Highly Efficient Solar Vapor Generation via a Simple Morphological Alteration of TiO<sub>2</sub> Films Grown on a Glassy Carbon Foam
Sungdo Kim, Zeeshan Tahir, M. Rashid, Joon I. Jang, Yong Soo Kim
Abstract
Effectively utilizing eco-friendly solar energy for desalination and wastewater purification has immense potential to overcome the global water crisis. Herein, we demonstrate a highly efficient solar vapor generator (SVG) developed via a simple morphological alteration, from a two-dimensional (2D) TiO2 film (TF) to one-dimensional (1D) TiO2 nanorods (TNRs) grown on a glassy carbon foam (CF). Given that evaporation is primarily a surface physical phenomenon, the 1D morphology of TNRs provides a higher evaporation surface area compared to their 2D counterpart. Additionally, the superhydrophilic nature of TNRs ensures an adequate supply of water to the evaporation surface via effective capillary action. Consequently, the 1D TNRs properly utilize photothermal heat, which results in a significant reduction in the convection heat loss. Owing to the synergistic effect of these characteristics, TNRs/CF acquires a high evaporation rate of ∼2.23 kg m–2 h–1 and an energy utilization efficiency of ∼67.1% under one sun irradiation. Moreover, the excellent stability, desalination, self-cleaning capabilities, and the facile fabrication method make TNRs/CF suitable for cost-effective, large-scale device application.