Full-Spectrum Solar-Driven Photothermal Strategy Based on Oxygen-Vacancy-Engineered NiOOH@H-TiO₂ for High-Efficiency...

Area of Science:

• Materials Science
• Environmental Science
• Photocatalysis

Background:

• Solar energy utilization for pollutant removal is limited by poor light absorption and catalyst-contaminant interactions.
• Existing photocatalysts often struggle with efficiency under full solar spectrum irradiation.
• Developing effective catalysts for water purification requires enhanced light harvesting and interfacial activity.

Purpose of the Study:

• To develop a full-spectrum photothermal catalytic platform for efficient solar-driven water purification.
• To engineer commercial TiO2 with surface oxygen vacancies for improved pollutant adsorption and photothermal conversion.
• To enhance catalytic activity by incorporating NiOOH for improved charge generation and reactive oxygen species production.

Main Methods:

• Surface modification of commercial TiO2 to introduce oxygen vacancies, creating a black derivative with broadband absorption.
• Incorporation of NiOOH onto the modified TiO2 (H-TiO2) to form NiOOH@H-TiO2 composite.
• Testing the photothermal catalytic performance using Rhodamine B degradation under simulated solar irradiation.

Main Results:

• The engineered NiOOH@H-TiO2 exhibited broadband absorption and a significant photothermal effect under near-infrared irradiation.
• Achieved rapid degradation of Rhodamine B (>99% removal in 5 minutes) at a concentration of 20 ppm.
• Demonstrated excellent stability and reusability, maintaining >98% efficiency over five cycles with minimal activity loss (<2%).

Conclusions:

• The developed full-spectrum photothermal catalyst offers a generalizable strategy for solar water purification.
• Surface oxygen vacancies in TiO2 enhance pollutant binding and photothermal conversion.
• The composite material significantly accelerates pollutant degradation through combined photothermal and photocatalytic pathways.