Concurrent Synthesis and Immobilization of Ag Nanoparticles over TiO<sub>2</sub> via Plasma Reduction for Photocatalytic Treatment of Methyl Blue in Water
Noor Ul Huda Altaf,
Muhammad Yasin Naz,
Shazia Shukrullah,
Abdul Ghaffar,
Muhammad Irfan,
Dominik Walczak,
Adam Głowacz,
Mater H. Mahnashi,
Saifur Rahman,
Grzegorz Królczyk,
Ali O. Alqarni,
Usama Muhammad Niazi
Affiliations
Noor Ul Huda Altaf
Department of Physics, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan
Muhammad Yasin Naz
Department of Physics, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan
Shazia Shukrullah
Department of Physics, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan
Abdul Ghaffar
Department of Physics, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan
Muhammad Irfan
Electrical Engineering Department, College of Engineering, Najran University Saudi Arabia, Najran 11001, Saudi Arabia
Dominik Walczak
Faculty of Mechanical Engineering, Opole University of Technology, 45-758 Opole, Poland
Adam Głowacz
Department of Automatic Control and Robotics, Faculty of Electrical Engineering, Automatics, Computer Science and Biomedical Engineering, AGH University of Science and Technology, 30-059 Kraków, Poland
Mater H. Mahnashi
Department of Pharmaceutical Chemistry, College of Pharmacy, Najran University, Najran 11001, Saudi Arabia
Saifur Rahman
Electrical Engineering Department, College of Engineering, Najran University Saudi Arabia, Najran 11001, Saudi Arabia
Grzegorz Królczyk
Faculty of Mechanical Engineering, Opole University of Technology, 45-758 Opole, Poland
Ali O. Alqarni
Department of Pharmaceutical Chemistry, College of Pharmacy, Najran University, Najran 11001, Saudi Arabia
Usama Muhammad Niazi
Department of Mechanical Engineering Technology, National Skills University Islamabad, Islamabad 44000, Pakistan
Pure TiO2 nanoparticles (TiO2NPs) were produced via the sol–gel method and then coated with silver nanoparticles (AgNPs) to reduce their optical band gap. The concurrent synthesis and immobilization of AgNPs over TiO2NPs was achieved through the interaction of an open-air argon plasma jet with a solution of silver nitrate/stabilizer/TiO2NPs. The one-pot plasma synthesis and coating of AgNPs over TiO2NPs is a more straightforward and environmentally friendly method than others. The plasma-produced Ag/TiO2 nanocomposites were characterized and tested for their photocatalytic potential by degrading different concentrations of methyl blue (MB) in water. The dye concentration, oxidant dose, catalyst dose, and reaction time were also optimized for MB degradation. XRD results revealed the formation of pure AgNPs, pure TiO2NPs, and Ag/TiO2 nanocomposites with an average grain size of 12.36 nm, 18.09 nm, and 15.66 nm, respectively. The immobilization of AgNPs over TiO2NPs was also checked by producing SEM and TEM images. The band gap of AgNPs, TiO2NPs, and Ag/TiO2 nanoparticles was measured about 2.58 eV, 3.36 eV, and 2.86 eV, respectively. The ultraviolet (UV) results of the nanocomposites were supportive of the degradation of synthetic dyes in the visible light spectrum. The AgNPs in the composite not only lowered the band gap but also obstructed the electron–hole recombinations. The Ag/TiO2 composite catalyst showed 90.9% degradation efficiency with a 5 ppm dye concentration after 120 min of light exposure.
