Modified pine cone with MnO2 nanoparticles as a photoabsorber for highly efficient seawater desalination and wastewater treatment

Production of drinking water using interfacial solar steam generation (ISSG) is an efficient and sustainable technology that addresses environmental impacts and high costs associated with industrial desalination methods. In this work, a photoabsorber was fabricated for ISSG of seawater and wastewater treatment using manganese dioxide nanoparticles (MnO2 NPs) deposited on a pine cone (PC), which was named as K-PC. K-PC transports seawater or wastewater through numerous aligned microchannels to its hot surface, where the MnO2 NPs absorb a broad range of the solar spectrum in the ultraviolet to near-infrared wavelength region and convert it to heat. Under 1 sun (1 kW m(-2)), K-PC achieved an evaporation flux of 1.61 kg m(-2) h(-1) and 100% conversion efficiency. Additionally, K-PC reduced the concentration of Na+, K+, Mg2+, and Ca2+ ions in seawater and paper industry wastewater. K-PC demonstrated superior stability for ISSG during 10 evaporation-condensation cycles.

Automated summary

The production of drinking water using interfacial solar steam generation (ISSG) is an efficient technology that tackles environmental issues and high costs of industrial desalination methods. This study developed a photoabsorber, named K-PC, for ISSG of seawater and wastewater treatment, utilizing manganese dioxide nanoparticles deposited on a pine cone. The K-PC achieved a high evaporation flux and conversion efficiency, and demonstrated stability for ISSG during multiple cycles.