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Shahebaz S. Khan,
Shaikh Mohd. Waseem,
Nikeshkumar N. Ingle,
Kranti Zakde,
- Research Scholar, Department of Physics, School of Basic and Applied Sciences, MGM University, Chhatrapati Sambhajinagar, Maharashtra, India
- Research Scholar, Department of Physics, School of Basic and Applied Sciences, MGM University, Chhatrapati Sambhajinagar, Maharashtra, India
- Assistant Professor, Department of Physics, School of Basic and Applied Sciences, MGM University, Chhatrapati Sambhajinagar, Maharashtra, India
- Associate Professor, Department of Physics, School of Basic and Applied Sciences, MGM University, Chhatrapati Sambhajinagar, Maharashtra, India
Abstract
Graphene oxide (GO)/polyaniline (PANI) composites with varying PANI contents (20, 40, and 60 wt%) were synthesized via in-situ oxidative polymerization and systematically investigated for their structural, morphological, optical, and gas-sensing properties. X-ray diffraction (XRD) confirmed a progressive increase in interlayer spacing and partial exfoliation of GO layers with increasing PANI content, indicating intercalation-assisted hybridization. Fourier transform infrared (FTIR) spectroscopy revealed the characteristic vibrational bands of both constituents and confirmed strong interfacial interactions through hydrogen bonding and π–π stacking. Scanning electron microscopy (SEM) showed a morphological evolution from wrinkled GO sheets to a densely interconnected composite network, most pronounced for the GO/PANI–40 composition. UV–Visible spectroscopy and Tauc analysis demonstrated enhanced electronic delocalization and a systematic reduction in optical band gap from 3.10 eV for pristine GO to 2.55 eV for GO/PANI–60, reflecting extended conjugation across the GO–PANI interface. The room-temperature ammonia (NH₃) sensing performance was evaluated for all compositions. The GO/PANI–40 composite exhibited the optimal response, combining high sensitivity, rapid response–recovery kinetics (response time ≈ 35 s and recovery time ≈ 50 s), excellent selectivity toward NH₃ over interfering gases, good repeatability over successive cycles, and long-term stability retaining more than 95% of its initial response over 30 days. This superior behaviour is attributed to synergistic interfacial charge transfer, abundant adsorption sites, and efficient charge-transport pathways within the hybrid network, highlighting GO/PANI composites as promising candidates for reliable room-temperature NH₃ detection.
Keywords: GO/PANI composite, NH3 sensing, XRD, IR, SEM.
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Journal of Polymer & Composites
| Volume | 14 | |
| 04 | ||
| Received | 06/07/2026 | |
| Accepted | 28/07/2026 | |
| Published | 14/08/2026 | |
| Publication Time | 39 Days |