固定四基酸使无金属CO2在酸和纯水中的电还原成为可能
Jia Fan1,2, Binbin Pan1,2, Jialing Wu3
1Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, China.
Angewandte Chemie (International ed. in English)
|January 2, 2024
概括
这项研究引入了一种新的方法,通过使用带正电荷的多电解质来取代酸来提高二氧化碳还原反应 (CO2 RR) 的效率. 这种方法显著提高了二氧化碳转换的产品选择性和能源效率.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 二氧化碳还原反应 (CO2 RR) 是将二氧化碳转化为有价值产品的一个有前途的途径.
- 二氧化碳RR的商业化受到高能源成本和低效率的限制,特别是在酸性条件下.
- 现有的酸系统遭受 (二) 碳酸盐沉积,降低产品选择性在高电流密度.
研究的目的:
- 制定一项战略,在酸性条件下克服二氧化碳RR的限制.
- 提高二氧化碳转化中的法拉第效率 (FE) 和能源效率 (EE).
- 在纯水供应系统中实现高效的二氧化碳RR.
主要方法:
- 通过静电相互作用将一个带正电荷的多电解质,多 (diallyldimethylammonium) 固定在石墨烯氧化物上.
- 用功能化石墨烯氧化物对白银 (Ag) 催化剂进行修改.
- 在高电流密度的酸和纯水反应器中测试改性催化剂.
主要成果:
- 在酸中的100 mA cm-2时,实现了85%的CO FE,93%的碳效率和35%的EE,用于在酸中产生CO.
- 在40°C的纯水反应堆中,在100 mA cm-2时证明了78%的CO FE和30%的EE.
- 经过修改的催化剂的性能与使用金属酸的系统相当或超过.
结论:
- 开发的战略有效地取代酸盐,减轻 (二) 碳酸盐沉积.
- 这种方法显著提高了CO2 RR性能,为高效的CO2利用提供了可行的途径.
- 这种方法在电化学二氧化碳转化中具有实际应用的潜力,甚至在纯水系统中.
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