Enhancing the capacity of supercapacitive swing adsorption CO 2 capture by tuning charging protocols
Enhancing the capacity of supercapacitive swing adsorption CO 2 capture by tuning charging protocols
复制标题
通过调整充电协议增强超电容变吸附CO 2 捕获能力
DOI：
10.1039/d2nr00748g
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发表时间：
2022
期刊：
影响因子：
6.7
通讯作者：
Binford T
中科院分区：
文献类型：
--
作者：
Binford T
超级电容变压吸附 (SSA) 是最近发现的一种电化学驱动的二氧化碳捕获技术，与传统方法相比，有望显着提高效率。这种方法的一个局限性是二氧化碳吸附能力相对较低，而且 SSA 的潜在分子机制仍然知之甚少，阻碍了优化。在这里，我们提出了一种用于同步电化学和气体吸附测量的新设备架构，并用它来研究充电协议对 SSA 性能的影响。我们证明，改变 SSA 器件充电电压可以显着提高性能。对暴露于气体的电极进行正充电而不是负充电会增加 CO2 吸附能力，并在充电时导致 CO2 解吸而不是吸附。我们还表明，在正值和负值之间切换电压会进一步增加二氧化碳容量。先前提出的 SSA 效应机制无法解释这些现象，因此我们提出了一种基于 CO2 衍生物质进出电极微孔运动的新机制。总的来说，这项工作增进了我们对超级电容器电化学二氧化碳吸附的了解，有可能导致设备吸收能力和效率提高。
Supercapacitive swing adsorption (SSA) is a recently discovered electrochemically driven CO2 capture technology that promises significant efficiency improvements over traditional methods. A limitation of this approach is the relatively low CO2 adsorption capacity, and the underlying molecular mechanisms of SSA remain poorly understood, hindering optimization. Here we present a new device architecture for simultaneous electrochemical and gas-adsorption measurements, and use it to investigate the effects of charging protocols on SSA performance. We show that altering the voltage applied to charge the SSA device can significantly improve performance. Charging the gas-exposed electrode positively rather than negatively increases CO2 adsorption capacity and causes CO2 desorption rather than adsorption with charging. We also show that switching the voltage between positive and negative values further increases CO2 capacity. Previously proposed mechanisms of the SSA effect fail to explain these phenomena, so we present a new mechanism based on movement of CO2-derived species into and out of electrode micropores. Overall, this work advances our knowledge of electrochemical CO2 adsorption by supercapacitors, potentially leading to devices with increased uptake capacity and efficiency.