Bifunctional polypyrrole-based conductive paper towards simultaneous efficient solar-driven water evaporation and
Jiahong Zhang1, Pengfei Wang2, Yulian Chen1
1Guangxi Key Laboratory of Information Materials, Engineering Research Center of Electronic Information Materials and Devices, Ministry of Education, School of Material Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China. jianhuazhou@guet.edu.cn.
Abstract:
The thriving solar-driven water evaporation (SDWE) technology is considered the ideal candidate for next-generation water treatment because of its high efficiency, environment-friendliness, and low cost. The irresistible trend of diversified energy demand presents multi-functional requirements for a successful SWDE. However, the current SDWE technology rarely breaks through this technical dilemma. Here, we have designed a bifunctional polypyrrole-based capacitor to achieve water purification and energy storage. The hydrophilicity of the filter paper and the high light absorptance of polypyrrole (96.18%) promote the generation of solar steam. The evaporation rate of the PPy-200 (Polypyrrole-200) filter paper reached 1.54 kg m-2 h-1 under 1 kW m-2. Interestingly, the symmetric supercapacitor assembled with PPy-based filter paper electrodes could simultaneously realize efficient evaporation (1.94 kg m-2 h-1) and electrochemical energy storage. As a single electrode, the PPy-200 filter paper exhibited ultra-high specific capacitance (4129.50 mF cm-2) and favorable cycling stability (71.16% after 4000 cycles). More importantly, the capacitance of PP-PPy-200 (Polyvinyl alcohol/Polyethylene glycol-Polypyrrole-200) increased to 2.55 times under one sun illumination. This work not only points out a direction for solar thermal utilization, but also provides new design inspiration for high-efficiency flexible electrochemical energy storage devices.
