Browsing by Author "Lu, Yingying"

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    CO2/carbonate-mediated electrochemical water oxidation to hydrogen peroxide
    (Springer Nature, 2022) Fan, Lei; Bai, Xiaowan; Xia, Chuan; Zhang, Xiao; Zhao, Xunhua; Xia, Yang; Wu, Zhen-Yu; Lu, Yingying; Liu, Yuanyue; Wang, Haotian
    Electrochemical water oxidation reaction (WOR) to hydrogen peroxide (H2O2) via a 2e− pathway provides a sustainable H2O2 synthetic route, but is challenged by the traditional 4e− counterpart of oxygen evolution. Here we report a CO2/carbonate mediation approach to steering the WOR pathway from 4e− to 2e−. Using fluorine-doped tin oxide electrode in carbonate solutions, we achieved high H2O2 selectivity of up to 87%, and delivered unprecedented H2O2 partial currents of up to 1.3 A cm−2, which represents orders of magnitude improvement compared to literature. Molecular dynamics simulations, coupled with electron paramagnetic resonance and isotope labeling experiments, suggested that carbonate mediates the WOR pathway to H2O2 through the formation of carbonate radical and percarbonate intermediates. The high selectivity, industrial-relevant activity, and good durability open up practical opportunities for delocalized H2O2 production.
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    Electrochemical CO 2 reduction to high-concentration pure formic acid solutions in an all-solid-state reactor
    (Springer Nature, 2020) Fan, Lei; Xia, Chuan; Zhu, Peng; Lu, Yingying; Wang, Haotian
    Electrochemical CO2 reduction reaction (CO2RR) to liquid fuels is currently challenged by low product concentrations, as well as their mixture with traditional liquid electrolytes, such as KHCO3 solution. Here we report an all-solid-state electrochemical CO2RR system for continuous generation of high-purity and high-concentration formic acid vapors and solutions. The cathode and anode were separated by a porous solid electrolyte (PSE) layer, where electrochemically generated formate and proton were recombined to form molecular formic acid. The generated formic acid can be efficiently removed in the form of vapors via inert gas stream flowing through the PSE layer. Coupling with a high activity (formate partial current densities ~450 mA cm−2), selectivity (maximal Faradaic efficiency ~97%), and stability (100 hours) grain boundary-enriched bismuth catalyst, we demonstrated ultra-high concentrations of pure formic acid solutions (up to nearly 100 wt.%) condensed from generated vapors via flexible tuning of the carrier gas stream.