¹ Ministry of Education, Direction of Education in AL-Anbar, Iraq

* Correspondence: othmanabad2@gmail.com; ORCID: 0000-0002-7073-7994

Green synthesis is becoming increasingly important as an environmentally friendly alternative to conventional production processes due to its growing industrial applications. In this study, aloe Vera leaf extracts were used to synthesize Fe₂O₃ nanoparticles. The micro powder was converted to nanoparticles after mixing with aloe Vera, followed by calcination and annealing. Pulsed laser deposition (PLD) was then used to deposit Fe₂O₃ nanoparticles on glass substrates at laser energies of 200 and 400 mJ. The structural, morphological, energy band gap and hydrogen sulfide sensitivity of the Fe₂O₃ nanoparticles were studied. The Fe₂O₃ nanoparticles exhibited a polycrystalline structure, and structural results derived from the Scherrer equation, AFM, and FESEM indicated that the grain size increased with increasing laser energy, resulting in densely packed, spherical-like nanoparticles. UV-Vis spectroscopy results show that the energy gap decreases from 2.3 eV to 2 eV with increasing laser power. This sensor was developed to detect H₂S gas sensitivity at different temperatures: Room temperature, 60 °C, and 100 °C. The Fe₂O₃/glass sample showed the highest sensitivity (88%) to H₂S gas at laser energy of 200 mJ and an operating temperature of 100 °C. The sensitivity of the material decreased as the laser energy increased to 400 mJ. However, the response and recovery times for both laser energies were average and decreased with increasing operating temperature.