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Greenhouse gas emissions present a significant challenge to humanity, and utilizing renewable electricity to convert emitted CO₂ into value-added products offers a promising solution; however, traditional CO₂ capture and regeneration processes remain energy-intensive, restricting the overall system efficiency and decarbonization efficacy. In this study, an advanced direct reduction of captured CO₂ with large current densities for formate electrosynthesis was demonstrated without the need for CO₂ regeneration or compression. The bismuth nanosheet (DRM-BiNS) was synthesized by direct reduction of a Bi-based MOF, representing a new class of catalytic materials with a large surface area and interconnected pores, suitable for the directmore » reduction of captured CO₂. By seamlessly combining experimentation and simulation, insights into the structure-parameter-performance relation were acquired in a flow cell setting, including critical membrane-electrode distance, cell orientation, and pumping flow rate. Important flow-cell components, such as catholyte volume, electrode substrate, membrane choice, and ionomer type, were also carefully examined to enhance the cell performance. In sharp contrast to prior studies limited to current densities below 20 mA/cm² in bicarbonate-based captured CO₂ solutions, this work demonstrates a remarkable current density of 300 mA/cm² with an FE to formate comparable to the case with gas-fed CO₂ reduction. Moreover, the process sustained an FE above 50% at a high current density of 500 mA/cm². The DRM-BiNS catalyst exhibited outstanding selectivity, activity, and stability, significantly outperforming oxide-derived bismuth nanosheets (OD-BiNS) in captured CO₂ reduction. Furthermore, these findings offer critical insights into the development of sustainable and scalable CO₂ utilization technologies.« less

Carbon reactive capture and conversion offers a sustainable route to valuable chemicals and fuels while aiding Green House Gas (GHG) reduction. Direct electrochemical conversion of capture solutions like bicarbonate avoids the energy demands of conventional CO₂ regeneration. Ammonium bicarbonate (NH₄HCO₃) is particularly attractive due to its low decomposition temperature and ability to supply in situ CO₂ from dilute sources without requiring purified CO₂. Meanwhile, single-atom catalysts (SACs) with nitrogen-coordinated metal sites further enhance CO₂ reduction efficiency using Earth-abundant materials. In this study, we demonstrate a nickel single-atom catalyst (Ni-SAC)-based electrolyzer that utilizes NH₄HCO₃ as the CO₂ source, achieving significantly improvedmore » CO production performance compared to the conventional silver cathodes used in the CO₂ reduction reaction (CO₂RR) to produce CO. The Ni-SAC cathode exhibited a Faradaic efficiency of 60.1% for CO production at −200 mA cm⁻², while the silver cathode achieved a Faradaic efficiency of only 2%, likely due to ammonium-induced poisoning. Furthermore, the integration of a customized microporous layer onto the electrode significantly increased the Faradaic efficiency from 64% to 83% at −100 mA cm⁻², emphasizing the crucial role of electrode structure optimization in enhancing CO selectivity. These findings demonstrate a sustainable and economically viable strategy for green CO production directly from CO₂ capture solutions.« less

Reducing contact interface thermal and electrical resistances is in great demand across various industries, particularly in the semiconductor industry. This study introduces an approach using double-sided copper nanowire (Cu NW) arrays on copper sheets as both thermal and electrical interfacial layers, designed to effectively accommodate the topographical inconsistencies between contact surfaces. Further, experimental outcomes reveal a significant reduction in thermal contact resistance (TCR), with a value of 2.5 mm² K W^–1, thereby exceeding the efficiency of reported nanostructural thermal interface materials (TIMs). Additionally, when utilized as an electrical interfacial layer, these double-sided Cu NWs arrays dramatically reduced electrical contact resistancemore » (ECR), outperforming traditional conductive grease in applications necessitating separable bonding, though showing comparable performance to costly silver-based conductive epoxies required for permanent, inseparable bonds. The promising results of the double-sided Cu NWs arrays in reducing both TCR and ECR, confirmed by finite element simulation, highlight their substantial potential in advancing TIMs and electrical interconnection applications across various sectors.« less