Viologen linker as a strong electron-transfer mediator in the covalent organic framework to enhance electrocatalytic CO2 reduction,Materials Chemistry Frontiers

当前位置： X-MOL 学术 › Mater. Chem. Front. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Viologen linker as a strong electron-transfer mediator in the covalent organic framework to enhance electrocatalytic CO2 reduction
Materials Chemistry Frontiers ( IF 6.0 ) Pub Date : 2023-04-06 , DOI: 10.1039/d3qm00218g
Xin Zhang _{1,

2} , Yin-Zong Yuan _{1,

2} , Hong-Fang Li ₂ , Qiu-Jin Wu _{2,

3} , Hong-Jing Zhu _{2,

3} , Yu-Liang Dong _{1,

2} , Qiao Wu _{2,

3} , Yuan-Biao Huang _{2,

3} , Rong Cao _{2,

3,

4}

Affiliation

Covalent organic frameworks (COFs) are promising candidates for the CO₂ electroreduction reaction (CO₂RR) due to their advantages of tunable structures, abundant active sites, and strong CO₂ adsorption enrichment. However, the poor conductivities of the traditional COFs usually result in a low current density in the CO₂RR and limits their use in industrial applications. Herein, viologen units as strong electron-transfer mediators (ETMs) were inserted into the backbones of Co-porphyrin-based COF (Por(Co)-Vg-COF) nanosheets to enhance the electronic conductivity and improve the CO₂RR activity. The obtained Por(Co)-Vg-COF displayed a good conductivity of 3.7 × 10⁻⁷ S m⁻¹ and thus exhibited a very high selectivity towards CO production (>98%) in a wide range of applied potentials from −0.6 V to −0.9 V versus the reversible hydrogen electrode (RHE) in neutral aqueous solution, which surpassed all the conventional COF electrocatalysts. Moreover, Por(Co)-Vg-COF was employed as the first COF electrode in an acidic/alkaline system, and achieved a high FE_CO of up to 91% at −0.9 V versus RHE in acidic electrolyte and a current density of 251 mA cm⁻² at −1.3 V versus RHE in 1 M KOH aqueous electrolyte. This work provides a facile strategy to enhance the CO₂RR performance by improving the electronic conductivity of porous framework materials via the introduction of an ETM in their backbone.

中文翻译：

紫精连接剂作为共价有机骨架中的强电子转移介体增强电催化 CO2 还原

共价有机框架 (COF) 是 CO ₂电还原反应 (CO ₂ RR) 的有前途的候选者，因为它们具有可调结构、丰富的活性位点和强 CO ₂吸附富集等优点。_{然而，传统 COF 的导电性差通常会导致 CO 2} RR中的电流密度低，从而限制了它们在工业应用中的使用。在此，将作为强电子转移介质 (ETM) 的紫精单元插入钴卟啉基 COF (Por(Co)-Vg-COF) 纳米片的骨架中，以增强电子电导率并提高 CO 2 RR_活性。获得的 Por(Co)-Vg-COF 显示出良好的导电性，为 3.7 × 10 ^-7 S m ^-1因此，与中性水溶液中的可逆氢电极 (RHE)相比，在 -0.6 V 至 -0.9 V 的广泛应用电位范围内，对 CO 生产表现出非常高的选择性（> 98％），这超过了所有传统的 COF 电催化剂. 此外，Por(Co)-Vg-COF 被用作酸性/碱性系统中的第一个 COF 电极，并在酸性电解液和电流密度为 251 的电流密度下，在 -0.9 V vs RHE 时实现了高达 91% 的高 FE _CO mA cm ^-2在 -1.3 V与1 M KOH 水性电解质中的 RHE。这项工作提供了一种简便的策略，通过以下途径提高多孔骨架材料的电子电导率来提高 CO _{2 RR 性能}在他们的主干中引入 ETM。

更新日期：2023-04-06

点击分享查看原文

点击收藏

阅读更多本刊新发论文