The electrocatalytic conversion of carbon dioxide(CO_(2))into useful fuels and chemical feedstocks is an emerging route to alleviate global warming and reduce reliance on fossil fuels.Methanol(CH_(3)OH),as one of the ...The electrocatalytic conversion of carbon dioxide(CO_(2))into useful fuels and chemical feedstocks is an emerging route to alleviate global warming and reduce reliance on fossil fuels.Methanol(CH_(3)OH),as one of the most significant and widely used liquid fuels that can be generated by CO_(2)reduction,is essential in the chemical industry.In this minireview,we unravel the origins of the selective formation of CH_(3)OH via CO_(2)reduction,including catalyst composition designs,local structure modulations,and electrolyte/catalyst interface regulations.Finally,the remaining challenges and perspectives for the CO_(2)-to-CH_(3)OH reduction are proposed.展开更多
CO_(2) electroreduction (CO_(2) ER) using renewable energy is ideal for mitigating the greenhouse effect and closing the carbon cycle. Bicarbonate (HCO_(3)−) is most commonly employed as the electrolyte anion because ...CO_(2) electroreduction (CO_(2) ER) using renewable energy is ideal for mitigating the greenhouse effect and closing the carbon cycle. Bicarbonate (HCO_(3)−) is most commonly employed as the electrolyte anion because it is known to facilitate CO_(2) ER. However, its dynamics in the electric double layer remains obscure and requires more in-depth investigation. Herein, we investigate the refined reduction process of bicarbonate by employing in situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy. By comparing the product distributions in Ar-saturated KCl and KHCO_(3) electrolytes, we confirmed CO production from HCO_(3)^(−) in the absence of an external CO_(2) source. Notably, in contrast to an electric compulsion, negatively charged HCO_(3)− anions were found to accumulate near the electrode surface. A reduction mechanism of HCO3− is proposed in that HCO3− is not adsorbed over a catalyst, but may be enriched near the electrode surface and converted to CO_(2) and react over Au and Cu electrodes. The dependence of the CO_(2) ER activity on the local HCO3− concentration was subsequently discovered, which was in turn dependent on the bulk HCO3− concentration and cathodic potential. In particular, the local HCO3− concentration was limited by the cathodic potential, leading to a plateau in the CO_(2) ER activity. The proposed mechanism provides insights into the interaction between the catalyst and the electrolyte in CO_(2) ER.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22178104,U22B20143,21838003,and 22008069)Shanghai Municipal Science and Technology Major Project,the Shanghai Scientific and Technological Innovation Project(No.22dz1205900)+1 种基金“the Fundamental Research Funds for the Central Universities”,Shanghai Rising-Star Program(No.23QA1402200)the Shanghai Sailing Program(No.20YF1410200).
文摘The electrocatalytic conversion of carbon dioxide(CO_(2))into useful fuels and chemical feedstocks is an emerging route to alleviate global warming and reduce reliance on fossil fuels.Methanol(CH_(3)OH),as one of the most significant and widely used liquid fuels that can be generated by CO_(2)reduction,is essential in the chemical industry.In this minireview,we unravel the origins of the selective formation of CH_(3)OH via CO_(2)reduction,including catalyst composition designs,local structure modulations,and electrolyte/catalyst interface regulations.Finally,the remaining challenges and perspectives for the CO_(2)-to-CH_(3)OH reduction are proposed.
基金This work is supported by the National Key Research and Development Program of China(2016YFB0600901)the National Natural Science Foundation of China(21525626,22038009,51861125104)the Program of Introducing Talents of Discipline to Universities(No.BP0618007)for financial support.
文摘CO_(2) electroreduction (CO_(2) ER) using renewable energy is ideal for mitigating the greenhouse effect and closing the carbon cycle. Bicarbonate (HCO_(3)−) is most commonly employed as the electrolyte anion because it is known to facilitate CO_(2) ER. However, its dynamics in the electric double layer remains obscure and requires more in-depth investigation. Herein, we investigate the refined reduction process of bicarbonate by employing in situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy. By comparing the product distributions in Ar-saturated KCl and KHCO_(3) electrolytes, we confirmed CO production from HCO_(3)^(−) in the absence of an external CO_(2) source. Notably, in contrast to an electric compulsion, negatively charged HCO_(3)− anions were found to accumulate near the electrode surface. A reduction mechanism of HCO3− is proposed in that HCO3− is not adsorbed over a catalyst, but may be enriched near the electrode surface and converted to CO_(2) and react over Au and Cu electrodes. The dependence of the CO_(2) ER activity on the local HCO3− concentration was subsequently discovered, which was in turn dependent on the bulk HCO3− concentration and cathodic potential. In particular, the local HCO3− concentration was limited by the cathodic potential, leading to a plateau in the CO_(2) ER activity. The proposed mechanism provides insights into the interaction between the catalyst and the electrolyte in CO_(2) ER.
