### 生物质液流催化燃料电池运行环境优化机制分析

1. 1 清华大学深圳国际研究生院 深圳 518055
• 投稿日期:2020-09-28 发布日期:2020-12-01
• 通讯作者: 李欢
• 作者简介:
* E-mail: ; Tel.: 0755-26036105; Fax: 0755-26036105
• 基金资助:
深圳可持续发展专项(KCXFZ20200201100844824)

### Optimization Mechanism for Operational Conditions of Biomass Liquid-Catalyst Fuel Cell

Shan Jiang1, Huan Li1,*()

1. 1 Tsinghua Shenzhen International Graduate School, Shenzhen 518055, China
• Received:2020-09-28 Published:2020-12-01
• Contact: Huan Li
• Supported by:
Special Program for Sustainable Development at Shenzhen(KCXFZ20200201100844824)

Liquid-catalyst fuel cell (LCFC) is a novel device that can convert biomass to electricity directly under mild conditions, but its optimal operational parameters and corresponding mechanism have not been disclosed. In this study, the effect of anolyte pH and temperature on LCFC performance was analyzed comprehensively. Polarization curves and power density curves were measured using the linear sweep voltammetry to evaluate the power generation from LCFC. The Mo5+ concentration and total organic carbon in anolyte were measured to deduce the redox reaction between organics and heteropoly acid, and the Mo5+ concentration-absorbance standard curve was established using the potassium permanganate titration method and the ultraviolet visible spectrophotometry. The valence composition of Mo in anolyte was characterized using XPS spectra. The results demonstrated that a proper anolyte acidification significantly promoted the redox reaction between organic substrates and heteropoly acid, but an excessive acidification destroyed the structure of heteropoly acid and accordingly reduced its oxidizability. When the pH of anolyte was less than 1.5, the pH affected the power output of LCFC significantly. A moderate decrease of anolyte pH improved the power density greatly. At pH 0.86, the power density reached the maximum 14.85 mW•cm–2, which was 1.24 times higher than that without anolyte acidification. At extremely low pH, the power density deteriorated due to the decomposition of heteropoly acid and its weakened oxidizability. At the pH range of 1.5 to 7.5, the effect of pH on LCFC performance was relatively small. Moderate operational temperatures could enhance the performance of LCFC, but excessively high temperatures would dehydrate proton exchange membranes and consequently hindered proton transfer. Therefore, the temperature 80 ℃ was recommended for LCFC operation.