Chitosan-Ag-TiO₂ films: An effective photocatalyst under visible light

Area of Science:

• Materials Science
• Environmental Chemistry
• Nanotechnology

Background:

• Developing efficient visible light-driven photocatalysts is crucial for environmental remediation.
• Chitosan, a biopolymer, offers a sustainable platform for material synthesis.
• Heterogeneous photocatalysis requires robust and easily synthesized catalytic systems.

Purpose of the Study:

• To create novel photocatalytic systems based on chitosan for degrading harmful molecules under visible light.
• To investigate the synthesis and photocatalytic activity of TiO2/Ag/AgCl/Chitosan nanocomposites.
• To explore a mild and straightforward method for producing visible light-driven photocatalysts.

Main Methods:

• Modification of chitosan thin films via silver ion chemisorption.
• In situ synthesis of titanium dioxide (TiO2) at low temperatures (100°C).
• Characterization using X-ray Diffraction (XRD), Raman spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM), X-ray Photoelectron Spectroscopy (XPS), Thermogravimetric Analysis (TGA), Gas-Solid Diffuse Reflectance (GSDR), Laser-Induced Fluorescence (LIF), and Laser-Induced Plasma (LIP).

Main Results:

• Achieved high photocatalytic activity under visible light for the degradation of o-toluidine, salicylic acid, and 4-aminomethyl benzoic acid.
• Observed the formation of silver nanoparticles (Ag NPs) and unexpected silver chloride nanoparticles (AgCl NPs).
• The TiO2/Ag/AgCl/Chitosan system was synthesized under mild conditions, avoiding high-temperature calcination.

Conclusions:

• The developed TiO2/Ag/AgCl/Chitosan system demonstrates significant potential as a visible light-driven photocatalyst.
• The facile synthesis under mild conditions makes this system promising for industrial applications.
• This approach opens new avenues for the design of efficient and sustainable photocatalytic materials for environmental remediation.