Solar-driven simultaneous desalination and power generation enabled by graphene oxide nanoribbon papers

Solar-driven interfacial steam generation (SISG) has received increasing attention due to its continuous clean water generation under sunlight irradiation with high photothermal conversion efficiency. However, the inevitable waste of solar thermal energy and the poor adaptability of the photothermal material severely restrict its practical application. Herein, we report for the first time the fabrication of flexible and free-standing alkaline-earth metal ios-mediated graphene oxide nanoribbon paper (GONRs paper) by utilizing the ring-opening and cross-linking reactions of GONRs with M (Mg2+, Ca2+, Sr2+ or Ba2+). Owing to the unique structure, the as-created GONRs-M paper embraces all the desirable capabilities, including light absorption, thermal conversion, and wetting ability, and enables continuous clean water production from seawater and simulated wastewater with nearly 91.5% photothermal conversion efficiency under one solar intensity irradiation (1 kW m(-2)). In addition, complementary heat loss-induced thermoelectricity is harvested alongside SISG, ensuring simultaneous desalination and electricity production with high efficiency. This facile strategy opens an avenue for developing GONR paper-based durable steam generators, not merely for sustainable clean water production, but also for harvesting low-grade waste energy.

Automated summary

This study reports the fabrication of a flexible paper material using GONRs and alkaline-earth metal ions, which has the capabilities of photothermal conversion and wetting, and can continuously produce clean water under sunlight while recovering waste thermal energy. This method opens up new avenues for sustainable clean water production and waste heat recovery.