Biomass microcrystalline cellulose based solar evaporator with aligned channels for clean water and electricity co-generation

Abstract

Solar-driven interfacial evaporation co-generation (SDIE-CG) technology can effectively solve problems such as low latent heat utilization in the evaporation process, which provides a reliable solution to the problem of hydropower shortage in remote areas. Herein, we report a tea residue microcrystalline cellulose (TMCC) aerogel (abbreviated as TCA), in which TMCC is regenerated by dissolution through the co-solvent method, and microcrystalline cellulose is rearranged by the directional slow freezing technique to get a TCA with a directional aligned pore structure, resulting in a good mechanical and salt-resistant property. Due to the internal doping of carbon black particles, the TCA has an average ultra-high absorbance of 97.46 %. The evaporation rate of TCA is up to 3.066 kg m−2h−1 under 3 kW m−2 illuminations. The maximum output voltage of the TCA is 44.801 mV under 2 kW m−2 illuminations through the introduction of a suitable wind-assisted hydropower generation device. In addition, the TCA can effectively purify the wastewater containing traditional Chinese medicine, and the chemical oxygen demand (COD) value in wastewater shows a significant decrease after treatment. It is worth noting that TCA can maintain structural integrity and stable evaporation performance in saltwater under extreme pH conditions (2<pH<11), and has potential application value in water treatment and cogeneration.