Traditional metals often exhibit a trade-offbetween strength and plasticity,limiting their wide application of metals in aerospace,transportation,energy industry and other fields[1-3].In order to overcome this dilemma...Traditional metals often exhibit a trade-offbetween strength and plasticity,limiting their wide application of metals in aerospace,transportation,energy industry and other fields[1-3].In order to overcome this dilemma,high-entropy alloys(HEAs),proposed by Yeh et al.and Cantor et al.,are currently of great interest in the materials community due to their excellent mechanical properties[4-7].To further promote the wide application of HEAs in industrial production,Lu et al.developed a new eutectic high-entropy alloy(EHEAs)by combining the potential advantages of traditional eutectic alloys and HEAs[8-11].展开更多
Internal rotation of conjugated organic backbone seriously impaired room temperature phosphorescence(RTP),leading to rare realization of ultra-long afterglows with RTP lifetimes over 2 s in non-bibulous polymers.Herei...Internal rotation of conjugated organic backbone seriously impaired room temperature phosphorescence(RTP),leading to rare realization of ultra-long afterglows with RTP lifetimes over 2 s in non-bibulous polymers.Herein,N-(bromophenyl)carbazoles are cyclized to lock up phenyl-carbazol internal rotation in advance and the fused nitrogen hetero-cyclic compounds are doped into poly(methyl methacrylate)(PMMA).The results show that locking up the molecular internal rotation can achieve ultra-long RTP polymers with lifetimes over 2 s,in contrast,the unlocked molecules hardly emit RTP in PMMA.The high-lying triplet excitons can transfer the energy to low-lying organic fluorescent dyes,and the persistent multicolor afterglows including white emission can be readily modulated.This work discloses an effective and extendable dopant molecular strategy for developing high-performance ultra-long organic RTP polymers.展开更多
This study reports the development of a novel amino‐functionalized ionic liquid catalyst,namely 1‐butyl‐3‐methylimidazolium amino triazole([EMIM]ATZ),for the efficient and sustainable synthesis of ethyl methyl car...This study reports the development of a novel amino‐functionalized ionic liquid catalyst,namely 1‐butyl‐3‐methylimidazolium amino triazole([EMIM]ATZ),for the efficient and sustainable synthesis of ethyl methyl carbonate(EMC)via transesterification of dimethyl carbonate(DMC)and ethanol(C_(2)H_(5)OH)at room temperature.Addressing the limitations of conventional catalytic systems that require elevated temperatures(>75℃),[EMIM]ATZ achieves 62%DMC conversion and 56%EMC yield within 8 h under room temperature(25℃),while conventional ionic liquids([EMIM]Cl,[EMIM]BF_(4),[EMIM]PF_(6) etc.)showed almost no activity at room temperature.The catalyst's superior activity stems from its strong basicity(pH≈9.2)and enhanced CO_(2) absorption capacity(200 mg·g^(−)1),which synergistically activate C2H5OH and stabilize reaction intermediates.Structural characterization via FTIR and thermogravimetric analysis(TGA)confirmed the catalyst's thermal stability and recyclability,with no significant degradation observed over five reuse cycles(89%activity retention).In addition,the ionic liquid was also able to catalyze the synthesis of methyl propyl carbonate(PMC)and methyl butyl carbonate(BMC)at room temperature.展开更多
Stimulus-responsive organic room temperature phosphorescent(RTP)materials have received significant attention in bioimaging,sensing,and data storage because of their controllable dynamic variability and rapid response...Stimulus-responsive organic room temperature phosphorescent(RTP)materials have received significant attention in bioimaging,sensing,and data storage because of their controllable dynamic variability and rapid response.Organic cocrystals,with tailor-designed optical properties through manipulation of their aggregate structures,have proven to be very effective in elucidating the structureproperty relationship of organic RTP materials at the molecular level.Therefore,enhancing RTP through rigid frameworks that promote intersystem crossing is a valid approach.Notably,the realization of organic RTP co-crystal performance by altering the components or adjusting the crystal lattices is highly appealing;however,this has not been fully addressed.In this study,an organic RTP cocrystal,4,40-bipyridine(44BD),was employed as the host,and 1,4-diiodotetrafluorobenzene(DITF)and 4-bromo-2,3,5,6-tetrafluorobenzoic acid(TFBA)were employed as vips.The 44BD-DITF co-crystal exhibited an orange RTP,whereas 44BD-TFBA displayed a bright yellow RTP.Crystal analysis and theoretical calculations revealed that dense molecular packing and abundant intermolecular interactions within these co-crystals are crucial for the emergence of RTP.Notably,both co-crystals show a reversible acid/base stimulus response,that is,exposure to hydrochloric acid(HCl)fumes results in quenching of their RTP,which can be subsequently restored by triethylamine(TEA)fumigation.This study presents an effective approach towards reversible RTP switching in organic co-crystals,thus offering opportunities for the development of acid/base stimulus-responsive materials for next-generation applications.展开更多
Solid-state batteries(SSBs)with thermal stable solid-state electrolytes(SSEs)show intrinsic capacity and great potential in energy density improvement.SSEs play critical role,however,their low ionic conductivity at ro...Solid-state batteries(SSBs)with thermal stable solid-state electrolytes(SSEs)show intrinsic capacity and great potential in energy density improvement.SSEs play critical role,however,their low ionic conductivity at room temperature and high brittleness hinder their further development.In this paper,polypropylene(PP)-polyvinylidene fluoride(PVDF)-Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)-Lithium bis(trifluoromethane sulphonyl)imide(LiTFSI)multi-layered composite solid electrolyte(CSE)is prepared by a simple separator coating strategy.The incorporation of LATP nanoparticle fillers and high concentration LiTFSI not only reduces the crystallinity of PVDF,but also forms a solvation structure,which contributes to high ionic conductivity in a wide temperature.In addition,using a PP separator as the supporting film,the mechanical strength of the electrolyte was improved and the growth of lithium dendrites are effectively inhibited.The results show that the CSE prepared in this paper has a high ionic conductivity of 6.38×10^(-4)S/cm at room temperature and significantly improves the mechanical properties,the tensile strength reaches 11.02 MPa.The cycle time of Li/Li symmetric cell assembled by CSE at room temperature can exceed 800 h.The Li/LFP full cell can cycle over 800 cycles and the specific capacity of Li/LFP full cell can still reach 120 m Ah/g after 800 cycles at 2 C.This CSE has good cycle stability and excellent mechanical strength at room temperature,which provides an effective method to improve the performance of solid electrolytes under moderate condition.展开更多
Traditional resistive semiconductor gas sensors suffer from high operating temperatures and poor selectivity.Thus,to address these issues,a highly selective nitrogen dioxide(NO_(2))sensor based on lead sulfide(PbS)qua...Traditional resistive semiconductor gas sensors suffer from high operating temperatures and poor selectivity.Thus,to address these issues,a highly selective nitrogen dioxide(NO_(2))sensor based on lead sulfide(PbS)quantum dots(QDs)–lead molybdate(PbMoO_(4))–molybdenum disulfide(MoS_(2))ternary nanocomposites operating at room temperature was fabricated herein.The ternary nanocomposites were synthesized using an in situ method,yielding Pb S QDs with an average size of~10 nm and PbMoO_(4)nanoparticles in the 10-to 20-nm range,uniformly distributed on ultrathin MoS_(2)nanosheets with an average thickness of~7 nm.The optimized sensor demonstrated a significant improvement in response to 1 ppm NO_(2)at 25℃,achieving a response of 44.5%,which was approximately five times higher than that of the pure MoS_(2)-based sensor(8.5%).The sensor also achieved relatively short response/recovery times and full recovery properties.Notably,the optimal sensor displayed extraordinary selectivity toward NO_(2),showing negligible responses to different interfering gases.Density functional theory(DFT)calculations were conducted to elucidate the underlying sensing mechanism,which was attributed to the enhanced specific surface area,the receptor function of both PbS QDs and PbMoO_(4)nanoparticles,and the transducer function of MoS_(2) nanosheets.展开更多
Realizing ferromagnetic semiconductors with high Curie temperature TC is still a challenge in spintronics.Recent experiments have reported two-dimensional(2D)room temperature ferromagnetic metals,such as monolayer Cr_...Realizing ferromagnetic semiconductors with high Curie temperature TC is still a challenge in spintronics.Recent experiments have reported two-dimensional(2D)room temperature ferromagnetic metals,such as monolayer Cr_(3)Te_(6).In this paper,through density functional theory(DFT)calculations,we propose a method to obtain 2D high TC ferromagnetic semiconductors through element replacement in these ferromagnetic metals.We predict that monolayer(Cr_(4/6),Mo_(2/6))_(3)Te_(6),created via element replacement in monolayer Cr_(3)Te_(6),is a room-temperature ferromagnetic semiconductor exhibiting a band gap of 0.34 eV and a TC of 384 K.Our analysis reveals that the metal-to-semiconductor transition stems from the synergistic interplay of Mo-induced lattice distortion,which resolves band overlap,and the electronic contributions of Mo dopants,which further drive the formation of a distinct band gap.The origin of the high TC is traced to strong superexchange coupling between magnetic ions,analyzed via the superexchange model with DFT and Wannier function calculations.Considering the fast developments in fabrication and manipulation of 2D materials,our theoretical results propose an approach to explore high-temperature ferromagnetic semiconductors derived from experimentally obtained 2D high-temperature ferromagnetic metals through element replacement.展开更多
Lithium-carbon dioxide(Li-CO_(2))batteries using high ion-conductive inorganic molten salt electrolytes have recently attracted much attention due to the high energy density and potential application of carbon neutral...Lithium-carbon dioxide(Li-CO_(2))batteries using high ion-conductive inorganic molten salt electrolytes have recently attracted much attention due to the high energy density and potential application of carbon neutrality.However,the poor Li-ion conductivity of the molten-salt electrolytes at room temperature(RT)makes these batteries lose most of their capacity and power as the temperature falls below 80℃.Here,inspired by the greenhouse effect,we report an RT molten salt Li-CO_(2)battery where solar energy can be efficiently harvested and converted into heat that is further localized on the cathode consisting of plasmonic ruthenium(Ru)catalysts and Li_(2)CO_(3)-based products via a greenhouse-like phenomenon.As a result,the solar-driven molten salt Li-CO_(2)battery demonstrates a larger full discharge/charge capacity of 9.5 mA h/8.1 mA h,and a longer cycle lifespan of 250 cycles at 500 mA/g with a limited capacity of 500 mA h/g at RT than the molten salt Li-CO_(2)battery at 130℃.Notably,the average temperature of the cathode increases by 8℃ after discharge to 0.75 mA h,which indicates the infrared radiation from Ru catalysts can be effectively suppressed by discharged Li_(2)CO_(3)-based products.This battery technology paves the way for developing low-temperature molten salt energy storage devices.展开更多
Supersolidity is a counterintuitive quantum phase of matter where the long-range spatial order of a solid coexists with the frictionless flow characteristic of a superfluid.Recently,evidence of supersolidity has been ...Supersolidity is a counterintuitive quantum phase of matter where the long-range spatial order of a solid coexists with the frictionless flow characteristic of a superfluid.Recently,evidence of supersolidity has been demonstrated in polariton condensates in III-V photonic crystal microcavities by condensing into a topological bound state in the continuum,offering a new light-matter hybrid platform for exploring such quantum phase.In this work,we propose a theoretical scheme for realizing room-temperature supersolidity based on halide perovskite exciton polaritons operating in the optical parametric oscillation regime.By employing a waveguide microcavity geometry,we confine polariton scattering direction in reciprocal space,enabling controlled momentum selection.Leveraging the intrinsic nonlinear interactions among polaritons,we theoretically demonstrate the spontaneous breaking of both continuous translational symmetry and global phase symmetry,i.e.,the evidence of supersolidity.Furthermore,we identify a tunable phase transition sequence in our system:from a Bose-Einstein condensate to a supersolid phase,and ultimately to an insulating phase,as the nonlinear interaction strength increases.展开更多
Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrog...Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrogen-vacancy(NV)centers in diamond,have demonstrated remarkable capabilities in this domain[1–4].However,these systems are limited by their rigid lattice structures and lack tunability.展开更多
Bi_(2)Fe_(4)O_(9) nanosheets were prepared using a hydrothermal method,followed by the introduction of NaBH_(4) and hightemperature calcination,which successfully induced strong ferromagnetism in the material at room ...Bi_(2)Fe_(4)O_(9) nanosheets were prepared using a hydrothermal method,followed by the introduction of NaBH_(4) and hightemperature calcination,which successfully induced strong ferromagnetism in the material at room temperature(M_(S)=10.22 emu/g and M_(r)=2.93 emu/g).This work demonstrates for the first time that Bi_(2)Fe_(4)O_(9) can exhibit such strong ferromagnetism at room temperature,with potential for further enhancements.Meanwhile,the ferroelectric properties of the samples were investigated.X-ray diffraction confirmed that the samples were single-phase with no detectable impurities.Based on a series of characterization analyses,it is inferred that Bi vacancies contribute to the observed strong magnetism.展开更多
Photonic crystal surface emitting lasers(PCSELs)utilize the Bragg diffraction of two-dimensional photonic crystals to achieve a single-mode output with a high power and a small divergence angle,and has recently attrac...Photonic crystal surface emitting lasers(PCSELs)utilize the Bragg diffraction of two-dimensional photonic crystals to achieve a single-mode output with a high power and a small divergence angle,and has recently attracted much attention^([1−3]).In 2023,Kyoto University reported GaAs-based 945 nm PCSELs with a continuous-wave(CW)single-mode output power of exceeding 50 W,and a narrow beam divergence angle of 0.05°,demonstrating a brightness of 1 GW·cm^(−2)·sr^(−1),which rivals those of the existing bulky lasers^([4]).展开更多
Flower-like tin oxide-supported platinum（Pt/SnOx） with a hierarchical structure was synthesized by a hydrothermal method and characterized by XRD,SEM,TEM,high resolution TEM,XPS and nitrogen adsorption.The flower-li...Flower-like tin oxide-supported platinum（Pt/SnOx） with a hierarchical structure was synthesized by a hydrothermal method and characterized by XRD,SEM,TEM,high resolution TEM,XPS and nitrogen adsorption.The flower-like Pt/SnOx microspheres of 1 μm in diameter were composed of staggered petal-like nanosheets with a thickness of 20 nm.Pt nanoparticles（NPs） of 2-3 nm were well dispersed on the SnOx nanosheets.The catalyst was tested in the catalytic oxidation of gaseous formaldehyde（HCHO） at room temperature,and exhibited enhanced activity compared to Pt NPs supported on commercial SnO and ground SnOx.HCHO removal of 87%was achieved over the hierarchical Pt/SnOx after 1 h of reaction,which was 1.5 times that over the ground SnOx-supported Pt（Pt/g-SnOx）,and the high activity was maintained after six recycles,showing the high stability of this catalyst.HCHO decomposition kinetics was modeled as a second order reaction.The reaction rate constant for Pt/SnOx was 5.6 times higher than Pt/g-SnOx.The hierarchical pore structure was beneficial for the diffusion and adsorption of HCHO molecules,and the highly dispersed Pt NPs on the SnOx nanosheets were the active sites for the oxidative decomposition of HCHO into CO2 and H2O.This study provided a promising approach for designing efficient catalysts for indoor HCHO removal at ambient temperature.展开更多
Room temperature phosphorescence(RTP) has drawn increasing attention for its great potential in practical applications.Polymers with large molecular weights and long chains tend to form coil, which can endow them with...Room temperature phosphorescence(RTP) has drawn increasing attention for its great potential in practical applications.Polymers with large molecular weights and long chains tend to form coil, which can endow them with a high degree of possible rigidity and result in the much restricted non-radiative transition. Also, the intertwined structure of polymers could isolate the oxygen and humidity effectively, thus reducing the consumption of triplet excitons. In consideration of these points, organic polymers would be another kind of ideal platform to realize RTP effect. This short review summarized the design strategy of the purely organic room temperature phosphorescence polymers, mainly focusing on the building forms of polymers and the corresponding inherent mechanisms,and also gives some outlooks on the further exploration of this field at the end of this paper.展开更多
The SiO_2 nanoparticles were coated on the surface of graphene oxide(GO) by sol-gel method to get the SiO_2-G compound.The SiO_2-G was restored and oleophylically modified to prepare hydrophobic modified SiO_2-G(HM-Si...The SiO_2 nanoparticles were coated on the surface of graphene oxide(GO) by sol-gel method to get the SiO_2-G compound.The SiO_2-G was restored and oleophylically modified to prepare hydrophobic modified SiO_2-G(HM-SiO_2-G) which was subsequently added to silicone rubber matrix to prepare two-component room temperature vulcanized(RTV-2) thermal conductive silicone rubber. The morphology, chemical structure and dispersity of the modified graphene were characterized with SEM, FTIR, Raman, and XPS methods.In addition, the heat-resistance behavior, mechanical properties, thermal conductivity, and electrical conductivity of the RTV-2 silicone rubber were also studied systematically. The results showed that the SiO_2 nanoparticles were coated on graphene oxide successfully, and HM-SiO_2-G was uniformly dispersed in RTV-2 silicone rubber. The addition of HM-SiO_2-G could effectively improve the thermal stability, mechanical properties and thermal conductivity of RTV-2 silicone rubber and had no great influence on the electrical insulation performance.展开更多
A serial of ordered meso-macroporous phosphotungstic acid(HPW) supported on SiO2 nanocomposites were successfully prepared by a homogeneous precipitation method, using monodispersed polystyrene(PS) microspheres and ca...A serial of ordered meso-macroporous phosphotungstic acid(HPW) supported on SiO2 nanocomposites were successfully prepared by a homogeneous precipitation method, using monodispersed polystyrene(PS) microspheres and cationic surfactant as structure directing agent. These nanocomposites were used as catalysts for oxidative desulfurization(ODS) of model fuel. The materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), N2 adsorption-desorption isothrem, X-ray diffraction(XRD), and Fourier transform infrared spectra(FTIR). The characterization results suggested that the as-prepared material possessed ordered meso-macroporous architectures with Keggin type phosphotungstic acid dispersed homogeneously in SiO2 matrix. Under the selected reaction conditions, dibenzothiophene(DBT) in model fuel can be removed within 2 h at room temperature(30 ℃). In addition, only 1.2% of efficiency lose than the fresh catalyst even after 5 cycles.展开更多
A reciprocating magnetic refrigerator was developed based on the active magnetic regeneration technology. Rare earth metal Gd and intermetallic compound LaFe11.2Co0.7Si1.1 were used as the magnetic operating materials...A reciprocating magnetic refrigerator was developed based on the active magnetic regeneration technology. Rare earth metal Gd and intermetallic compound LaFe11.2Co0.7Si1.1 were used as the magnetic operating materials in the machine. The particles of the magnetic operating materials, with diameter of 0.5-2 mm and total mass of 950 g, were mounted in the cooling bed. A magnetic field was assembled using NdFeB rare earth permanent magnets. It had the magnetic field space of Φ 34×200 and the magnetic induction of 1.5 T. The water at pH=10 is used as a heat transfer fluid. When the ambient temperature is 296 K, a temperature span of 18 K was achieved after operation of 45 min at a frequency of 0.178 Hz. The temperature span and the output power increase significantly with the increasing velocity of heat transfer.展开更多
Nano-sized cerium-titanium pyrophosphates Ce1-xTixP2O7 （with x = 0, 0.2, 0.5, 0.7, 0.9, and 1.0） were obtained by grinding a mixture of Ce（SO4）2·4H2O, Ti（SO4）2, and Na4P2O7·10H2O in the presence of sur...Nano-sized cerium-titanium pyrophosphates Ce1-xTixP2O7 （with x = 0, 0.2, 0.5, 0.7, 0.9, and 1.0） were obtained by grinding a mixture of Ce（SO4）2·4H2O, Ti（SO4）2, and Na4P2O7·10H2O in the presence of surfactant PEG-400 at room temperature, washing the mixture with water to remove soluble inorganic salts, and drying at 100℃. The products and their calcined samples were characterized using ultraviolet-visible spectroscopy （UV-vis）, thermogravimetry and differential thermal analyses （TG/DTA）, X-ray powder diffraction （XRD）, and transmission electron microscopy （TEM）. The results show that nano-sized Ce1-xTixP2O7 behave as an excellent UV-shielding material. Thereinto, the CeP2O7 has the most excellent UV-shielding effect, and the amorphous state of Ce0.8Ti0.2P2O7 can keep at a higher temperature than CeP2O7. Therefore, the stabilization of the amorphous state of the cerium pyrophosphates was carded out by doping titanium. This stabilization is a significant improvement, which enables to apply these amorphous pyrophosphates not only to cosmetics and paints, but also plastics and films.展开更多
The NO oxidation processes on CrO_2(110) was investigated by virtue of DFT + U calculation together with microkinetic analysis, aiming to uncover the reaction mechanism and activity-limiting factors for CrO_2 catalyst...The NO oxidation processes on CrO_2(110) was investigated by virtue of DFT + U calculation together with microkinetic analysis, aiming to uncover the reaction mechanism and activity-limiting factors for CrO_2 catalyst. It was found that NO oxidation on CrO_2(110) has to be triggered with the lattice Obri involved(Mars-van Krevelen mechanism) rather than the Langmuir-Hinshelwood path occurring at the Cr_(5 c) sites alone. Specifically, the optimal reaction path was identified. Quantitatively, the microkinetic analysis showed that CrO_2(110) can exhibit a high turnover rate of 0.978 s^(-1) for NO oxidation at room temperature.Such an activity could originate from the bifunctional synergetic catalytic mechanism, in which the Cr_(5c)sites can exclusively adsorb NO and the Obri is very reactive and provides oxidative species. However, it is worth noting that, as the reactive Obri tightly binds NO_2, the nitrate species was found to be difficult removed and constituted the key poisoning species, eventually limiting the overall activity of CrO_2. This work demonstrated the considerable catalytic ability of CrO_2 for NO oxidation at room temperature, and the understanding may facilitate the further design of more active Cr-based catalyst.展开更多
Uniform CeVO4 nanowires with diameter of about 25 nm were synthesized by the water-in-oil microemulsion method at room temperature from cerous chloride, sodium orthophosphate, sodium chloride, cyclohexane, Triton X-10...Uniform CeVO4 nanowires with diameter of about 25 nm were synthesized by the water-in-oil microemulsion method at room temperature from cerous chloride, sodium orthophosphate, sodium chloride, cyclohexane, Triton X-100 and cetyltrimethyl ammonium bromide （CTAB）. The crystal structure and morphology of the nanowires were characterized by XRD and TEM, respectively. The UV-vis absorption was detected by UV-vis spectrophotometer techniques. The results showed that as-prepared nanowires with the hexagonal phase have obvious quantum confinement effect and semiconductor characteristics. Little sodium chloride could play a positive role on the formation of CePO4 nanowires at room temperature. The size of the nanowires can be controlled through the joining of sodium chloride. C 2009 Yi Bin Yin. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
基金financial supported by the Natural Science Foundation of Jiangsu Provincial Education Department(No.24KJB430003)the Natural Science Foundation for Young Scholars of Jiangsu Province(No.BK20240979)+3 种基金support of Natural Science Foundation for Young Scholars of Jiangsu Province(No.BK20220628)the National Natural Science Foundation for Young Scholars of China(52301130)the Changzhou Sci&Tech program(No.GJ20220153)support of the Natural Science Foundation of Jiangsu Provincial Education Department(No.21KJB430001).
文摘Traditional metals often exhibit a trade-offbetween strength and plasticity,limiting their wide application of metals in aerospace,transportation,energy industry and other fields[1-3].In order to overcome this dilemma,high-entropy alloys(HEAs),proposed by Yeh et al.and Cantor et al.,are currently of great interest in the materials community due to their excellent mechanical properties[4-7].To further promote the wide application of HEAs in industrial production,Lu et al.developed a new eutectic high-entropy alloy(EHEAs)by combining the potential advantages of traditional eutectic alloys and HEAs[8-11].
文摘Internal rotation of conjugated organic backbone seriously impaired room temperature phosphorescence(RTP),leading to rare realization of ultra-long afterglows with RTP lifetimes over 2 s in non-bibulous polymers.Herein,N-(bromophenyl)carbazoles are cyclized to lock up phenyl-carbazol internal rotation in advance and the fused nitrogen hetero-cyclic compounds are doped into poly(methyl methacrylate)(PMMA).The results show that locking up the molecular internal rotation can achieve ultra-long RTP polymers with lifetimes over 2 s,in contrast,the unlocked molecules hardly emit RTP in PMMA.The high-lying triplet excitons can transfer the energy to low-lying organic fluorescent dyes,and the persistent multicolor afterglows including white emission can be readily modulated.This work discloses an effective and extendable dopant molecular strategy for developing high-performance ultra-long organic RTP polymers.
基金supported by Shandong Energy Institute(SEI U202321)Gansu Province Young Talents(Team Project)(2025QNTD41)+2 种基金Natural Science Foundation of Shandong(ZR2024QB172)The Major Project of Gansu Province(21ZD4WA021,23JRRA603)Natural Science Foundation of Gansu(24JRRA060).
文摘This study reports the development of a novel amino‐functionalized ionic liquid catalyst,namely 1‐butyl‐3‐methylimidazolium amino triazole([EMIM]ATZ),for the efficient and sustainable synthesis of ethyl methyl carbonate(EMC)via transesterification of dimethyl carbonate(DMC)and ethanol(C_(2)H_(5)OH)at room temperature.Addressing the limitations of conventional catalytic systems that require elevated temperatures(>75℃),[EMIM]ATZ achieves 62%DMC conversion and 56%EMC yield within 8 h under room temperature(25℃),while conventional ionic liquids([EMIM]Cl,[EMIM]BF_(4),[EMIM]PF_(6) etc.)showed almost no activity at room temperature.The catalyst's superior activity stems from its strong basicity(pH≈9.2)and enhanced CO_(2) absorption capacity(200 mg·g^(−)1),which synergistically activate C2H5OH and stabilize reaction intermediates.Structural characterization via FTIR and thermogravimetric analysis(TGA)confirmed the catalyst's thermal stability and recyclability,with no significant degradation observed over five reuse cycles(89%activity retention).In addition,the ionic liquid was also able to catalyze the synthesis of methyl propyl carbonate(PMC)and methyl butyl carbonate(BMC)at room temperature.
基金supported by the Natural Science Foundation of Jilin Province(20240101003JC)the Department of Science and Technology of Jilin Province(20230508176RC and 20240602063RC)+1 种基金the China Postdoctoral Science Foundation(2024M751080 and 2024T170337)the National Natural Science Foundation of China(52073116,22275065,22302073).
文摘Stimulus-responsive organic room temperature phosphorescent(RTP)materials have received significant attention in bioimaging,sensing,and data storage because of their controllable dynamic variability and rapid response.Organic cocrystals,with tailor-designed optical properties through manipulation of their aggregate structures,have proven to be very effective in elucidating the structureproperty relationship of organic RTP materials at the molecular level.Therefore,enhancing RTP through rigid frameworks that promote intersystem crossing is a valid approach.Notably,the realization of organic RTP co-crystal performance by altering the components or adjusting the crystal lattices is highly appealing;however,this has not been fully addressed.In this study,an organic RTP cocrystal,4,40-bipyridine(44BD),was employed as the host,and 1,4-diiodotetrafluorobenzene(DITF)and 4-bromo-2,3,5,6-tetrafluorobenzoic acid(TFBA)were employed as vips.The 44BD-DITF co-crystal exhibited an orange RTP,whereas 44BD-TFBA displayed a bright yellow RTP.Crystal analysis and theoretical calculations revealed that dense molecular packing and abundant intermolecular interactions within these co-crystals are crucial for the emergence of RTP.Notably,both co-crystals show a reversible acid/base stimulus response,that is,exposure to hydrochloric acid(HCl)fumes results in quenching of their RTP,which can be subsequently restored by triethylamine(TEA)fumigation.This study presents an effective approach towards reversible RTP switching in organic co-crystals,thus offering opportunities for the development of acid/base stimulus-responsive materials for next-generation applications.
基金supported by National Natural Science Foundation of China(No.22209075)。
文摘Solid-state batteries(SSBs)with thermal stable solid-state electrolytes(SSEs)show intrinsic capacity and great potential in energy density improvement.SSEs play critical role,however,their low ionic conductivity at room temperature and high brittleness hinder their further development.In this paper,polypropylene(PP)-polyvinylidene fluoride(PVDF)-Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)-Lithium bis(trifluoromethane sulphonyl)imide(LiTFSI)multi-layered composite solid electrolyte(CSE)is prepared by a simple separator coating strategy.The incorporation of LATP nanoparticle fillers and high concentration LiTFSI not only reduces the crystallinity of PVDF,but also forms a solvation structure,which contributes to high ionic conductivity in a wide temperature.In addition,using a PP separator as the supporting film,the mechanical strength of the electrolyte was improved and the growth of lithium dendrites are effectively inhibited.The results show that the CSE prepared in this paper has a high ionic conductivity of 6.38×10^(-4)S/cm at room temperature and significantly improves the mechanical properties,the tensile strength reaches 11.02 MPa.The cycle time of Li/Li symmetric cell assembled by CSE at room temperature can exceed 800 h.The Li/LFP full cell can cycle over 800 cycles and the specific capacity of Li/LFP full cell can still reach 120 m Ah/g after 800 cycles at 2 C.This CSE has good cycle stability and excellent mechanical strength at room temperature,which provides an effective method to improve the performance of solid electrolytes under moderate condition.
基金supported by the National Natural Science Foundation of China(No.52274255)Fundamental Research Funds for the Central Universities,China(Nos.N2401003,N2301003,N2201008,N2201004,and N2301025)+3 种基金Liaoning Revitalization Talents Program,China(No.XLYC2202028)Postdoctoral Foundation of Northeastern University,ChinaYoung Elite Scientists Sponsorship Program by CAST(No.2022QNRC001)China Postdoctoral Science Foundation(No.2022M720025)。
文摘Traditional resistive semiconductor gas sensors suffer from high operating temperatures and poor selectivity.Thus,to address these issues,a highly selective nitrogen dioxide(NO_(2))sensor based on lead sulfide(PbS)quantum dots(QDs)–lead molybdate(PbMoO_(4))–molybdenum disulfide(MoS_(2))ternary nanocomposites operating at room temperature was fabricated herein.The ternary nanocomposites were synthesized using an in situ method,yielding Pb S QDs with an average size of~10 nm and PbMoO_(4)nanoparticles in the 10-to 20-nm range,uniformly distributed on ultrathin MoS_(2)nanosheets with an average thickness of~7 nm.The optimized sensor demonstrated a significant improvement in response to 1 ppm NO_(2)at 25℃,achieving a response of 44.5%,which was approximately five times higher than that of the pure MoS_(2)-based sensor(8.5%).The sensor also achieved relatively short response/recovery times and full recovery properties.Notably,the optimal sensor displayed extraordinary selectivity toward NO_(2),showing negligible responses to different interfering gases.Density functional theory(DFT)calculations were conducted to elucidate the underlying sensing mechanism,which was attributed to the enhanced specific surface area,the receptor function of both PbS QDs and PbMoO_(4)nanoparticles,and the transducer function of MoS_(2) nanosheets.
基金supported by the National Key R&D Program of China(Grant No.2022YFA1405100)Chinese Academy of Sciences Project for Young Scientists in Basic Research(Grant No.YSBR-030)+3 种基金the Basic Research Program of the Chinese Academy of Sciences Based on Major Scientific Infrastructures(Grant No.JZHKYPT-2021-08)GS was supported in part by the Innovation Program for Quantum Science and Technology(Grant No.2024ZD03005)the National Natural Science Foundation of China(Grant No.12447101)Chinese Academy of Sciences.
文摘Realizing ferromagnetic semiconductors with high Curie temperature TC is still a challenge in spintronics.Recent experiments have reported two-dimensional(2D)room temperature ferromagnetic metals,such as monolayer Cr_(3)Te_(6).In this paper,through density functional theory(DFT)calculations,we propose a method to obtain 2D high TC ferromagnetic semiconductors through element replacement in these ferromagnetic metals.We predict that monolayer(Cr_(4/6),Mo_(2/6))_(3)Te_(6),created via element replacement in monolayer Cr_(3)Te_(6),is a room-temperature ferromagnetic semiconductor exhibiting a band gap of 0.34 eV and a TC of 384 K.Our analysis reveals that the metal-to-semiconductor transition stems from the synergistic interplay of Mo-induced lattice distortion,which resolves band overlap,and the electronic contributions of Mo dopants,which further drive the formation of a distinct band gap.The origin of the high TC is traced to strong superexchange coupling between magnetic ions,analyzed via the superexchange model with DFT and Wannier function calculations.Considering the fast developments in fabrication and manipulation of 2D materials,our theoretical results propose an approach to explore high-temperature ferromagnetic semiconductors derived from experimentally obtained 2D high-temperature ferromagnetic metals through element replacement.
基金supported by the National Natural Science Foundation of China(NSFC,62104099,61921005,62105048,62204117 and 62073299)the Science and Technology Research Program of Chongqing Education Commission(KJQN202100633)+5 种基金the Postdoctoral Science Foundation of China(2021M693768 and 2021M701057)the Key Scientific Research Project in Colleges and Universities of Henan Province,China(21A416001)the Key Laboratory for Special Functional Materials(KEKT2022-06)the Natural Science Foundation of Jiangsu Province(BK20210275 and BK20230498)the support from Jiangsu Province Science Foundation for Youths(BK20210275)National Natural Science Foundation of China(NSFC,62204117)。
文摘Lithium-carbon dioxide(Li-CO_(2))batteries using high ion-conductive inorganic molten salt electrolytes have recently attracted much attention due to the high energy density and potential application of carbon neutrality.However,the poor Li-ion conductivity of the molten-salt electrolytes at room temperature(RT)makes these batteries lose most of their capacity and power as the temperature falls below 80℃.Here,inspired by the greenhouse effect,we report an RT molten salt Li-CO_(2)battery where solar energy can be efficiently harvested and converted into heat that is further localized on the cathode consisting of plasmonic ruthenium(Ru)catalysts and Li_(2)CO_(3)-based products via a greenhouse-like phenomenon.As a result,the solar-driven molten salt Li-CO_(2)battery demonstrates a larger full discharge/charge capacity of 9.5 mA h/8.1 mA h,and a longer cycle lifespan of 250 cycles at 500 mA/g with a limited capacity of 500 mA h/g at RT than the molten salt Li-CO_(2)battery at 130℃.Notably,the average temperature of the cathode increases by 8℃ after discharge to 0.75 mA h,which indicates the infrared radiation from Ru catalysts can be effectively suppressed by discharged Li_(2)CO_(3)-based products.This battery technology paves the way for developing low-temperature molten salt energy storage devices.
基金supported by the National Natural Science Foundation of China(Grant No.12434011 obtained by Q X)the China Postdoctoral Science Foundation(Grant No.Y24PJ2425214 obtained by L T).
文摘Supersolidity is a counterintuitive quantum phase of matter where the long-range spatial order of a solid coexists with the frictionless flow characteristic of a superfluid.Recently,evidence of supersolidity has been demonstrated in polariton condensates in III-V photonic crystal microcavities by condensing into a topological bound state in the continuum,offering a new light-matter hybrid platform for exploring such quantum phase.In this work,we propose a theoretical scheme for realizing room-temperature supersolidity based on halide perovskite exciton polaritons operating in the optical parametric oscillation regime.By employing a waveguide microcavity geometry,we confine polariton scattering direction in reciprocal space,enabling controlled momentum selection.Leveraging the intrinsic nonlinear interactions among polaritons,we theoretically demonstrate the spontaneous breaking of both continuous translational symmetry and global phase symmetry,i.e.,the evidence of supersolidity.Furthermore,we identify a tunable phase transition sequence in our system:from a Bose-Einstein condensate to a supersolid phase,and ultimately to an insulating phase,as the nonlinear interaction strength increases.
文摘Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrogen-vacancy(NV)centers in diamond,have demonstrated remarkable capabilities in this domain[1–4].However,these systems are limited by their rigid lattice structures and lack tunability.
基金supported by the Natural Science Foundation of Gansu Province of China(Grant No.24JRRA171)the Postgraduate“Innovative Star”Project of Gansu Provincial Department of Education(Grant No.2025CXZX-587)the National Natural Science Foundation of China(Grant No.52162040)。
文摘Bi_(2)Fe_(4)O_(9) nanosheets were prepared using a hydrothermal method,followed by the introduction of NaBH_(4) and hightemperature calcination,which successfully induced strong ferromagnetism in the material at room temperature(M_(S)=10.22 emu/g and M_(r)=2.93 emu/g).This work demonstrates for the first time that Bi_(2)Fe_(4)O_(9) can exhibit such strong ferromagnetism at room temperature,with potential for further enhancements.Meanwhile,the ferroelectric properties of the samples were investigated.X-ray diffraction confirmed that the samples were single-phase with no detectable impurities.Based on a series of characterization analyses,it is inferred that Bi vacancies contribute to the observed strong magnetism.
基金funded by National Key R&D Program of China(Grant Nos.2024YFB3612200,2023YFB3609601,2022YFB3604300,2022YFB2802801,2022YFB3604802)Natural Science Foundation of China(Grant Nos.U24A20300,62174174,62274177,62275263,62325406,62374172,62304242,62304240,62404241)+4 种基金Youth Innovation Promotion Association of CAS(Grant Nos.2022323 and 2022324)Key R&D Program of Jiangsu Province(Grant No.BE2023018-2)Basic Research Program of Jiangsu(Grant No.BK20240126)Suzhou Science and Technology Program(Grant Nos.SYC2022089,ZXL2024379,and ZXL2024376)Guangdong Basic and Applied Basic Research Foundation(Grant Nos.2022A1515110482 and 2022A1515110004).
文摘Photonic crystal surface emitting lasers(PCSELs)utilize the Bragg diffraction of two-dimensional photonic crystals to achieve a single-mode output with a high power and a small divergence angle,and has recently attracted much attention^([1−3]).In 2023,Kyoto University reported GaAs-based 945 nm PCSELs with a continuous-wave(CW)single-mode output power of exceeding 50 W,and a narrow beam divergence angle of 0.05°,demonstrating a brightness of 1 GW·cm^(−2)·sr^(−1),which rivals those of the existing bulky lasers^([4]).
基金supported by the National Natural Science Foundation of China (51320105001, 51372190, 21573170, 51272199, 21433007)the National Basic Research Program of China (973 program, 2013CB632402)+2 种基金the Natural Science Foundation of Hubei Province (2015CFA001)the Fundamental Research Funds for the Central Universities (WUT: 2015-Ⅲ-034)Innovative Research Funds of SKLWUT (2015-ZD-1)~~
文摘Flower-like tin oxide-supported platinum（Pt/SnOx） with a hierarchical structure was synthesized by a hydrothermal method and characterized by XRD,SEM,TEM,high resolution TEM,XPS and nitrogen adsorption.The flower-like Pt/SnOx microspheres of 1 μm in diameter were composed of staggered petal-like nanosheets with a thickness of 20 nm.Pt nanoparticles（NPs） of 2-3 nm were well dispersed on the SnOx nanosheets.The catalyst was tested in the catalytic oxidation of gaseous formaldehyde（HCHO） at room temperature,and exhibited enhanced activity compared to Pt NPs supported on commercial SnO and ground SnOx.HCHO removal of 87%was achieved over the hierarchical Pt/SnOx after 1 h of reaction,which was 1.5 times that over the ground SnOx-supported Pt（Pt/g-SnOx）,and the high activity was maintained after six recycles,showing the high stability of this catalyst.HCHO decomposition kinetics was modeled as a second order reaction.The reaction rate constant for Pt/SnOx was 5.6 times higher than Pt/g-SnOx.The hierarchical pore structure was beneficial for the diffusion and adsorption of HCHO molecules,and the highly dispersed Pt NPs on the SnOx nanosheets were the active sites for the oxidative decomposition of HCHO into CO2 and H2O.This study provided a promising approach for designing efficient catalysts for indoor HCHO removal at ambient temperature.
基金financially supported by the National Natural Science Foundation of China (No. 21734007)Tianjin government
文摘Room temperature phosphorescence(RTP) has drawn increasing attention for its great potential in practical applications.Polymers with large molecular weights and long chains tend to form coil, which can endow them with a high degree of possible rigidity and result in the much restricted non-radiative transition. Also, the intertwined structure of polymers could isolate the oxygen and humidity effectively, thus reducing the consumption of triplet excitons. In consideration of these points, organic polymers would be another kind of ideal platform to realize RTP effect. This short review summarized the design strategy of the purely organic room temperature phosphorescence polymers, mainly focusing on the building forms of polymers and the corresponding inherent mechanisms,and also gives some outlooks on the further exploration of this field at the end of this paper.
基金the Guangdong Province Science and Technology projects(No.2017A040402005)Guangdong Bureau of Quality and Technical Supervision Science and Technology projects(No.2017CT30)for financial support of this work
文摘The SiO_2 nanoparticles were coated on the surface of graphene oxide(GO) by sol-gel method to get the SiO_2-G compound.The SiO_2-G was restored and oleophylically modified to prepare hydrophobic modified SiO_2-G(HM-SiO_2-G) which was subsequently added to silicone rubber matrix to prepare two-component room temperature vulcanized(RTV-2) thermal conductive silicone rubber. The morphology, chemical structure and dispersity of the modified graphene were characterized with SEM, FTIR, Raman, and XPS methods.In addition, the heat-resistance behavior, mechanical properties, thermal conductivity, and electrical conductivity of the RTV-2 silicone rubber were also studied systematically. The results showed that the SiO_2 nanoparticles were coated on graphene oxide successfully, and HM-SiO_2-G was uniformly dispersed in RTV-2 silicone rubber. The addition of HM-SiO_2-G could effectively improve the thermal stability, mechanical properties and thermal conductivity of RTV-2 silicone rubber and had no great influence on the electrical insulation performance.
基金Supported by the National Nature Science Foundation of China(No.21476177)
文摘A serial of ordered meso-macroporous phosphotungstic acid(HPW) supported on SiO2 nanocomposites were successfully prepared by a homogeneous precipitation method, using monodispersed polystyrene(PS) microspheres and cationic surfactant as structure directing agent. These nanocomposites were used as catalysts for oxidative desulfurization(ODS) of model fuel. The materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), N2 adsorption-desorption isothrem, X-ray diffraction(XRD), and Fourier transform infrared spectra(FTIR). The characterization results suggested that the as-prepared material possessed ordered meso-macroporous architectures with Keggin type phosphotungstic acid dispersed homogeneously in SiO2 matrix. Under the selected reaction conditions, dibenzothiophene(DBT) in model fuel can be removed within 2 h at room temperature(30 ℃). In addition, only 1.2% of efficiency lose than the fresh catalyst even after 5 cycles.
基金This project was supported financially by the "863"project Ministry of Science and Technology(2002AA324010).
文摘A reciprocating magnetic refrigerator was developed based on the active magnetic regeneration technology. Rare earth metal Gd and intermetallic compound LaFe11.2Co0.7Si1.1 were used as the magnetic operating materials in the machine. The particles of the magnetic operating materials, with diameter of 0.5-2 mm and total mass of 950 g, were mounted in the cooling bed. A magnetic field was assembled using NdFeB rare earth permanent magnets. It had the magnetic field space of Φ 34×200 and the magnetic induction of 1.5 T. The water at pH=10 is used as a heat transfer fluid. When the ambient temperature is 296 K, a temperature span of 18 K was achieved after operation of 45 min at a frequency of 0.178 Hz. The temperature span and the output power increase significantly with the increasing velocity of heat transfer.
基金supported by the Natural Sci-ence Foundation of Guangxi Province, China (No. 0640009)
文摘Nano-sized cerium-titanium pyrophosphates Ce1-xTixP2O7 （with x = 0, 0.2, 0.5, 0.7, 0.9, and 1.0） were obtained by grinding a mixture of Ce（SO4）2·4H2O, Ti（SO4）2, and Na4P2O7·10H2O in the presence of surfactant PEG-400 at room temperature, washing the mixture with water to remove soluble inorganic salts, and drying at 100℃. The products and their calcined samples were characterized using ultraviolet-visible spectroscopy （UV-vis）, thermogravimetry and differential thermal analyses （TG/DTA）, X-ray powder diffraction （XRD）, and transmission electron microscopy （TEM）. The results show that nano-sized Ce1-xTixP2O7 behave as an excellent UV-shielding material. Thereinto, the CeP2O7 has the most excellent UV-shielding effect, and the amorphous state of Ce0.8Ti0.2P2O7 can keep at a higher temperature than CeP2O7. Therefore, the stabilization of the amorphous state of the cerium pyrophosphates was carded out by doping titanium. This stabilization is a significant improvement, which enables to apply these amorphous pyrophosphates not only to cosmetics and paints, but also plastics and films.
基金supported by the National Natural Science Foundation of China(NSFC,Nos.21333003,21622305)National Ten Thousand Talent Program for Young Top-notch Talents in ChinaThe Shanghai Shuguang Scholar Program(No.17SG30)
文摘The NO oxidation processes on CrO_2(110) was investigated by virtue of DFT + U calculation together with microkinetic analysis, aiming to uncover the reaction mechanism and activity-limiting factors for CrO_2 catalyst. It was found that NO oxidation on CrO_2(110) has to be triggered with the lattice Obri involved(Mars-van Krevelen mechanism) rather than the Langmuir-Hinshelwood path occurring at the Cr_(5 c) sites alone. Specifically, the optimal reaction path was identified. Quantitatively, the microkinetic analysis showed that CrO_2(110) can exhibit a high turnover rate of 0.978 s^(-1) for NO oxidation at room temperature.Such an activity could originate from the bifunctional synergetic catalytic mechanism, in which the Cr_(5c)sites can exclusively adsorb NO and the Obri is very reactive and provides oxidative species. However, it is worth noting that, as the reactive Obri tightly binds NO_2, the nitrate species was found to be difficult removed and constituted the key poisoning species, eventually limiting the overall activity of CrO_2. This work demonstrated the considerable catalytic ability of CrO_2 for NO oxidation at room temperature, and the understanding may facilitate the further design of more active Cr-based catalyst.
基金support by the Awarding Foundation for Middle and Young-Age Scientist of Shandong Province(2005).
文摘Uniform CeVO4 nanowires with diameter of about 25 nm were synthesized by the water-in-oil microemulsion method at room temperature from cerous chloride, sodium orthophosphate, sodium chloride, cyclohexane, Triton X-100 and cetyltrimethyl ammonium bromide （CTAB）. The crystal structure and morphology of the nanowires were characterized by XRD and TEM, respectively. The UV-vis absorption was detected by UV-vis spectrophotometer techniques. The results showed that as-prepared nanowires with the hexagonal phase have obvious quantum confinement effect and semiconductor characteristics. Little sodium chloride could play a positive role on the formation of CePO4 nanowires at room temperature. The size of the nanowires can be controlled through the joining of sodium chloride. C 2009 Yi Bin Yin. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
