Work

TiO2 Decorated onto Three-Dimensional Carbonized Osmanthus Fragrans Leaves for Solar-Driven Clean Water Generation

Year: 2025

Type: article

Abstract: Solar steam generation (SSG) has garnered significant attention for its potential in water purification applications. While composites with physically combined structures based on semiconductors or biomass have been developed for SSG, there remains a critical need for low-cost, high-efficiency devices. In this study, TiO2 composites exhibiting excellent stability, high solar absorption, porous microstructure, and hydrophilic surfaces were identified as effective materials for SSG and water purification for the first time. A novel SSG device was designed by decorating TiO2 onto three-dimensional carbonized Osmanthus fragrans leaves (TiO2/carbonized OFL). Compared to directly carbonized OFL (without TiO2) and Osmanthus fragrans leaves with templated TiO2 (OFL-templated TiO2), the TiO2/carbonized OFL carbon composites demonstrated enhanced solar absorption, achieving over 99% in the visible region and more than 80% in the near-infrared region. Under solar illumination of 1 kW·m−2, the TiO2/carbonized OFL device achieved a high water evaporation rate of 2.31 kg·m−2·h−1, which is 1.6 times higher than that of carbonized OFL and 3.45 times higher than OFL-templated TiO2. Additionally, the TiO2/carbonized OFL system exhibited remarkable efficiency in treating pharmaceutical wastewater, with a chemical oxygen demand (COD) removal efficiency of 98.9% and an ammonia nitrogen removal efficiency of 90.8% under solar radiation.

Source: Nanomaterials

DOI: 10.3390/nano15070504