An official website of the United States government
Electrocatalysis has become an important topic in various areas of research, including chemical catalysis, environmental research, and chemical engineering. There have been a multitude of different catalysts used in the electrocatalytic reduction of CO2, which include large classes of materials such as transition metal oxide nanoparticles (TMO), transition metal nanoparticles (TMNp), carbon-based nanomaterials, and transition metal sulfides (TMS), as well as porphyrins and phthalocyanine molecules. This review is focused on the CO2 reduction reaction (CO2RR) and the main products produced using TMS nanomaterials. The main reaction products of the CO2RR include carbon monoxide (CO), formate/formic acid (HCOO−/HCOOH), methanol (CH3OH), ethanol (CH3CH2OH), methane (CH4), and ethene (C2H4). The products of the CO2RR have been linked to the type of transition metal–sulfide catalyst used in the reaction. The TMS has been shown to control the intermediate products and thus the reaction pathway. Both experimental and computational methods have been utilized to determine the CO2 binding and chemically reduced intermediates, which drive the reaction pathways for the CO2RR and are discussed in this review.
more »
« less
Cathodic Corrosion-Induced Structural Evolution of CuNi Electrocatalysts for Enhanced CO2 Reduction
ArticleCathodic Corrosion-Induced Structural Evolution of CuNi Electrocatalysts for Enhanced CO2 ReductionWenjin Sun 1,†, Bokki Min 2,†, Maoyu Wang 3, Xue Han 4, Qiang Gao 1, Sooyeon Hwang 5, Hua Zhou 3, and Huiyuan Zhu 1,2,*1 Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA2 Department of Chemical Engineering, University of Virginia, Charlottesville, VA 22904, USA3 Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA4 Department of Chemical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA5 Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA* Correspondence: kkx8js@virginia.com† These authors contributed equally to this work.Received: 22 October 2024; Revised: 25 November 2024; Accepted: 27 November 2024; Published: 4 December 2024 Abstract: The electrochemical CO2 reduction reaction (CO2RR) has attracted significant attention as a promising strategy for storing intermittent energy in chemical bonds while sustainably producing value-added chemicals and fuels. Copper-based bimetallic catalysts are particularly appealing for CO2RR due to their unique ability to generate multi-carbon products. While substantial effort has been devoted to developing new catalysts, the evolution of bimetallic systems under operational conditions remains underexplored. In this work, we synthesized a series of CuxNi1−x nanoparticles and investigated their structural evolution during CO2RR. Due to the higher oxophilicity of Ni compared to Cu, the particles tend to become Ni-enriched at the surface upon air exposure, promoting the competing hydrogen evolution reaction (HER). At negative activation potentials, cathodic corrosion has been observed in CuxNi1−x nanoparticles, leading to the significant Ni loss and the formation of irregularly shaped Cu nanoparticles with increased defects. This structural evolution, driven by cathodic corrosion, shifts the electrolysis from HER toward CO2 reduction, significantly enhancing the Faradaic efficiency of multi-carbon products (C2+).
more »
« less
- Award ID(s):
- 2332802
- PAR ID:
- 10586695
- Publisher / Repository:
- Scilight
- Date Published:
- Journal Name:
- Materials and Interfaces
- ISSN:
- 2982-2394
- Page Range / eLocation ID:
- 7
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
The structural stability of nanocatalysts during electrochemical CO2 reduction (CO2RR) is crucial for practical applications. However, highly active nanocatalysts often reconstruct under reductive conditions, requiring stabilization strategies to maintain activity. Here, we demonstrate that the N-heterocyclic carbene (NHC) polymer stabilizes Au nanowire (NW) catalysts for selective CO2 reduction to CO over a broad potential range, enabling coupling with Cu NWs for one-step tandem conversion of CO2 to C2H4. By combining the hydrophobicity of the polystyrene chain and the strong binding of NHC to Au, the polymer stabilizes Au NWs and promotes CO2RR to CO with excellent selectivity (>90%) across −0.4 V to −1.0 V (vs RHE), a significantly broader range than unmodified Au NWs (−0.5 V to −0.7 V). Stable CO2RR at negative potentials yields a high jCO of 142 A/g Au at −1.0 V. In situ ATR-IR analysis indicates that the NHC polymer regulates the water microenvironment and suppresses hydrogen evolution at high overpotential. Moreover, NHC-Au NWs maintain excellent stability during 10 h of CO2RR testing, preserving the NW morphology and catalytic performance, while unmodified NWs degrade into nanoparticles with reduced activity and selectivity. NHC-Au NWs can be coupled with Cu NWs in a flow cell to catalyze CO2RR to C2H4 with 58% efficiency and a partial current density of 70 mA/cm2 (overall C2 product efficiency of 65%). This study presents an adaptable strategy to enhance the catalyst microenvironment, ensure stability, and enable efficient tandem CO2 conversion into value-added hydrocarbons.more » « less
-
null (Ed.)This paper reports a highly active and stable nonprecious metal electrocatalyst based on bimetallic nanoscale nickel molybdenum nitride developed for the hydrogen evolution reaction (HER). A composite of 7 nm Ni 2 Mo 3 N nanoparticles grown on nickel foam (Ni 2 Mo 3 N/NF) was prepared through a simple and economical synthetic method involving one-step annealing of Ni foam, MoCl 5 , and urea without a Ni precursor. The Ni 2 Mo 3 N/NF exhibits high activity with low overpotential ( η 10 of 21.3 mV and η 100 of 123.8 mV) and excellent stability for the HER, achieving one of the best performances among state-of-the-art transition metal nitride based catalysts in alkaline media. Supporting density functional theory (DFT) calculations indicate that N sites in Ni 2 Mo 3 N with a N–Mo coordination number of four have a hydrogen adsorption energy close to that of Pt and hence may be responsible for the enhanced HER performance.more » « less
-
ArticleSize-Controlled Synthesis of Rhodium Nanocatalysts and Applications in Low-Temperature HydroformylationAndrew Lamkins 1,2, Charles J. Ward 1,2, Jeffrey T. Miller 3, Ziad Alsudairy 4, Xinle Li 4, Joseph Thuma 1,2, Ruoyu Cui 1,2, Xun Wu 1,2, Levi M. Stanley 1 and Wenyu Huang 1,2,*1 Department of Chemistry, Iowa State University, Ames, IA 50010, USA2 Ames Laboratory, U.S. Department of Energy, Ames, IA 50010, USA3 Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, USA4 Department of Chemistry, Clark Atlanta University, Atlanta, GA 30314, USA* Correspondence: whuang@iastate.eduReceived: 3 December 2024; Revised: 30 December 2024; Accepted: 3 January 2025; Published: 10 January 2025 Abstract: Controlling the size and distribution of metal nanoparticles is one of the simplest methods of tuning the catalytic properties of a material. For a nanocrystal particle, the ratio of edge-to-terrace sites can be critical in determining its catalytic activity and selectivity to desired products. To study these effects, we have developed a simple impregnation method of controlling the dispersion of rhodium atoms at the same metal loading in the range of nanoparticles less than 10 nm. Rh precursor salts are loaded onto inert SBA-15, and increasing the ratio of chloride to acetylacetonate salts improves the dispersion of rhodium atoms to form small Rh nanoparticles. Extensive characterization of the size-controlled catalysts, including XAS and in-situ CO-DRIFTS studies, has been performed to characterize the structure of Rh nanoparticles. Applying these catalysts to the hydroformylation of styrene, we observed that turnover frequency increases with decreasing particle size from 6.4 to 1.6 nm. When applied to hydroformylation reactions, we achieved a high branched product selectivity and successfully demonstrated a route to synthesizing the pain relief drug ibuprofen. This simple method can also synthesize Pt and Pd nanoparticles between 2–10 nm.more » « less
-
The development of efficient and cost-effective catalysts for hydrogen evolution reaction (HER) is crucial for the advancement of electrochemical water splitting technology. Here, we report a novel synthetic method for the preparation of single-crystalline NiCoP nanorods with tunable aspect ratios using a CO-assisted, trioctylphosphine (TOP)-mediated approach. The introduction of CO gas at different temperatures allows for the control of the nanorod growth, resulting in various aspect ratios while maintaining a hexagonal crystal structure and a composition of 1:1 Ni/Co as NiCoP. Our results demonstrate that the NiCoP nanorods with higher aspect ratios exhibit improved HER activity and stability, with the highest aspect ratio nanorods showing the lowest overpotential and Tafel slope in both acidic and alkaline media. This study highlights the importance of controlling the size and morphology of bimetallic phosphide nanoparticles to optimize their catalytic activity for HER, providing new insights into the design and optimization of nanostructured catalysts for electrochemical water splitting applications.more » « less
- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.53941/mi.2024.100007
