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Carbon reactive capture and conversion offers a sustainable route to valuable chemicals and fuels while aiding GHG reduction. Direct electrochemical conversion of capture solutions like bicarbonate avoids the energy demands... 

A MOF-derived CoS_xcatalyst enables efficient sulfide oxidation and nitrate reduction, offering an energy-saving strategy for ammonia synthesis and pollutant remediationviabifunctional electrolysis. 

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 direct 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. These findings offer critical insights into the development of sustainable and scalable CO2 utilization technologies. 

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 direct 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. These findings offer critical insights into the development of sustainable and scalable CO2 utilization technologies. 

This study examines farmers' acceptance of green ammonia produced by upcycling waste nitrogen using renewable energy. A mail survey, targeting a random sample of crop growers in Iowa, USA, found moderately high acceptance: about 50% support green ammonia as a fertilizer and 32% support green ammonia as a fuel. Support for green hydrogen is only 17% (24% opposing), demonstrating a preference of 2nd-generation over 1st-generation technologies. Ordinal logistic regression reveals social and psychological factors affecting attitude, including income, ideology, perceived benefit, ammonia usage, trust in science and technology, personal belief in reducing waste nitrogen, and social norm. 

A paired alkaline electrolyzer with non-noble metal catalysts was developed, demonstrating higher performances of furfural oxidation on NiFe/Ni foam at the anode and hydrogen evolution on Co/MXene at the cathode under practical current densities. 

There is a growing need to develop novel technologies that reduce reactive nitrogen concentrations in wastewater streams and decrease our reliance on fossil fuel energy required to produce N-based chemicals and fertilizers. This study conducts a techno-economic analysis (TEA) and a life cycle assessment (LCA) of the electrochemical conversion of nitrate ions (NO3–) present in wastewater to hydroxylamine (NH2OH), a valuable chemical intermediate. We employ experimental data and modeling assumptions to determine NH2OH production costs and life cycle emissions for a small-scale facility (producing 1500 kg-NH2OH/day) and a large-scale facility (producing 50,000 kg-NH2OH/day) integrated into a wastewater treatment plant. The present NH2OH production costs for the small- and large-scale facilities are estimated at $6.14/kg-NH2OH and $5.37/kg-NH2OH, respectively. The parameters dominating the electrochemical reactor cost are electrolyte, separations, and fixed cost, with their values as $1.48, $0.96, and $0.53/kg. Future cost reduction projections indicate that the present NH2OH production costs for the small- and large-scale facilities can be reduced to $2.79/kg-NH2OH and $2.06/kg-NH2OH (NH2OH market price = $1.72/kg), respectively, with improvements in the sensitivity analysis parameters. LCA results indicate that the proposed electrochemical pathway to produce NH2OH has lower life cycle impacts than the conventional pathway. 

Electrocatalytic oxidative dehydrogenation (EOD) of aldehydes enables ultra-low voltage, bipolar H2 production with co-generation of carboxylic acid. Herein, we reported a simple galvanic replacement method to prepare CuM (M = Pt, Pd, Au, and Ag) bimetallic catalysts to improve the EOD of furfural to reach industrially relevant current densities. The redox potential difference between Cu/Cu2+ and a noble metal M/My+ can incorporate the noble metal on the Cu surface and enlarge its surface area. Particularly, dispersing Pt in Cu (CuPt) achieved a record-high current density of 498 mA cm–2 for bipolar H2 production at a low cell voltage of 0.6 V and a Faradaic efficiency of >80% to H2. Future research is needed to deeply understand the synergistic effects of Cu–M toward EOD of furfural, and improve the Cu–M catalyst stability, thus offering great opportunities for future distributed manufacturing of green hydrogen and carbon chemicals with practical rates and low-carbon footprints.