B_(4)C-SiC-TiB_(2)ceramics were prepared by in situ reactive hot-pressing sintering with TiSi_(2)as an *** reaction pathways of TiSi_(2)and B_(4)C were *** sintering was found to be a multistep *** reaction started at...
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B_(4)C-SiC-TiB_(2)ceramics were prepared by in situ reactive hot-pressing sintering with TiSi_(2)as an *** reaction pathways of TiSi_(2)and B_(4)C were *** sintering was found to be a multistep *** reaction started at approximately 1000℃,and TiB_(2)was formed *** of Si and C started to react at 1300℃,and the unreacted Si melted at 1400℃to form a liquid ***_(2)predominantly affected the intermediate sintering process of B_(4)C and increased the sintering *** to the unique reaction process of TiSi_(2)and B_(4)C,a large number of aggregates composed of SiC and TiB_(2)were *** results showed that composite ceramics with the optimal flexural strength of 807 MPa,fracture toughness of 3.2 MPa·m1/2,and hardness of 32 GPa,were obtained when the TiSi_(2)content was 10 wt%.
WO_(3)-graphene electrochromic materials are widely used in electrochromic devices including smart windows and electronic displays,due to their ability to adjust optical transmittance in the visible and near-infrared ...
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WO_(3)-graphene electrochromic materials are widely used in electrochromic devices including smart windows and electronic displays,due to their ability to adjust optical transmittance in the visible and near-infrared ranges under low electrode ***,the uniformity of the film remains a challenge for the widely used physical mixing-coating *** this study,we present a two-dimensional material-assisted synthesis of a porous hydrated WO_(3) film(WH-rGO)based on reduced graphene oxide(rGO)nanosheets and WO_(3)(rGO-WO_(3))seed layer via a hydrothermal *** incorporation of rGO not only promotes the uniform growth of hydrated WO_(3) film,enhancing ion transport but also introduces oxygen vacancies,creating an efficient conduction pathway for charge *** resulting WH-rGO film exhibits impressive performance,achieving 71% optical modulation at 700 nm,with bleaching and coloring times of 4.2 and 1.0 *** coloration efficiency is calculated at 156.11 cm^(2)·C^(-1),and the optical modulation is maintained at 93% of the initial optical modulation after 1000 cycles applied in the +1.0 and -1.1 V potential *** work offers new insights into the role of oxygen vacancies in enhancing the electrochromic properties of hydrated WO_(3) films through the addition of *** also provides a promising approach for the synthesis of electrochromic materials,facilitating their application in smart window technologies.
The epitaxial heterostructure can be rationally designed based on the in situ growth of two compatible phases with lattice similarity,in which the modulated electronic states and tuned adsorption behaviors are conduci...
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The epitaxial heterostructure can be rationally designed based on the in situ growth of two compatible phases with lattice similarity,in which the modulated electronic states and tuned adsorption behaviors are conducive to the enhancement of electrocatalytic ***,theoretical simulations first disclose the charge transfer trend and reinforced inherent electron conduction around the epitaxial heterointerface between Ru clusters and Ni_(3)N substrate(cRu-Ni_(3)N),thus leading to the optimized adsorption behaviors and reduced activation energy ***,the defectrich nanosheets with the epitaxially grown cRu-Ni_(3)N heterointerface are successfully ***,by virtue of the superiority of intrinsic activity and reaction kinetics,such unique epitaxial heterostructure exhibits remarkable bifunctional catalytic activity toward electrocatalytic OER(226 mV@20 mA cm^(−2))and HER(32 mV@10 mA cm^(−2))in alkaline ***,it also shows great application prospect in alkaline freshwater and seawater splitting,as well as solar-to-hydrogen integrated *** work could provide beneficial enlightenment for the establishment of advanced electrocatalysts with epitaxial heterointerfaces.
Photocatalytic production of H_(2)O_(2) by polymeric carbon nitride has been regarded as a promising ap-proach for the conversion of solar energy into valuable ***,the efficiency of pristine car-bon nitride is limited...
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Photocatalytic production of H_(2)O_(2) by polymeric carbon nitride has been regarded as a promising ap-proach for the conversion of solar energy into valuable ***,the efficiency of pristine car-bon nitride is limited by the rapid charge recombination and the lack of suitable active ***,we introduce single-atom Cu anchored on N-doped graphene(Cu-NG)as a cocatalyst coupled with carbon nitride via covalent bonding to enhance photocatalytic H_(2)O_(2) *** Cu-NG/carbon nitride could broaden the light absorption from UV to near-infrared region,contributing to the photocatalytic ***,NG containing electron-rich N atoms could serve as anchoring sites for stabilizing single-atom ***,the single-atom Cu acts not only as an electron sink to steer the interfacial charge sep-aration but also as an active site for molecular oxygen adsorption and *** the synergistic effect of the enhanced interfacial charge separation and suitable active sites,Cu-NG/carbon nitride ex-hibits improved photocatalytic performance with an H_(2)O_(2) generation rate of 2856μmol g^(−1)h^(−1),which is 2.6 times that of pristine carbon *** work provides a protocol for high-performance photocat-alytic H_(2)O_(2) production using a single-atom cocatalyst.
Nickel-iron layered double hydroxides(NiFe LDHs)represent a promising candidate for oxygen evolution reaction(OER),however,are still confronted with insufficient activity,due to the slow kinetics of electrooxidation o...
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Nickel-iron layered double hydroxides(NiFe LDHs)represent a promising candidate for oxygen evolution reaction(OER),however,are still confronted with insufficient activity,due to the slow kinetics of electrooxidation of Ni^(2+)cations for the high-valent active ***,nanopore-rich NiFe LDH(PR-NiFe LDH)nanosheets were proposed for enhancing the OER activity together with *** the designed catalyst,the confined nanopores create abundant unsaturated Ni sites at edges,and decrease the migration distance of protons down to the scale of their mean free path,thus promoting the formation of high-valent Ni^(3+)/^(4+)active *** unique configuration further improves the OER stability by releasing the lattice stress and accelerating the neutralization of the local acidity during the phase ***,the optimized PR-NiFe LDH catalysts exhibit an ultralow overpotential of 278 mV at 10 mA∙cm^(−2)and a small Tafel slope of 75 mV∙dec^(−1),which are competitive among the advanced LDHs based ***,the RP-NiFe LDH catalyst was implemented in anion exchange membrane(AEM)water electrolyzer devices and operated steadily at a high catalytic current of 2 A over 80 *** results demonstrated that PR-NiFe LDH could be a viable candidate for the practical *** concept also provides valuable insights into the design of other catalysts for OER and beyond.
Facile preparation of additive-free inks with both high viscosity and high conductivity is critical for scalable screen printing of wireless electronics,yet very *** materials exhibit excellent conductivity and hydrop...
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Facile preparation of additive-free inks with both high viscosity and high conductivity is critical for scalable screen printing of wireless electronics,yet very *** materials exhibit excellent conductivity and hydrophilicity,showing great potential in the field of additive-free inks for screen ***,we demonstrate the synthesis of additive-free two-dimensional(2D)titanium carbide MXene inks,and realize screen-printed MXene wireless electronics for the first *** viscosity of MXene ink is solely regulated by tuning the size of MXene nanosheet without any additives,hence rendering the printed MXene film extremely high conductivity of 1.67×10^(5) S/m and fine printing resolution down to 0.05 mm on various flexible ***,radio frequency identification(RFID)tags fabricated using the additive-free MXene ink via screen printing exhibit stable antenna reading performance and superb *** article,thus offers a new route for the efficient,low-cost and pollution-free manufacture of printable electronics based on additive-free MXene inks.
The modification of the physicochemical properties of sulfonated poly(arylene ether nitrile) (SPAEN) proton exchange membranes was demonstrated by poly(ethylene-co-vinyl alcohol) (EVOH) doping (named SPAEN-x%). By con...
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High-nickel cathode LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)could enable lithium-ion batteries(LIBs)with high energy ***,excessive decomposition of the electrolyte would happen in the high operating voltage *** additio...
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High-nickel cathode LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)could enable lithium-ion batteries(LIBs)with high energy ***,excessive decomposition of the electrolyte would happen in the high operating voltage *** addition,the utilization of flammable organic solvents would increase safety risks in the high temperature ***,an electrolyte consisting of flame-retardant solvents with lower highest occupied molecular orbital(HOMO)level and LiDFOB salt is proposed to address above two *** a result,a thin and robust cathode-electrolyte interface containing rich LiF and Li-B-O compounds is formed on the cathode to effectively suppress electrolyte decomposition in the high operating *** NCM811||Li cell paired with this designed electrolyte possesses a capacity retention of 72%after 300 cycles at 55℃.This work provides insights into developing electrolyte for stable high-nickel cathode operated in the high temperature.
The thermal reduction of graphene oxide(GO)was performed by a tube furnace at different temperatures,and its structure evolution was investigated in *** results showed that the oxygen-containing functional groups on t...
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The thermal reduction of graphene oxide(GO)was performed by a tube furnace at different temperatures,and its structure evolution was investigated in *** results showed that the oxygen-containing functional groups on the carbon plane surface of GO gradually decomposed as the temperature increase,and the reduced graphene oxide(rGO)powder was obtained at 800℃.Then,rGO powder was sintered under 30 MPa at 1800℃using spark plasma sintering(SPS)and hot-pressing(HP)to evaluate its structural stability at high *** defect densities of rGO were reduced after high-temperature *** edge flatness and sp^(2) hybrid carbon plane structure were reconstructed *** results demonstrate that the lamellar structure of rGO maintains the structural integrity during high-temperature sintering without obvious deterioration,which provides experimental and theoretical supports for GO reinforced ceramics.
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