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Qiu, Z. & Edvinsson, T. (2019). Direct observation of active catalyst redox states and the effect of dynamically increased crystallinity on efficient alkaline water splitting. In: : . Paper presented at spring 2019 ACS National Meeting & Exposition.
Open this publication in new window or tab >>Direct observation of active catalyst redox states and the effect of dynamically increased crystallinity on efficient alkaline water splitting
2019 (English)Conference paper, Oral presentation with published abstract (Other academic)
Abstract [en]

Given the global increase in energy demand and serious environmental pollution, hydrogen fuel is a promising energy carrier to replace traditional fossil fuels due to its zero gas emissions and high energy density by weight. Electrochemical water electrolysis with non-precious metal catalysts offers a simple and cost-effective way for high purity and large-scale hydrogen generation. The realization of hydrogen evolution, however, is hampered by the large sustainable driving potential needed above the thermodynamic requirements. Here, we report dynamically crystallinity-enhanced (DCE) NiFe layered double hydroxide (LDH) ultrathin nanosheets, leading to faster electron transfer, smooth gas release ability, and more active surface areas, resulting in markedly improved catalytic efficiency. Compared with untreated NiFe LDH, DCE NiFe LDH exhibits much lower overpotential for the cathode reaction. Under 1 M KOH aqueous electrolyte, the bi-functional DCE catalysts require only 1.48 V and 1.29 V to reach 10 and 1 mA cm-2 in two-electrode measurements without iR-compensation, corresponding to 83% and 95% electricity-to-fuel conversion efficiency with respect to the lower heating value of hydrogen. In-situ Raman spectro-electrochemistry was carried out to obtain insight into the active catalyst phases, revealing the role of Fe and Ni and their function for OER and HER, respectively. The transformation from Ni(OH)2 to γ-NiOOH was clearly observed by in-situ Raman spectroscopy under OER operation. While, the Raman features of Ni(OH)2 and FeOOH were shown under HER process. It means the function of Ni and Fe is different under OER and HER, but it is noticeable that the observed Ni and Fe species at the different applied overpotential are dominant contribution to the catalytic activity. Our results shed light on the full understanding of overall water splitting in NiFe LDH ultrathin nanosheets and developing more efficient catalysts.

National Category
Engineering and Technology Natural Sciences
Identifiers
urn:nbn:se:uu:diva-398149 (URN)
Conference
spring 2019 ACS National Meeting & Exposition
Available from: 2019-12-02 Created: 2019-12-02 Last updated: 2019-12-02
Qiu, Z., Tai, C.-W., Niklasson, G. & Edvinsson, T. (2019). Direct observation of active catalyst surface phases and the effect of dynamic self-optimization in NiFe-layered double hydroxides for alkaline water splitting. Energy & Environmental Science, 12(2), 572-581
Open this publication in new window or tab >>Direct observation of active catalyst surface phases and the effect of dynamic self-optimization in NiFe-layered double hydroxides for alkaline water splitting
2019 (English)In: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 12, no 2, p. 572-581Article in journal (Refereed) Published
Abstract [en]

Earth-abundant transition metal-based compounds are of high interest as catalysts for sustainable hydrogen fuel generation. The realization of effective electrolysis of water, however, is still limited by the requirement of a high sustainable driving potential above thermodynamic requirements. Here, we report dynamically self-optimized (DSO) NiFe layered double hydroxide (LDH) nanosheets with promising bi-functional performance. Compared with pristine NiFe LDH, DSO NiFe LDH exhibits much lower overpotential for the hydrogen evolution reaction (HER), even outperforming platinum. Under 1 M KOH aqueous electrolyte, the bi-functional DSO catalysts show an overpotential of 184 and -59 mV without iR compensation for oxygen evolution reaction (OER) and HER at 10 mA cm(-2). The material system operates at 1.48 V and 1.29 V to reach 10 and 1 mA cm(-2) in two-electrode measurements, corresponding to 83% and 95% electricity-to-fuel conversion efficiency with respect to the lower heating value of hydrogen. The material is seen to dynamically reform the active phase of the surface layer during HER and OER, where the pristine and activated catalysts are analyzed with ex situ XPS, SAED and EELS as well as with in situ Raman spectro-electrochemistry. The results show transformation into different active interfacial species during OER and HER, revealing a synergistic interplay between iron and nickel in facilitating water electrolysis.

Place, publisher, year, edition, pages
ROYAL SOC CHEMISTRY, 2019
National Category
Other Chemical Engineering
Identifiers
urn:nbn:se:uu:diva-379268 (URN)10.1039/c8ee03282c (DOI)000459741700005 ()
Funder
Swedish Energy AgencySwedish Research Council, VR-2016-03713Swedish Research Council Formas, 2016-00908Knut and Alice Wallenberg Foundation
Available from: 2019-03-18 Created: 2019-03-18 Last updated: 2019-03-29Bibliographically approved
Arvizu, M. A., Qu, H.-Y., Cindemir, U., Qiu, Z., Rojas González, E. A., Primetzhofer, D., . . . Niklasson, G. (2019). Electrochromic WO3 thin films attain unprecedented durability by potentiostatic pretreatment. Journal of Materials Chemistry A, 7(6), 2908-2918
Open this publication in new window or tab >>Electrochromic WO3 thin films attain unprecedented durability by potentiostatic pretreatment
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2019 (English)In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 7, no 6, p. 2908-2918Article in journal (Refereed) Published
Abstract [en]

Electrochromic windows and glass facades are able to impart energy efficiency jointly with indoor comfort and convenience. Long-term durability is essential for practical implementation of this technology and has recently attracted broad interest. Here we show that a simple potentiostatic pretreatment of sputterdeposited thin films of amorphous WO3-the most widely studied electrochromic material-can yield unprecedented durability for charge exchange and optical modulation under harsh electrochemical cycling in a Li-ion-conducting electrolyte and effectively evades harmful trapping of Li. The pretreatment consisted of applying a voltage of 6.0 V vs. Li/Li+ for several hours to a film backed by a transparent conducting In2O3: Sn layer. Associated compositional and structural modifications were probed by several techniques, and improved durability was associated with elemental intermixing at the WO3/ITO and ITO/glass boundaries as well as with carbonaceous solid-electrolyte interfacial layers on the WO3 films. Our work provides important new insights into long-term durability of ion-exchange-based devices.

Place, publisher, year, edition, pages
ROYAL SOC CHEMISTRY, 2019
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-378529 (URN)10.1039/c8ta09621j (DOI)000457893400054 ()
Funder
EU, European Research Council, 267234Swedish Research Council, 821-2012-5144Swedish Research Council, 2017-00646_9Swedish Foundation for Strategic Research , RIF14-0053
Available from: 2019-03-22 Created: 2019-03-22 Last updated: 2019-03-22Bibliographically approved
Bayrak Pehlivan, I., Arvizu, M. A., Qiu, Z., Niklasson, G. A. & Edvinsson, T. (2019). Impedance Spectroscopy Modeling of Nickel–Molybdenum Alloys on Porous and Flat Substrates for Applications in Water Splitting. The Journal of Physical Chemistry C, 123(39), 23890-23897
Open this publication in new window or tab >>Impedance Spectroscopy Modeling of Nickel–Molybdenum Alloys on Porous and Flat Substrates for Applications in Water Splitting
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2019 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 123, no 39, p. 23890-23897Article in journal (Refereed) Published
Abstract [en]

Hydrogen production by splitting water using electrocatalysts powered by renewable energy from solar or wind plants is one promising alternative to produce a carbon-free and sustainable fuel. Earth-abundant and nonprecious metals are, here, of interest as a replacement for scarce and expensive platinum group catalysts. Ni–Mo is a promising alternative to Pt, but the type of the substrate could ultimately affect both the initial growth conditions and the final charge transfer in the system as a whole with resistive junctions formed in the heterojunction interface. In this study, we investigated the effect of different substrates on the hydrogen evolution reaction (HER) of Ni–Mo electrocatalysts. Ni–Mo catalysts (30 atom % Ni, 70 atom % Mo) were sputtered on various substrates with different porosities and conductivities. There was no apparent morphological difference at the surface of the catalytic films sputtered on the different substrates, and the substrates were classified from microporous to flat. The electrochemical characterization was carried out with linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) in the frequency range 0.7 Hz–100 kHz. LSV measurements were carried out at direct current (DC) potentials between 200 and −400 mV vs the reversible hydrogen electrode (RHE) in 1 M NaOH encompassing the HER. The lowest overpotentials for HER were obtained for films on the nickel foam at all current densities (−157 mV vs RHE @ 10 mA cm–2), and the overpotentials increased in the order of nickel foil, carbon cloth, fluorine-doped tin oxide, and indium tin oxide glass. EIS data were fitted with two equivalent circuit models and compared for different DC potentials and different substrate morphologies and conductivities. By critical evaluation of the data from the models, the influence of the substrates on the reaction kinetics was analyzed in the high- and low-frequency regions. In the high-frequency region, a strong substrate dependence was seen and interpreted with a Schottky-type barrier, which can be rationalized as being due to a potential barrier in the material heterojunctions or a resistive substrate–film oxide/hydroxide. The results highlight the importance of substrates, the total charge transfer properties in electrocatalysis, and the relevance of different circuit components in EIS and underpin the necessity to incorporate high-conductivity, chemically inert, and work-function-matched substrate–catalysts in the catalyst system.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2019
National Category
Materials Chemistry
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-395176 (URN)10.1021/acs.jpcc.9b02714 (DOI)000489086300017 ()
Funder
EU, Horizon 2020Swedish Research Council, VR-2015-03814Swedish Research Council, VR-2016-03713
Available from: 2019-10-14 Created: 2019-10-14 Last updated: 2019-12-12Bibliographically approved
Niklasson, G., Qiu, Z., Bayrak Pehlivan, I. & Edvinsson, T. (2019). Impedance spectroscopy of water splitting reactions on nanostructured metal-based catalysts. In: Functional Materials and Nanotechnologies (FM&NT 2018): . Paper presented at 12th International Scientific Conference on Functional Materials and Nanotechnologies (FM&NT), OCT 02-05, 2018, Riga, Latvia. Institute of Physics Publishing (IOPP), Article ID 012005.
Open this publication in new window or tab >>Impedance spectroscopy of water splitting reactions on nanostructured metal-based catalysts
2019 (English)In: Functional Materials and Nanotechnologies (FM&NT 2018), Institute of Physics Publishing (IOPP), 2019, article id 012005Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

Hydrogen production by water splitting using nanomaterials as electrocatalysts is a promising route enabling replacement of fossil fuels by renewable energy sources. In particular, the development of inexpensive non-noble metal-based catalysts is necessary in order to replace currently used expensive Pt-based catalysts. We report a detailed impedance spectroscopy study of Ni-Mo and Ni-Fe based electrocatalytic materials deposited onto porous and compact substrates with different conductivities. The results were interpreted by a critical comparison with equivalent circuit models. The reaction resistance displays a strong dependence on potential and a lower substrate dependence. The impedance behaviour can also provide information on the dominating reaction mechanism. An optimized Ni-Fe based catalyst showed very promising properties for applications in water electrolysis.

Place, publisher, year, edition, pages
Institute of Physics Publishing (IOPP), 2019
Series
IOP Conference Series-Materials Science and Engineering, ISSN 1757-8981 ; 503:1
National Category
Engineering and Technology Physical Chemistry
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-369729 (URN)10.1088/1757-899X/503/1/012005 (DOI)000471150800005 ()
Conference
12th International Scientific Conference on Functional Materials and Nanotechnologies (FM&NT), OCT 02-05, 2018, Riga, Latvia
Funder
Swedish Research Council, VR-2016-03713Swedish Research Council, VR-2015-03814EU, Horizon 2020
Available from: 2018-12-17 Created: 2018-12-17 Last updated: 2020-01-08Bibliographically approved
Qiu, Z., Ma, Y. & Edvinsson, T. (2019). In operando Raman investigation of Fe doping influence on catalytic NiO intermediates for enhanced overall water splitting. Nano Energy, 66, Article ID 104118.
Open this publication in new window or tab >>In operando Raman investigation of Fe doping influence on catalytic NiO intermediates for enhanced overall water splitting
2019 (English)In: Nano Energy, ISSN 2211-2855, E-ISSN 2211-3282, Vol. 66, article id 104118Article in journal, Editorial material (Refereed) Published
Abstract [en]

Transition metal iron (Fe)-incorporated Ni oxide and oxyhydroxide compounds generally show an enhanced activity for alkaline water splitting. However, the role of Fe for this enhanced activity is not fully elucidated, especially under hydrogen evolution reaction (HER). Herein, we combine electrochemical and spectroscopic techniques to investigate the Fe doping effect on self-standing NiO nanosheets for enhanced activities for both HER and oxygen evolution reaction (OER) in overall water splitting. The results show that the presence of Fe suppresses Ni self-oxidation and adjusts the Ni–O local environment and its ability to form surface phases. In operando Raman spectroscopy is utilized to explore the active intermediates present under catalytic conditions. Apart from a slight suppression of grain size, our results show that Fe incorporation into NiO enhances in-situ formation of active layered intermediates NixFe1-xOOH with a phase transformation of FeOOH layers into γ-NiOOH layers containing Ni4+ at potentials approaching OER in contrast to undoped NiO electrodes with a dominating conversion of NiO to β-NiOOH, with persisting Ni3+. In addition, the work function on the electrode surface is reduced by 90 meV upon Fe doping, revealing a higher intrinsic Fermi-level and thus a lower requirement for added bias during HER. Together with the lower resistance for electron transport beneficial for both HER and OER, this leads to improved OER and HER efficiency upon Fe-doping. The study shows how Fe doping influences the active catalytic NiO intermediates for both HER and OER. Specifically, in operando vibrational spectroscopy utilized in parallel with electrochemical characterization can shed light on enhancement mechanisms and influence of doping for catalytic intermediates under any chosen bias at the respective electrode under full water splitting.

National Category
Other Materials Engineering
Identifiers
urn:nbn:se:uu:diva-398147 (URN)10.1016/j.nanoen.2019.104118 (DOI)000503062400038 ()
Funder
Swedish Energy AgencySwedish Research Council, 2016-00908Swedish Research Council, VR 2015-03814
Available from: 2019-12-02 Created: 2019-12-02 Last updated: 2020-01-22Bibliographically approved
Qiu, Z., Niklasson, G. & Edvinsson, T. (2019). Investigating the influence of iron on nickel oxide nanosheets for enhanced overall water splitting through in-situ Raman and impedance spectroscopy. In: : . Paper presented at The 2019 Spring Meeting of the European Materials Research Society (E-MRS).
Open this publication in new window or tab >>Investigating the influence of iron on nickel oxide nanosheets for enhanced overall water splitting through in-situ Raman and impedance spectroscopy
2019 (English)Conference paper, Oral presentation with published abstract (Other academic)
Abstract [en]

Mixed iron-nickel-based systems with tuned microstructure have recently emerged as promising non-noble electrocatalysts for alkaline water splitting. The understanding of interfacial reaction induced charge-transfer mechanisms and active phases, however, is still limited in overall water splitting. Herein, we report a detailed investigation of active surface phases and mechanisms during both the oxygen evolution (OER) and hydrogen evolution (HER) reactions in an alkaline electrolyte through in-situ Raman and impedance spectroscopy. The frequency response of electrical behavior is interpreted by a full theoretical equivalent circuit model and is related to the Raman spectra.

  The results show that the reaction resistance exhibits a strong dependence on applied bias and electrode materials in natural correlation with the reaction rate under both OER and HER process. The presence of iron (Fe) results in a less inductive feature observed in HER impedance spectroscopy, which is associated with the coverage relaxation of involved adsorbed intermediates. By in-situ Raman spectroscopy, it is clear to see that the main function of nickel (Ni) and Fe sites are dependent on the applied energy. When the Femi level shifts to more negative potentials, the hydroxyl groups are prone to adsorb on Fe3+ sites to form Fe oxyhydroxides, whereas the hydrogen groups show the tendency to adsorb (or migrate) to Ni sites, which accelerates water reduction and thus enhances HER activity. Moreover, the presence of Fe promotes the formation of high Ni valency (γ-NiOOH), leading to an improved OER catalytic performance. Our findings provide insights into the active phases formed in-situ under both the HER and OER reactions and are expected to be valuable for design strategies for efficient and earth-abundant Ni-Fe based catalytic systems.

National Category
Engineering and Technology Natural Sciences
Identifiers
urn:nbn:se:uu:diva-398144 (URN)
Conference
The 2019 Spring Meeting of the European Materials Research Society (E-MRS)
Available from: 2019-12-02 Created: 2019-12-02 Last updated: 2020-01-08
Han, Y., Qiu, Z., Nawale, G. N., Varghese, O. P., Hilborn, J., Tian, B. & Leifer, K. (2019). MicroRNA detection based on duplex-specific nuclease-assisted target recycling and gold nanoparticle/graphene oxide nanocomposite-mediated electrocatalytic amplification. Biosensors & bioelectronics, 127, 188-193
Open this publication in new window or tab >>MicroRNA detection based on duplex-specific nuclease-assisted target recycling and gold nanoparticle/graphene oxide nanocomposite-mediated electrocatalytic amplification
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2019 (English)In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 127, p. 188-193Article in journal (Refereed) Published
Abstract [en]

DNA technology based bio-responsive nanomaterials have been widely studied as promising tools for biomedical applications. Gold nanoparticles (AuNPs) and graphene oxide (GO) sheets are representative zero- and two-dimensional nanomaterials that have long been combined with DNA technology for point-of-care diagnostics. Herein, a cascade amplification system based on duplex-specific nuclease (DSN)-assisted target recycling and electrocatalytic water-splitting is demonstrated for the detection of microRNA. Target microRNAs can form DNA: RNA heteroduplexes with DNA probes on the surface of AuNPs, which can be hydrolyzed by DSN. MicroRNAs are preserved during the reaction and released into the suspension for the digestion of multiple DNA probes. After the DSN-based reaction, AuNPs are collected and mixed with GO to form AuNP/GO nanocomposite on an electrode for the following electrocatalytic amplification. The utilization of AuNP/GO nanocomposite offers large surface area, exceptional affinity to water molecules, and facilitated mass diffusion for the water-splitting reaction. For let-7b detection, the proposed biosensor achieved a limit detection of 1.5 fM in 80 min with a linear detection range of approximately four orders of magnitude. Moreover, it has the capability of discriminating non-target microRNAs containing even single-nucleotide mismatches, thus holding considerable potential for clinical diagnostics.

Keywords
Gold nanoparticles, Graphene oxide, MicroRNA detection, Electrocatalytic amplification, Duplex-specific nuclease
National Category
Analytical Chemistry Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-377203 (URN)10.1016/j.bios.2018.12.027 (DOI)000457508800026 ()30611105 (PubMedID)
Funder
Swedish Research Council, 2016-05259Knut and Alice Wallenberg FoundationEU, Horizon 2020, 713683
Available from: 2019-02-25 Created: 2019-02-25 Last updated: 2019-04-24Bibliographically approved
Qiu, Z. (2019). Transition Metal-Based Electrocatalysts for Alkaline Water Splitting and CO2 Reduction. (Doctoral dissertation). Uppsala: Acta Universitatis Upsaliensis
Open this publication in new window or tab >>Transition Metal-Based Electrocatalysts for Alkaline Water Splitting and CO2 Reduction
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

With excessive usage of fossil fuels and ever-increasing environmental issues, numerous efforts have been devoted to the development of renewable energies for the replacement of traditional fossil fuels to reduce greenhouse gas emission and realize the rapidly growing demand for global energy. Renewable energies, however, often show diurnal and seasonal variations in power output, forming a need for energy storage to meet people’s continuous energy supply. One approach is to use electrolysis and produce a fuel that can be used on demand at a later stage. A full realization of effective electricity-to-fuel conversion, however, is still limited by the large overpotential requirements as well as concerns with the usage of scarce platinum group elements. This thesis presents studies on transition metal-based electrocatalysts for alkaline water splitting and CO2 reduction, which are two technologies to produce a chemical fuel from renewable electricity. Our aim is to develop efficient, inexpensive, and robust electrocatalysts based on earth-abundant elements with high energy conversion efficiencies.

In the first part, we develop and investigate three different electrocatalysts intended for high-performance electrocatalysis of water; NiO nanoflakes (NFs) with tuneable surface morphologies, Fe doped NiO nanosheets (NSs), and self-optimized NiFe layered double hydroxide (LDH) NSs. The self-assembled NiO NFs show drastically different performance for the oxygen evolution reaction (OER). Besides the morphology effect on the catalytic property, the presence of Fe is also functional to improve the catalytic activity for both OER and hydrogen evolution reaction (HER). The NiFe LDH NSs form the most effective system for the overall catalytic performance and is dramatically improved via a dynamic self-optimization, especially for HER, where the overpotential decreases from 206 mV to 59 mV at 10 mA cm-2. In order to get insight into the interfacial reaction processes, a variety of techniques were performed to explore the underlying reasons for the catalytic improvement. Ex-situ X-ray photoelectron spectroscopy, transmission electron microscope and in-situ Raman spectroscopy were utilized to characterize and understand the oxidations states, the crystallinity and the active phases. Electrochemical impedance spectroscopy was applied to investigate the dominating reaction mechanisms during high-performance and stable electrocatalysis.

In the second part, dynamically formed CuInO2 nanoparticles were demonstrated to be high-performance electrocatalysts for CO2 reduction. In-situ Raman spectroscopy was utilized to reveal and understand the formation of CuInO2 nanoparticles based on the Cu2O pre-catalyst onto an interlayer of indium tin oxide under the electrochemical reaction. Density function theory calculation and ex-situ X-ray diffraction further prove the formation of CuInO2 nanoparticles during vigorous catalysis. The findings give important clues on how Cu-based electrocatalysts can be formed into more active materials and can provide inspiration for other Cu-based intermetallic oxides for high-efficiency CO2 reduction.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2019. p. 87
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1791
Keywords
Alkaline water splitting, CO2 reduction, Electrocatalyst, In-situ Raman spectroscopy.
National Category
Chemical Sciences Engineering and Technology
Research subject
Chemistry with specialization in Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-380575 (URN)978-91-513-0620-9 (ISBN)
Public defence
2019-05-21, Polhemsalen, 10134, Ångström Laboratory, Lägerhyddsv. 1, Uppsala, 13:15 (English)
Opponent
Supervisors
Available from: 2019-04-29 Created: 2019-03-29 Last updated: 2019-06-18
Liu, C., Qiu, Z., Brant, W., Younesi, R., Ma, Y., Edström, K., . . . Zhu, J.-F. (2018). A free standing Ru–TiC nanowire array/carbon textile cathode with enhanced stability for Li–O2 batteries. Journal of Materials Chemistry A, 6, 23659-23668
Open this publication in new window or tab >>A free standing Ru–TiC nanowire array/carbon textile cathode with enhanced stability for Li–O2 batteries
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2018 (English)In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, p. 23659-23668Article in journal (Refereed) Published
Abstract [en]

The instability of carbon cathode materials is one of the key problems that hinder the development of lithium–air/lithium–oxygen (Li–O2) batteries. In this contribution, a type of TiC-based cathode is developed as a suitable alternative to carbon based cathodes, and its stability with respect to its surface properties is investigated. Here, a free-standing TiC nanowire array cathode was in situ grown on a carbon textile, covering its exposed surface. The TiC nanowire array, via deposition with Ru nanoparticles, showed enhanced oxygen reduction/evolution activity and cyclability, compared to the one without Ru modification. The battery performance of the Li–O2cells with Ru–TiC was investigated by using in operando synchrotron radiation powder X-ray diffraction (SR-PXD) during a full cycle. With the aid of surface analysis, the role of the cathode substrate and surface modification is demonstrated. The presented results are a further step toward a wise design of stable cathodes for Li–O2 batteries.

National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-369118 (URN)DOI: 10.1039/c7ta10930j (DOI)000451813300047 ()
Funder
Swedish Research CouncilSwedish Energy Agency
Available from: 2018-12-10 Created: 2018-12-10 Last updated: 2019-03-19Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-7892-5260

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