Improved charge storage performance of a layered Mo1.33C MXene/MoS2/graphene nanocomposite

The construction of nanocomposite electrodes based on 2D materials is an efficient route for property enrichment and for exploitation of constituent 2D materials. Herein, a flexible Mo1.33C i-MXene/MoS2/graphene (MOMG) composite electrode is constructed, utilizing an environment-friendly method for high-quality graphene and MoS2 synthesis. The presence of graphene and MoS2 between MXene sheets limits the commonly observed restacking, increases the interlayer spacing, and facilitates the ionic and electronic conduction. The as-prepared MOMG electrode delivers a volumetric capacitance of 1600 F cm(-3) (450 F g(-1)) at the scan rate of 2 mV s(-1) and retains 96% of the initial capacitance after 15 000 charge/discharge cycles (10 A g(-1)). The current work demonstrates that the construction of nanocomposite electrodes is a promising route towards property enhancement for energy storage applications

The importance of store space for the experience : A qualitative study on layout and store allocations' impact on women's in store experiences in interior design stores

Syfte och Frågeställning Studiens huvudsyfte är att skapa förståelse för hur layout och gruppering i butiksmiljöer, påverkar inredningsintresserade kvinnors butiksupplevelse. För att besvara studiens syfte har följande frågeställning formulerats: Hur påverkar layout och gruppering inredningsintresserade kvinnors butiksupplevelse i fysiska inredningsbutiker där produkter grupperas efter produktkategorier jämfört med där produktkategorier mixas? Metod, Teoretisk referensram och Empiri Studien är kvalitativ med en komparativ forskningsdesign och jämför två fall vilka utgörs av butikerna Hemtex, i Kalmar, och Hjärterum, i Borås. Den teoretiska referensramen utgörs av teorier om butiksmiljö och butiksupplevelser. Teorier om layout och gruppering har även tagits fram som en del av butiksmiljö. Studiens empiri samlades in genom intervjuer av tre kunder till respektive butik samt genom två stycken observationer, av de två butiksmiljöerna. Analys och Slutsatser I analysen diskuteras empiri och teori, där empirin från respektive butik jämförs. Analysen resulterar i studiens slutsatser vilket visar att olika arbetssätt gällande layout och gruppering i inredningsbutiker resulterar i olika butiksupplevelser. En inredningsbutik vars produkter grupperas efter produktkategorier främjar en funktionsfokuserad butiksupplevelse med dess funktionalitet men begränsade utrymme för inspiration. För en positiv upplevelse lämpar sig arbetssättet därmed bäst vid en målinriktad aktivitet. Vidare visar studien att mixade produktkategorier främjar en inspirationsfokuserad upplevelse med mer utrymme för inspiration men med sämre navigering, för en positiv upplevelse krävs därför mer av personalen vid en målinriktad aktivitet men lämpar sig väl för en fritidsorienterad aktivitet.Purpose and Research question The main purpose of this study is to create understanding about how layout and space allocation, as aspects of store environments, affect the in-store customer experience (ISCX) of women interested in interior design. A question has been framed to fulfill the purpose of the study: How do layout and space allocation affect the ISCXof women interested in interior design where product are grouped by product categories compared with where product categories are mixed Method, Theoretical frame of reference and Empiricism The study is qualitative with a comparative research design that compares two cases that consist of the two stores Hemtex in Kalmar and Hjärterum in Borås. The theoretical frame of reference consists of theories about store environment and ISCX. These theories has been supplemented with theories about layout and space allocation, as a part of the store environment. The empiricism was gathered by interviews of three customers from each store and by two observations of the two store environments.  Analysis and Conclusions The analysis discuss the empiricism with the theories by comparing the empiricism of each store. The analysis is resulting in the study’s conclusions which show that different ways of working with layout and space allocations in interior design stores result in different ISCX. An interior design store with products grouped by product categories promotes a functional focused ISCX with its functionality but limited space for inspiration. The strategy is therefore most suitable for a targeted activity, for a positive experience. Further the study indicates that mixed product categories promotes an inspiring focused ISCX with more space for inspiration but less navigation, it is therefore most suitable for a leisure activity for a positive experience

Magnetism and plasmonic performance of mesoscopic hollow ceria spheres decorated with silver nanoparticles

International audienc

Enhanced supercapacitive performance of Mo1.33C MXene based asymmetric supercapacitors in lithium chloride electrolyte

Two-dimensional (2D) Mo1.33C MXene renders great potential for energy storage applications and is mainly studied in the sulfuric acid (H2SO4) electrolyte. However, H2SO4 limits the electrode potential to 0.9 V for symmetric devices and 1.3 V for asymmetric devices. Herein, we explore the electrochemical behavior of Mo1.33C MXene in LiCl electrolyte. In comparison to H2SO4, LiCl electrolyte is a neutral salt with high solubility at room temperature and low hazardousness. The analysis shows a volumetric capacitance of 815 Fcm(-3) at a scan rate of 2 mVs(-1) with a large operating potential window of -1.2 to +0.3V (vs. Ag/AgCl). This is further exploited to construct MXene-based asymmetric supercapacitors Mo1.33C//MnxOn, and the electrochemical performance is evaluated in 5M LiCl electrolyte. Owing to the wide voltage widow of the Mo1.33C//MnxOn devices (2V) and high packing density of the electrodes, we have achieved a volumetric energy density of 58 mWh/cm(3), a maximum power density of 31 Wcm(-3) and retained 92% of the initial capacitance after 10,000 charge/discharge cycles at 10 A g(-1). One of the main value propositions of this work, aside from the high energy density, is the outstanding columbic efficiency (100%), which ensures excellent cyclic stability and is highly desirable for practical applications.Funding Agencies|Knut and Alice Wallenberg (KAW) FoundationKnut &amp; Alice Wallenberg Foundation [KAW 2015.0043]; Swedish Foundation for Strategic Research (SSF)Swedish Foundation for Strategic Research [EM16-0004]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; VinnovaVinnova; Swedish Strategy Group for EU-Coordination [2018-02677]; KAW Foundation</p

Interface Interactions in Conjugated Polymer Composite with Metal Oxide Nanoparticles

This study presents the preparation, characterization, and properties of a new composite containing cerium oxide nanoparticles and a conjugated polymer. CeO2 nanoparticles prepared using the co-precipitation method were dispersed into the conjugated polymer, prepared using the palladium-catalyzed Suzuki&ndash;Miyaura cross-coupling reaction. The interface interactions between the two components and the resultant optoelectronic properties of the composite are demonstrated. According to transmission electron microscopy and X-ray absorption spectroscopy, the dispersion of CeO2 nanoparticles in the polymer matrix strongly depends on the CeO2 nanoparticle concentration and results in different degrees of charge transfer. The photo-induced charge transfer and recombination processes were studied using steady-state optical spectroscopy, which shows a significant fluorescence quenching and red shifting in the composite. The higher photo-activity of the composite as compared to the single components was observed and explained. Unexpected room temperature ferromagnetism was observed in both components and all composites, of which the origin was attributed to the topology and defects

Flexible Free-Standing MoO3/Ti3C2Tz MXene Composite Films with High Gravimetric and Volumetric Capacities

Enhancing both the energy storage and power capabilities of electrochemical capacitors remains a challenge. Herein, Ti3C2Tz MXene is mixed with MoO3 nanobelts in various mass ratios and the mixture is used to vacuum filter binder free, open, flexible, and free-standing films. The conductive Ti3C2Tz flakes bridge the nanobelts, facilitating electron transfer; the randomly oriented, and interconnected, MoO3 nanobelts, in turn, prevent the restacking of the Ti3C2Tz nanosheets. Benefitting from these advantages, a MoO3/Ti3C2Tz film with a 8:2 mass ratio exhibits high gravimetric/volumetric capacities with good cyclability, namely, 837 C g−1 and 1836 C cm−3 at 1 A g−1 for an ≈ 10 µm thick film; and 767 C g−1 and 1664 C cm−3 at 1 A g−1 for ≈ 50 µm thick film. To further increase the energy density, hybrid capacitors are fabricated with MoO3/Ti3C2Tz films as the negative electrodes and nitrogen-doped activated carbon as the positive electrodes. This device delivers maximum gravimetric/volumetric energy densities of 31.2 Wh kg−1 and 39.2 Wh L−1, respectively. The cycling stability of 94.2% retention ratio after 10 000 continuous charge/discharge cycles is also noteworthy. The high energy density achieved in this work can pave the way for practical applications of MXene-containing materials in energy storage devices

HiPIMS-grown AlN buffer for threading dislocation reduction in DC-magnetron sputtered GaN epifilm on sapphire substrate

Gallium nitride (GaN) epitaxial films on sapphire (Al2O3) substrates have been grown using reactive magnetron sputter epitaxy with a liquid Ga target. Threading dislocations density (TDD) of sputtered GaN films was reduced by using an inserted high-quality aluminum nitride (AlN) buffer layer grown by reactive high power impulse magnetron sputtering (R-HiPIMS) in a gas mixture of Ar and N2. After optimizing the Ar/N2 pressure ratio and deposition power, a high-quality AlN film exhibiting a narrow full-width at half-maximum (FWHM) value of the double-crystal x-ray rocking curve (DCXRC) of the AlN(0002) peak of 0.086° was obtained by R-HiPIMS. The mechanism giving rise the observed quality improvement is attributed to the enhancement of kinetic energy of the adatoms in the deposition process when operated in a transition mode. With the inserted HiPIMS-AlN as a buffer layer for direct current magnetron sputtering (DCMS) GaN growth, the FWHM values of GaN(0002) and (10 1‾ 1) XRC decrease from 0.321° to 0.087° and from 0.596° to 0.562°, compared to the direct growth of GaN on sapphire, respectively. An order of magnitude reduction from 2.7 × 109 cm−2 to 2.0 × 108 cm−2 of screw-type TDD calculated from the FWHM of the XRC data using the inserted HiPIMS-AlN buffer layer demonstrates the improvement of crystal quality of GaN. The result of TDD reduction using the HiPIMS-AlN buffer was also verified by weak beam dark-field (WBDF) cross-sectional transmission electron microscopy (TEM).Funding agencies: This research was funded by Vetenskapsrådet (grant number 2018-04198), Energimyndigheten (grant number 46658-1), Carl Tryggers Stiftelse (grant number CTS 22:2029) and Stiftelsen Olle Engkvist Byggmästare (grant number 197-0210). The Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University (Faculty Grant SFO-Mat-LiU 2009-00971) is acknowledged for financial support. We acknowledge STINT foundation, Sweden, for supporting this international collaboration (grant number: MG2019-8485).</p