Layered ZnO/MgO Nanohybrids for Photocatalytic Caffeine Degradation
Lorena Portela Brazuna1, Benjamim Sipauba Gonçalves Rubim2, Rebeca Bacani3
1Universidade Federal de São Paulo, Campus São José dos Campos Unidade Talim, Rua Talim, n° 330, Vila Nair, São José dos Campos, São Paulo Cep 12231-280, Brazil.
ACS Omega
|March 2, 2026
Summary
Researchers developed a sustainable, low-cost method for creating ZnO/MgO nanohybrids. These metal-free nanohybrids show enhanced photocatalytic activity for degrading pollutants like caffeine.
Area of Science:
- Materials Science
- Green Chemistry
- Nanotechnology
Background:
- Developing efficient and sustainable photocatalysts is crucial for environmental remediation.
- Traditional methods often rely on noble metals or harsh chemicals, posing environmental and cost concerns.
- Metal-free nanohybrids offer a promising alternative for advanced oxidation processes.
Purpose of the Study:
- To synthesize novel layered ZnO/MgO nanohybrids using a sustainable, low-cost, one-pot method.
- To investigate the structural, microstructural, and optical properties of the synthesized nanohybrids.
- To evaluate the photocatalytic efficiency of ZnO/MgO nanohybrids for caffeine degradation.
Main Methods:
- One-pot synthesis using Zn-based (glycerol-urea) and Mg-based (isopropanol-glycerol) hydrogels.
- Characterization using X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and UV-vis spectroscopy.
- Photocatalytic degradation experiments using caffeine as a model emergent pollutant.
Main Results:
- Successful formation of ZnO/MgO heterostructures with dominant nanorod morphology.
- Optimal ZM 3-1 sample exhibited high dislocation densities and engineered electronic properties.
- ZM 3-1 nanohybrid achieved 64% caffeine degradation in 120 min, nearly double the efficiency of pure ZnO.
- Demonstrated synergistic effects and accelerated reaction kinetics comparable to noble metal catalysts.
Conclusions:
- The novel green synthesis route yields high-performance, metal-free ZnO/MgO nanohybrids.
- The nanorod morphology and optimized microstructure enhance photocatalytic activity.
- These nanohybrids show significant potential for efficient pollutant degradation in advanced oxidation processes.
