Reduced graphene oxide/TiTe2 quantum dot coated waste face mask recycled for highly efficient solar steam generation

ABSTRACT

Desalination based on solar-driven interfacial steam generation has emerged as an efficient and cost-effective solution to the freshwater crisis. However, an alternative approach needs to adopt to alleviate the freshwater crisis and environmental pollution simultaneously. The widespread use of surgical face mask during the COVID-19 pandemic introduces a new environmental concern related to face mask disposal. Herein, a solar evaporator is fabricated by coating novel TiTe2 quantum dots (QDs) decorated reduced graphene oxide (rGO) on a hydrophilic substrate derived from waste face mask to desalinate seawater with an evaporation rate and efficiency of 2.09 kg m−2 h−1 and 87.79% respectively. The presence of rGO contributes to absorb a wide range of the solar spectrum, while the quantum confinement effect of QDs confines heat at the nanoscale. The use of heat sink and extended polyurethane foam (EPE) improve heat localization by minimizing heat loss. The freshwater generated by solar evaporation satisfies the WHO drinking water standard. As a result, the proposed design may reduce environmental pollutants by recycling the waste facemask while producing freshwater using only incident solar irradiation, establishing a waste-water nexus with large-scale deployment potential.