Waste reutilization: Carbon foam–red mud composites with photothermal effects for wastewater purification in outdoor environments

Abstract

The problems associated with the lack of clean fresh water are well-known and expected to worsen in the coming decades owing to water scarcity, which is a global occurrence even in regions currently considered water-rich. Addressing these problems calls for a tremendous amount of research to be conducted to identify robust methods for purifying water at a lower cost and with less energy, while simultaneously minimizing the use of chemicals and their impact on the environment. Herein, we prepared photothermal/photodegradation materials based on carbon foam and red mud for use in wastewater purification on basis of waste reutilization. Owing to the coupling of the photothermal effect, adsorption properties, and photodegradation performance of these materials, wastewater samples containing various organic substances (RhB and MB solutions) and industrial heavy ions were effectively purified. We designed a practical device based on these materials for use in water purification in outdoor environments under natural sunlight. The device demonstrated satisfactory purification performance, indicating its potential practicability.