Ti3C2/PVDF membrane for efficient seawater desalination based on interfacial solar heating

Huan Peng,Miaomiao Ye,Yangyi Xiao,Chenxing Li,Kehang Zhu

doi:10.2166/ws.2020.298

Abstract

Abstract The photothermal material of Ti3C2 was synthesized by etching Ti3AlC2 with hydrofluoric acid. The as-prepared Ti3C2 was deposited on a polyvinylidene fluoride (PVDF) membrane via vacuum filtration to form a Ti3C2/PVDF membrane, which was used for seawater desalination in the next step based on interfacial solar heating. The water evaporation rate of the Ti3C2/PVDF membrane could be enhanced to 0.98 kg/m2·h under 2 sun irradiance, which was 2.8 times and 5.4 times higher than that of pure water (0.35 kg/m2·h) and PVDF (0.18 kg/m2·h) respectively. The temperature difference between the two air–water interfaces with and without the Ti3C2/PVDF membrane was as high as 11.8 °C, confirming the interfacial heating behavior. The water evaporation rate under 2 sun irradiance kept mostly in the range of 0.96–0.86 kg/m2·h over 30 days under continuous operation, indicating the high stability of the Ti3C2/PVDF membrane. Finally, it was demonstrated that the typical water-quality indexes of the condensed fresh water were below the limit values of the Standards for Drinking Water Quality in China, WHO, and US EPA.

Highlights

Water shortage has become an urgent problem around the world, restricting social progress and economic development
The purposes of this study are: (i) to provide a Ti3C2/polyvinylidene fluoride (PVDF) membrane for seawater desalination based on interfacial solar heating; (ii) to examine the water quality of the condensed fresh water obtained using this technology
In order to verify whether aluminum was completely etched by HF, the crystalline structures of the Ti3C2 before and after HF etching were analyzed by X-ray diffraction

Summary

Introduction

Water shortage has become an urgent problem around the world, restricting social progress and economic development. The water evaporation rate of the Ti3C2/PVDF membrane could be enhanced to 0.98 kg/m2·h, which was 2.8 times higher than that of pure water.

Results

Conclusion