ORCID Profile
0000-0002-2817-8367
Current Organisation
The University of Auckland
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Publisher: Springer Science and Business Media LLC
Date: 11-11-2019
Publisher: Springer Science and Business Media LLC
Date: 20-12-2019
DOI: 10.1038/S41467-019-13833-8
Abstract: Producing liquid fuels such as ethanol from CO 2 , H 2 O, and renewable electricity offers a route to store sustainable energy. The search for efficient electrocatalysts for the CO 2 reduction reaction relies on tuning the adsorption strength of carbonaceous intermediates. Here, we report a complementary approach in which we utilize hydroxide and oxide doping of a catalyst surface to tune the adsorbed hydrogen on Cu. Density functional theory studies indicate that this doping accelerates water dissociation and changes the hydrogen adsorption energy on Cu. We synthesize and investigate a suite of metal-hydroxide-interface-doped-Cu catalysts, and find that the most efficient, Ce(OH) x -doped-Cu, exhibits an ethanol Faradaic efficiency of 43% and a partial current density of 128 mA cm −2 . Mechanistic studies, wherein we combine investigation of hydrogen evolution performance with the results of operando Raman spectroscopy, show that adsorbed hydrogen hydrogenates surface *HCCOH, a key intermediate whose fate determines branching to ethanol versus ethylene.
Publisher: American Chemical Society (ACS)
Date: 30-08-2018
DOI: 10.1021/JACS.8B06029
Abstract: Hydrogenation and hydrodeoxygenation are significant and distinct approaches for the conversion of biomass and biomass-derived oxygenated chemicals into high value-added chemicals and fuels. However, it remains a great challenge to synthesize catalysts that simultaneously possess excellent hydrogenation and hydrodeoxygenation performance. Herein, we report a catalyst made of isolated single-atom Ru supported on mesoporous graphitic carbon nitride (Ru
Publisher: Springer Science and Business Media LLC
Date: 16-12-2019
Publisher: Springer Science and Business Media LLC
Date: 11-02-2019
Publisher: Springer Science and Business Media LLC
Date: 23-07-2020
DOI: 10.1038/S41467-020-17499-5
Abstract: Multi-carbon alcohols such as ethanol are valued as fuels in view of their high energy density and ready transport. Unfortunately, the selectivity toward alcohols in CO 2 /CO electroreduction is diminished by ethylene production, especially when operating at high current densities ( mA cm −2 ). Here we report a metal doping approach to tune the adsorption of hydrogen at the copper surface and thereby promote alcohol production. Using density functional theory calculations, we screen a suite of transition metal dopants and find that incorporating Pd in Cu moderates hydrogen adsorption and assists the hydrogenation of C 2 intermediates, providing a means to favour alcohol production and suppress ethylene. We synthesize a Pd-doped Cu catalyst that achieves a Faradaic efficiency of 40% toward alcohols and a partial current density of 277 mA cm −2 from CO electroreduction. The activity exceeds that of prior reports by a factor of 2.
Publisher: Springer Science and Business Media LLC
Date: 29-11-2019
DOI: 10.1038/S41467-019-13190-6
Abstract: The electroreduction of C 1 feedgas to high-energy-density fuels provides an attractive avenue to the storage of renewable electricity. Much progress has been made to improve selectivity to C 1 and C 2 products, however, the selectivity to desirable high-energy-density C 3 products remains relatively low. We reason that C 3 electrosynthesis relies on a higher-order reaction pathway that requires the formation of multiple carbon-carbon (C-C) bonds, and thus pursue a strategy explicitly designed to couple C 2 with C 1 intermediates. We develop an approach wherein neighboring copper atoms having distinct electronic structures interact with two adsorbates to catalyze an asymmetric reaction. We achieve a record n -propanol Faradaic efficiency (FE) of (33 ± 1)% with a conversion rate of (4.5 ± 0.1) mA cm −2 , and a record n -propanol cathodic energy conversion efficiency (EE cathodic half-cell ) of 21%. The FE and EE cathodic half-cell represent a 1.3× improvement relative to previously-published CO-to- n -propanol electroreduction reports.
Publisher: Springer Science and Business Media LLC
Date: 05-11-2018
DOI: 10.1038/S41467-018-07032-0
Abstract: The electrochemical reduction of carbon monoxide is a promising approach for the renewable production of carbon-based fuels and chemicals. Copper shows activity toward multi-carbon products from CO reduction, with reaction selectivity favoring two-carbon products however, efficient conversion of CO to higher carbon products such as n-propanol, a liquid fuel, has yet to be achieved. We hypothesize that copper adparticles, possessing a high density of under-coordinated atoms, could serve as preferential sites for n-propanol formation. Density functional theory calculations suggest that copper adparticles increase CO binding energy and stabilize two-carbon intermediates, facilitating coupling between adsorbed *CO and two-carbon intermediates to form three-carbon products. We form adparticle-covered catalysts in-situ by mediating catalyst growth with strong CO chemisorption. The new catalysts exhibit an n-propanol Faradaic efficiency of 23% from CO reduction at an n-propanol partial current density of 11 mA cm −2 .
Publisher: American Chemical Society (ACS)
Date: 02-03-2020
DOI: 10.1021/JACS.9B13347
Publisher: Springer Science and Business Media LLC
Date: 20-11-2019
DOI: 10.1038/S41586-019-1782-2
Abstract: The electrocatalytic reduction of carbon dioxide, powered by renewable electricity, to produce valuable fuels and feedstocks provides a sustainable and carbon-neutral approach to the storage of energy produced by intermittent renewable sources
Publisher: Elsevier BV
Date: 02-2022
Publisher: Springer Science and Business Media LLC
Date: 11-05-2020
Publisher: Springer Science and Business Media LLC
Date: 06-01-2020
Publisher: Springer Science and Business Media LLC
Date: 18-12-2019
Publisher: Springer Science and Business Media LLC
Date: 20-02-2020
DOI: 10.1038/S41467-020-14883-Z
Abstract: An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Publisher: Springer Science and Business Media LLC
Date: 03-08-2023
DOI: 10.1038/S41467-023-40342-6
Abstract: Electrochemical conversion of CO 2 to formic acid using Bismuth catalysts is one the most promising pathways for industrialization. However, it is still difficult to achieve high formic acid production at wide voltage intervals and industrial current densities because the Bi catalysts are often poisoned by oxygenated species. Herein, we report a Bi 3 S 2 nanowire-ascorbic acid hybrid catalyst that simultaneously improves formic acid selectivity, activity, and stability at high applied voltages. Specifically, a more than 95% faraday efficiency was achieved for the formate formation over a wide potential range above 1.0 V and at ere-level current densities. The observed excellent catalytic performance was attributable to a unique reconstruction mechanism to form more defective sites while the ascorbic acid layer further stabilized the defective sites by trapping the poisoning hydroxyl groups. When used in an all-solid-state reactor system, the newly developed catalyst achieved efficient production of pure formic acid over 120 hours at 50 mA cm –2 (200 mA cell current).
Publisher: Springer Science and Business Media LLC
Date: 03-12-2020
DOI: 10.1038/S41467-020-20004-7
Abstract: Electroreduction uses renewable energy to upgrade carbon dioxide to value-added chemicals and fuels. Renewable methane synthesized using such a route stands to be readily deployed using existing infrastructure for the distribution and utilization of natural gas. Here we design a suite of ligand-stabilized metal oxide clusters and find that these modulate carbon dioxide reduction pathways on a copper catalyst, enabling thereby a record activity for methane electroproduction. Density functional theory calculations show adsorbed hydrogen donation from clusters to copper active sites for the *CO hydrogenation pathway towards *CHO. We promote this effect via control over cluster size and composition and demonstrate the effect on metal oxides including cobalt(II), molybdenum(VI), tungsten(VI), nickel(II) and palladium(II) oxides. We report a carbon dioxide-to-methane faradaic efficiency of 60% at a partial current density to methane of 135 milli ere per square centimetre. We showcase operation over 18 h that retains a faradaic efficiency exceeding 55%.
Publisher: American Chemical Society (ACS)
Date: 08-05-2019
DOI: 10.1021/JACS.9B02945
Abstract: The electrochemical reduction of CO
Publisher: Springer Science and Business Media LLC
Date: 14-05-2021
DOI: 10.1038/S41467-021-23023-0
Abstract: Membrane electrode assembly (MEA) electrolyzers offer a means to scale up CO 2 -to-ethylene electroconversion using renewable electricity and close the anthropogenic carbon cycle. To date, excessive CO 2 coverage at the catalyst surface with limited active sites in MEA systems interferes with the carbon-carbon coupling reaction, diminishing ethylene production. With the aid of density functional theory calculations and spectroscopic analysis, here we report an oxide modulation strategy in which we introduce silica on Cu to create active Cu-SiO x interface sites, decreasing the formation energies of OCOH* and OCCOH*—key intermediates along the pathway to ethylene formation. We then synthesize the Cu-SiO x catalysts using one-pot coprecipitation and integrate the catalyst in a MEA electrolyzer. By tuning the CO 2 concentration, the Cu-SiO x catalyst based MEA electrolyzer shows high ethylene Faradaic efficiencies of up to 65% at high ethylene current densities of up to 215 mA cm −2 and features sustained operation over 50 h.
Publisher: American Chemical Society (ACS)
Date: 28-01-2020
DOI: 10.1021/JACS.9B12445
Abstract: The electroreduction of carbon dioxide (CO
Publisher: American Chemical Society (ACS)
Date: 09-08-2022
DOI: 10.1021/JACS.2C03982
Publisher: American Chemical Society (ACS)
Date: 29-07-2022
DOI: 10.1021/JACS.2C01044
Abstract: The carbon-carbon (C-C) bond formation is essential for the electroconversion of CO
Publisher: American Chemical Society (ACS)
Date: 14-08-2020
Publisher: American Chemical Society (ACS)
Date: 03-01-2023
Publisher: Springer Science and Business Media LLC
Date: 22-10-2019
DOI: 10.1038/S41467-019-12788-0
Abstract: The upgrading of CO 2 /CO feedstocks to higher-value chemicals via energy-efficient electrochemical processes enables carbon utilization and renewable energy storage. Substantial progress has been made to improve performance at the cathodic side whereas less progress has been made on improving anodic electro-oxidation reactions to generate value. Here we report the efficient electroproduction of value-added multi-carbon dimethyl carbonate (DMC) from CO and methanol via oxidative carbonylation. We find that, compared to pure palladium controls, boron-doped palladium (Pd-B) tunes the binding strength of intermediates along this reaction pathway and favors DMC formation. We implement this doping strategy and report the selective electrosynthesis of DMC experimentally. We achieve a DMC Faradaic efficiency of 83 ± 5%, fully a 3x increase in performance compared to the corresponding pure Pd electrocatalyst.
Publisher: Springer Science and Business Media LLC
Date: 21-08-2023
No related grants have been discovered for Ziyun Wang.