Zn-N_(2)batteries,which are comprised of nitrogen reduction reaction(NRR)and oxygen evolution reaction(OER),represent an emerging technology for efficient ammonia production and simultaneous power generation.Neverthel...Zn-N_(2)batteries,which are comprised of nitrogen reduction reaction(NRR)and oxygen evolution reaction(OER),represent an emerging technology for efficient ammonia production and simultaneous power generation.Nevertheless,the intrinsic limitations of NRR and OER currently preclude its advancement.In this paper,Co and B co-doped Lavoisier framework series materials(MIL)are synthesized.Rapid mass transfer is rendered feasible with B_(0.25)-MIL-88-Fe_(4)Co_(1) by the distinctive double cone microrods structure.The addition of soft acid metal node Co^(2+)and B with defective electronic structure modifies the electronic configuration of MIL-88-Fe.At the same time,doping causes defects in the metal-organic frameworks,expands effectively the pore size,and increases the specific surface area,thereby expediting the adsorption of N_(2)and the release of O_(2).The electrocatalysis results show that the dual-doping scheme increases the NH_(3)yield(127.27μg^(-1)h^(-1)mg_(cat)^(-1))and Faraday efficiency(25.81%)while reducing the overpotential of OER(330 mV),achieving a power density of 8.30 mW cm^(-2)for Zn-N_(2)batteries.This discovery implements another avenue for the exploration of Zn-N_(2)battery materials and holds broader significance for advancing the field of energy storage and conversion.展开更多
For static magnetic properties of the Co/Ni bilayers,macroscopic hysteresis loops and microscopic magnetic moment distributions have been determined by the object oriented micromagnetic framework(OOMMF).It is found th...For static magnetic properties of the Co/Ni bilayers,macroscopic hysteresis loops and microscopic magnetic moment distributions have been determined by the object oriented micromagnetic framework(OOMMF).It is found that when the bilayer systems are fully decoupled,the magnetizations of the two phases reverse separately.The coercivity of the bilayers decreases to a valley value sharply with increasing interfacial exchange coupling and then rises slowly to a platform.On the other hand,we have carried out an atomistic simulation for the laser-induced ultrafast demagnetization of the Co/Ni bilayer.A larger damping constant leads to a faster demagnetization as well as a larger degree of demagnetization,which is consistent with the first-principle theoretical results.For the magnetization recovery process,the damping constant has different influences on the recovery time with various peak electron temperatures,which is ignored in previous atomistic simulations as well as the Landau–Liftshit–Bloch(LLB)micromagnetic calculations.Furthermore,as the interfacial exchange coupling increases,the ultrafast demagnetization curves for Co and Ni become coincident,which is a demonstration for the transition from two-phase phenomenon to single-phase phenomenon.展开更多
A compact surface plasmon resonance(SPR) fiber optic sensor, being utilized to simultaneously measure refractive index(RI) and temperature, is proposed and experimentally demonstrated in this paper. One part of a no-c...A compact surface plasmon resonance(SPR) fiber optic sensor, being utilized to simultaneously measure refractive index(RI) and temperature, is proposed and experimentally demonstrated in this paper. One part of a no-core fiber(NCF)was coated with a silver(Ag) film, and the other part was coated with a silver/polydimethylsiloxane(Ag/PDMS) composite film to stimulate the SPR effect. Due to the two heterogeneous films, two dips appeared in the transmission spectrum and were used to achieve the dual-parameter measurements. The experimental results showed that the RI sensitivity reached 2121.43 nm/RIU and 0 nm/RIU, while the temperature sensitivity reached-0.32 nm/℃ and-2.21 nm/℃ for the two dips,respectively. Based on the obtained transfer matrix, the measurements of RI and temperature could be demodulated. This designed sensor showed the merits of simple structure, easy to implement, and high sensitivity, demonstrating application prospects in dual-parameter monitoring.展开更多
Spin-valley polarization and bandgap regulation are critical in the developing of quantum devices.Here,by employing the density functional theory,we investigate the effects of stacking form,thickness and magnetic mome...Spin-valley polarization and bandgap regulation are critical in the developing of quantum devices.Here,by employing the density functional theory,we investigate the effects of stacking form,thickness and magnetic moment in the electronic structures of WSe_(2)–MoS_(2)heterostructures.Calculations show that spin-valley polarization maintains in all situations.Increasing thickness of 2H-MoS_(2)not only tunes the bandgap but also changes the degeneracy of the conduction band minimums(CBM)at K/K_(1) points.Gradual increase of micro magnetic moment tunes the bandgap and raises the valence band maximums(VBM)atΓpoint.In addition,the regulation of band gap by the thickness of 2H-MoS_(2)and introduced magnetic moment depends on the stacking type.Results suggest that WSe_(2)–MoS_(2)heterostructure supports an ideal platform for valleytronics applications.Our methods also give new ways of optical absorption regulation in spin-valley devices.展开更多
Thin films of millimeter-scale continuous monolayer WS_(2) have been grown on SiO_(2)/Si substrate,followed by the deposition ofβ-In_(2)Se_(3) crystals on monolayer WS2 to prepare In_(2)Se_(3)/WS_(2) van deWaals hete...Thin films of millimeter-scale continuous monolayer WS_(2) have been grown on SiO_(2)/Si substrate,followed by the deposition ofβ-In_(2)Se_(3) crystals on monolayer WS2 to prepare In_(2)Se_(3)/WS_(2) van deWaals heterostructures by a two-step chemical vapor deposition(CVD)method.After the growth of In_(2)Se_(3) at elevated temperatures,high densities of In_(2)Se_(3)/WS_(2) heterostructure bubbles with monolayer to multilayerβ-In_(2)Se_(3) crystals atop are observed.Fluorescence of the resultantβ-In_(2)Se_(3)/WS_(2) heterostructure is greatly enhanced in intensity upon the formation of bubbles,which are evidenced by the Newton’s rings in optical image owing to constructive and destructive interference.In photoluminescence(PL)mapping images of monolayerβ-In_(2)Se_(3)/monolayer WS2 heterobilayer bubble,significant oscillatory behavior of emission intensity is demonstrated due to constructive and destructive interference.However,oscillatory behaviors of peak position are also observed and come from a local heating effect induced by an excitation laser beam.The oscillatory mechanism of PL is further verified by changing the exterior pressure of bubbles placed in a home-made vacuum chamber.In addition,redshifted in peak position and broadening in peak width are observed due to strain effect during decreasing the exterior pressure of bubbles.展开更多
A high sensitivity plasmonic temperature sensor based on a side-polished photonic crystal fiber is proposed in this work.In order to achieve high sensitivity and high stability,the gold layer is coated on the side-pol...A high sensitivity plasmonic temperature sensor based on a side-polished photonic crystal fiber is proposed in this work.In order to achieve high sensitivity and high stability,the gold layer is coated on the side-polished photonic crystal fiber to support surface plasmon resonance.The mixture of ethanol and chloroform is used as the thermosensitive liquid.The performances of the proposed temperature sensor were investigated by the finite element method(FEM).Simulation results indicate that the sensitivity of the temperature sensor is as high as 7.82 nm/℃.It has good linearity(R;=0.99803),the resolution of 1.1×10;℃,and the amplitude sensitivity of 0.1008℃;.In addition,the sizes of the small air hole and polishing depth have little influence on the sensitivity.Therefore,the proposed sensor shows a high structure tolerance.The excellent performance and high structure tolerance of the sensor make it an appropriate choice for temperature measurement.展开更多
基金supported by the Special Project for Local Science and Technology Development Guided by the Central Government of China(No.236Z1406G)。
文摘Zn-N_(2)batteries,which are comprised of nitrogen reduction reaction(NRR)and oxygen evolution reaction(OER),represent an emerging technology for efficient ammonia production and simultaneous power generation.Nevertheless,the intrinsic limitations of NRR and OER currently preclude its advancement.In this paper,Co and B co-doped Lavoisier framework series materials(MIL)are synthesized.Rapid mass transfer is rendered feasible with B_(0.25)-MIL-88-Fe_(4)Co_(1) by the distinctive double cone microrods structure.The addition of soft acid metal node Co^(2+)and B with defective electronic structure modifies the electronic configuration of MIL-88-Fe.At the same time,doping causes defects in the metal-organic frameworks,expands effectively the pore size,and increases the specific surface area,thereby expediting the adsorption of N_(2)and the release of O_(2).The electrocatalysis results show that the dual-doping scheme increases the NH_(3)yield(127.27μg^(-1)h^(-1)mg_(cat)^(-1))and Faraday efficiency(25.81%)while reducing the overpotential of OER(330 mV),achieving a power density of 8.30 mW cm^(-2)for Zn-N_(2)batteries.This discovery implements another avenue for the exploration of Zn-N_(2)battery materials and holds broader significance for advancing the field of energy storage and conversion.
基金Project supported by the National Basic Research Program of China(Grant Nos.2015CB921403 and 2016YFA0300701)the National Natural Science Foundation of China(Grant Nos.91622126,51427801,and 51671212)the Natural Science Foundation of Hebei Province,China(Grant No.A2015203021)
文摘For static magnetic properties of the Co/Ni bilayers,macroscopic hysteresis loops and microscopic magnetic moment distributions have been determined by the object oriented micromagnetic framework(OOMMF).It is found that when the bilayer systems are fully decoupled,the magnetizations of the two phases reverse separately.The coercivity of the bilayers decreases to a valley value sharply with increasing interfacial exchange coupling and then rises slowly to a platform.On the other hand,we have carried out an atomistic simulation for the laser-induced ultrafast demagnetization of the Co/Ni bilayer.A larger damping constant leads to a faster demagnetization as well as a larger degree of demagnetization,which is consistent with the first-principle theoretical results.For the magnetization recovery process,the damping constant has different influences on the recovery time with various peak electron temperatures,which is ignored in previous atomistic simulations as well as the Landau–Liftshit–Bloch(LLB)micromagnetic calculations.Furthermore,as the interfacial exchange coupling increases,the ultrafast demagnetization curves for Co and Ni become coincident,which is a demonstration for the transition from two-phase phenomenon to single-phase phenomenon.
基金the Natural Science Foundation of Hebei Province, China (Grant No. F2021203112)the National Natural Science Foundation of China (Grant No. 12074331)+1 种基金the National Key Research and Development Program of China (Grant No. 2019YFB2204001)Basic Scientific Research Funds for universities in Hebei Province, China (Grant No. JQN2021019)。
文摘A compact surface plasmon resonance(SPR) fiber optic sensor, being utilized to simultaneously measure refractive index(RI) and temperature, is proposed and experimentally demonstrated in this paper. One part of a no-core fiber(NCF)was coated with a silver(Ag) film, and the other part was coated with a silver/polydimethylsiloxane(Ag/PDMS) composite film to stimulate the SPR effect. Due to the two heterogeneous films, two dips appeared in the transmission spectrum and were used to achieve the dual-parameter measurements. The experimental results showed that the RI sensitivity reached 2121.43 nm/RIU and 0 nm/RIU, while the temperature sensitivity reached-0.32 nm/℃ and-2.21 nm/℃ for the two dips,respectively. Based on the obtained transfer matrix, the measurements of RI and temperature could be demodulated. This designed sensor showed the merits of simple structure, easy to implement, and high sensitivity, demonstrating application prospects in dual-parameter monitoring.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61975224 and 12104004)the University Synergy Innovation Program of Anhui Province(Grant No.GXXT-2020-050)+2 种基金the Fund of Anhui Provincial Natural Science Foundation(Grant No.2008085MF206)New magnetoelectric materials and devices,the Recruitment Program for Leading Talent Team of Anhui Province 2020,State Key Laboratory of Luminescence and Applications(Grant No.SKLA-2021-03)the Open Fund of Infrared and Low-Temperature Plasma Key Laboratory of Anhui Province(Grant No.IRKL2022KF03)。
文摘Spin-valley polarization and bandgap regulation are critical in the developing of quantum devices.Here,by employing the density functional theory,we investigate the effects of stacking form,thickness and magnetic moment in the electronic structures of WSe_(2)–MoS_(2)heterostructures.Calculations show that spin-valley polarization maintains in all situations.Increasing thickness of 2H-MoS_(2)not only tunes the bandgap but also changes the degeneracy of the conduction band minimums(CBM)at K/K_(1) points.Gradual increase of micro magnetic moment tunes the bandgap and raises the valence band maximums(VBM)atΓpoint.In addition,the regulation of band gap by the thickness of 2H-MoS_(2)and introduced magnetic moment depends on the stacking type.Results suggest that WSe_(2)–MoS_(2)heterostructure supports an ideal platform for valleytronics applications.Our methods also give new ways of optical absorption regulation in spin-valley devices.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51732010 and 51972280)the Natural Science Foundation of Hebei Province,China(Grant No.E2019203233)the Research Program of the College Science&Technology of Hebei Province,China(Grant No.ZD2020121).
文摘Thin films of millimeter-scale continuous monolayer WS_(2) have been grown on SiO_(2)/Si substrate,followed by the deposition ofβ-In_(2)Se_(3) crystals on monolayer WS2 to prepare In_(2)Se_(3)/WS_(2) van deWaals heterostructures by a two-step chemical vapor deposition(CVD)method.After the growth of In_(2)Se_(3) at elevated temperatures,high densities of In_(2)Se_(3)/WS_(2) heterostructure bubbles with monolayer to multilayerβ-In_(2)Se_(3) crystals atop are observed.Fluorescence of the resultantβ-In_(2)Se_(3)/WS_(2) heterostructure is greatly enhanced in intensity upon the formation of bubbles,which are evidenced by the Newton’s rings in optical image owing to constructive and destructive interference.In photoluminescence(PL)mapping images of monolayerβ-In_(2)Se_(3)/monolayer WS2 heterobilayer bubble,significant oscillatory behavior of emission intensity is demonstrated due to constructive and destructive interference.However,oscillatory behaviors of peak position are also observed and come from a local heating effect induced by an excitation laser beam.The oscillatory mechanism of PL is further verified by changing the exterior pressure of bubbles placed in a home-made vacuum chamber.In addition,redshifted in peak position and broadening in peak width are observed due to strain effect during decreasing the exterior pressure of bubbles.
基金supported by the National Natural Science Foundation of China(Grant No.12074331)the Natural Science Foundation of Hebei Province,China(Grant No.F2020203050)the Postdoctoral preferred funding research project of Hebei Province,China(Grant No.B2018003008)。
文摘A high sensitivity plasmonic temperature sensor based on a side-polished photonic crystal fiber is proposed in this work.In order to achieve high sensitivity and high stability,the gold layer is coated on the side-polished photonic crystal fiber to support surface plasmon resonance.The mixture of ethanol and chloroform is used as the thermosensitive liquid.The performances of the proposed temperature sensor were investigated by the finite element method(FEM).Simulation results indicate that the sensitivity of the temperature sensor is as high as 7.82 nm/℃.It has good linearity(R;=0.99803),the resolution of 1.1×10;℃,and the amplitude sensitivity of 0.1008℃;.In addition,the sizes of the small air hole and polishing depth have little influence on the sensitivity.Therefore,the proposed sensor shows a high structure tolerance.The excellent performance and high structure tolerance of the sensor make it an appropriate choice for temperature measurement.
