Synergistic effect of reduced graphene oxide and carbon black as hybrid light absorber for efficient and antifouling texture-based solar steam generator

Abstract

Efficient utilization of solar energy as the cleanest and most plentiful natural resource for drinking water is a water is as sustianble and environmental friendly approach to obviate long-standing water scarcity. Carbon-based photothermal absorbers due to broadband light absorption are very interesting in interfacial solar steam generation systems. Herein, we investigate the convenient application of reduced graphene oxide (rGO) nanosheets with carbon black (CB) nanoparticles on the cotton fabric as a flexible texture-based photothermal absorber. Polyurethane (PU) as a self-floating insulator foam was selected to manage the energy loss and preserve light converted to heat on the fabric surface. The pristine cotton fabric around the foam provides continuous water supply through the capillary forces via cellulose fibers. Our reported system exhibits maximum evaporation rates and solar-thermal conversion efficiencies of 2.05, 2.09 kg.m-2h−1 and ∼ 98, 96 % for fresh and saline water, respectively. It was observed that the synergistic effect of rGO and CB caused to a reduction in the required GO concentration as a cost effective aspect. Proper washability of the treated fabrics without any visible carbonic material emersion was confirmed owing to the acceptable recyclability of more than ten cycles. The suggested platform can be used on large scale because of the simplicity in both preparation and regeneration approaches.