Solution and Active Site Speciation Drive Selectivity for Electrocatalytic Reactive Carbon Capture in Diethanolamine over Ni–N–C Catalysts

作者：R Dominic Ross, Yulan Han, Hui‐Yun Jeong, Jenna M Ynzunza, Robert H. Lavroff, Avishek Banerjee, Aditya Prajapati, Carlos G. Morales‐Guio, Julianna Velazquez, Anastassia N. Alexandrova, Christopher Hahn · 发表于：Journal of the American Chemical Society · 年份：2026 · DOI：10.1021/jacs.5c11791 · 被引用次数：3 · 研究领域：CO2 Reduction Techniques and Catalysts、Carbon Dioxide Capture Technologies、Carbon dioxide utilization in catalysis

High Resolution Image Download MS PowerPoint Slide Direct conversion of captured forms of carbon, or reactive carbon capture (RCC), presents an opportunity to reduce the energy intensity and cost of direct CO 2 utilization from dilute sources. While amine-based sorbents effectively capture CO 2, their use for RCC presents numerous challenges with typical pure metal catalysts used for electrochemical CO 2 reduction (CO 2 R). Here, using both theory and experiments, we find that Ni–N–C single atom catalysts are effective for RCC conversion to CO using a diethanolamine sorbent, in contrast to pure metal catalysts. Computational analysis reveals that RCC can proceed directly through direct reduction of the sorbent-CO 2 adduct or indirectly by C–N bond breaking facilitating CO 2 adsorption and subsequent reduction. We find that the latter mechanism is most prevalent at low overpotentials where we experimentally observe RCC selectivity. We also find experimentally that the rate of CO production for RCC with Ni–N–C catalysts can exceed pure bicarbonate solutions at intermediate sorbent concentration (0.1–0.5 M DEA) under dilute (10–25%) streams of CO 2 at low overpotentials. The coordination environment of Ni sites and the solution speciation influence their RCC activity, with changes in protonation to coordinating N/C atoms resulting in changing the RCC mechanism and consequent activity. In situ X-ray absorption spectroscopy and computational analysis reveal restructuring under RCC...