (94.25%) and selectivity at 60°C, with rapid response (11 s) and recovery (57 s) times, confirming WS₂’s potential for efficient low-temperature gas sensing applications.

Receive Date

30/12/2025

Revise Date

08/03/2026

Accept Date

17/03/2026

Publication Date

5-7-2026

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