Poly(3-hexylthiophene)(P3HT)is one of the most promising hole-transporting materials in the pursuit of efficient and stable perovskite solar cells due to its outstanding stability and low cost.However,the intrinsic lo...Poly(3-hexylthiophene)(P3HT)is one of the most promising hole-transporting materials in the pursuit of efficient and stable perovskite solar cells due to its outstanding stability and low cost.However,the intrinsic low carrier density of P3 HT and poor contact between the P3HT/perovskite interface always lead to a low performance of the solar cell,while conventional chemical doping always makes the films unstable and limits the scalability.In this work,for the first time,we simultaneously enhanced the hole transporting properties of P3HT film and the interface of perovskite by doping it with a judiciously designed oxidized small molecule organic semiconductor.The organic salt not only can promote the lamellar crystallinity of P3HT to obtain better charge transport properties,but also reduce the defects of perovskite.As a result,we achieved champion efficiencies of 23.0%for small-area solar cells and 18.8%for larger-area modules(48.0 cm^(2)).This efficiency is the highest value for P3HT-based perovskite modules.Moreover,the solar cells show excellent operational stability,retaining over 95%of their initial efficiencies after1200 h of continuous operation.展开更多
The forward gated-diode R-G current method is used to monitor the F-N stressing-induced interface traps of NMOSFET/SOI.This simp le and accurate experiment method can directly give the interface trap density i nduced...The forward gated-diode R-G current method is used to monitor the F-N stressing-induced interface traps of NMOSFET/SOI.This simp le and accurate experiment method can directly give the interface trap density i nduced by F-N stressing effect for characterizing the device's reliability.For the measured NMOS/SOI device with a body structure,an expected power-law relati onship as Δ N it - t 0 4 between the pure F-N stressing-indu ced interface trap density and the accumulated stressing time is obtained.展开更多
The surface and interface electronic states of tris (8 hydroxyquinoline) aluminum (Alq 3)/indium tin oxide (ITO) were measured and analyzed by X ray photoelectron spectroscopy (XPS). The results indicated that, in Alq...The surface and interface electronic states of tris (8 hydroxyquinoline) aluminum (Alq 3)/indium tin oxide (ITO) were measured and analyzed by X ray photoelectron spectroscopy (XPS). The results indicated that, in Alq 3 molecule, the binding energy ( E b) of Al atoms is 70.7 eV and 75.1 eV, corresponding to Al(O) and Al(Ⅲ), respectively; The binding energy of C is 285.8 eV, 286.3 eV, and 286.8 eV, corresponding to C of C-C group, C-O, and C-N bond, respectively. N is the main peak locating at 401.0 eV, corresponding to N atom of C-N=C. O atoms mainly bond to H atom, with the binding energy of 533.2 eV. As the sputtering time of Ar + ion beam increases, Al 2p , C 1s , N 1s , O 1s , In 3d 5/2 and Sn 3d 5/2 peaks slightly shift towards lower binding energy, and Al 2p , C 1s and N 1s peaks get weaker, which contributes to diffusing the oxygen, indium and tin in ITO into Alq 3 layer.展开更多
Interface characteristics possess very important influence on the performance of thin film devices. ITO/ PTCDA/p-Si thin film device was set up with vacuum evaporation and sputter deposition method. The surface and in...Interface characteristics possess very important influence on the performance of thin film devices. ITO/ PTCDA/p-Si thin film device was set up with vacuum evaporation and sputter deposition method. The surface and interface electron states of ITO/PTCDA/p-Si were investigated by X-ray photoelectron spectroscopy （XPS） and argon ion beam etch techniques. Results indicate that at the interface of ITO/PTODA/p- Si,not only ITO/PTCDA-Si but also PDCDA-Si can produce diffusion. Moreover, the XPS spectra of each atom appear chemical shifts, and the chemical shifts of C1s and O1s are more remarkable.展开更多
An Fe-0.2C-1.5Si-1.67Mn steel was subjected to quenching and partitioning （Q＆P） process, and the interface migration between martensite and austenite at an elevated partitioning temperature was observed. The interf...An Fe-0.2C-1.5Si-1.67Mn steel was subjected to quenching and partitioning （Q＆P） process, and the interface migration between martensite and austenite at an elevated partitioning temperature was observed. The interface migration is excluded in constrained paraequilibrium （CPE） model. Based on ＂endpoint＂ predicted by CPE model the thermodynamic condition of interface migration is analyzed, that is, the difference in the chemical potential of iron in both ferrite （martenisite） and austenite produces the driving force of the iron atoms to migrate from one phase to the other phase. In addition, the interface migration can change the austenite fraction; as a result, the austenite fraction at partitioning temperature may be higher than that at quenching temperature through the interface migration, but this phenomenon cannot be explained by CPE model.展开更多
Brain-Computer interfacing(BCI)has currently added a new dimension in assistive robotics.Existing braincomputer interfaces designed for position control applications suffer from two fundamental limitations.First,most ...Brain-Computer interfacing(BCI)has currently added a new dimension in assistive robotics.Existing braincomputer interfaces designed for position control applications suffer from two fundamental limitations.First,most of the existing schemes employ open-loop control,and thus are unable to track positional errors,resulting in failures in taking necessary online corrective actions.There are examples of a few works dealing with closed-loop electroencephalography(EEG)-based position control.These existing closed-loop brain-induced position control schemes employ a fixed order link selection rule,which often creates a bottleneck preventing time-efficient control.Second,the existing brain-induced position controllers are designed to generate a position response like a traditional firstorder system,resulting in a large steady-state error.This paper overcomes the above two limitations by keeping provisions for steady-state visual evoked potential(SSVEP)induced linkselection in an arbitrary order as required for efficient control and generating a second-order response of the position-control system with gradually diminishing overshoots/undershoots to reduce steady-state errors.Other than the above,the third innovation is to utilize motor imagery and P300 signals to design the hybrid brain-computer interfacing system for the said application with gradually diminishing error-margin using speed reversal at the zero-crossings of positional errors.Experiments undertaken reveal that the steady-state error is reduced to 0.2%.The paper also provides a thorough analysis of the stability of the closed-loop system performance using the Root Locus technique.展开更多
The microstructural characteristic of 1070AI matrix composites reinforced by 0.15 祄 AI2O3 particles whose volume fraction was 40% was investigated by TEM and HREM. The results showed that the interface between the ma...The microstructural characteristic of 1070AI matrix composites reinforced by 0.15 祄 AI2O3 particles whose volume fraction was 40% was investigated by TEM and HREM. The results showed that the interface between the matrix and reinforcements was clean and bonded well, without any interfacial reaction products. There were some preferential crystallographic orientation relationships between Al matrix and AI2O3 particle because of the lattice imperfection on the surface of Al2O3 particles.展开更多
The lowest order Pl-nonconforming triangular finite element method （FEM） for elliptic and parabolic interface problems is investigated. Under some reasonable regularity assumptions on the exact solutions, the optima...The lowest order Pl-nonconforming triangular finite element method （FEM） for elliptic and parabolic interface problems is investigated. Under some reasonable regularity assumptions on the exact solutions, the optimal order error estimates are obtained in the broken energy norm. Finally, some numerical results are provided to verify the theoretical analysis.展开更多
The direct conversion of atmospheric CO_(2) into fuel via photocatalysis exhibits significant practical application value in advancing the carbon cycle.In this study,we established an electro-assisted photocatalytic s...The direct conversion of atmospheric CO_(2) into fuel via photocatalysis exhibits significant practical application value in advancing the carbon cycle.In this study,we established an electro-assisted photocatalytic system with dual compartments and interfaces,and coated Ag nanoparticles on the titanium nanotube arrays(TNTAs)by polydopamine modification.In the absence of sacrificial agent and alkali absorption liquid conditions,the stable,efficient and highly selective conversion of CO_(2) to CO at the gas-solid interface in ambient air was realized by photoelectric synergy.Specifically,with the assistance of potential,the CO formation rates reached 194.9μmol h^(−1) m^(−2) and 103.9μmol h^(−1) m^(−2) under ultraviolet and visible light irradiation,respectively;the corresponding CO_(2) conversion rates in ambient air were 30%and 16%,respectively.The excellent catalytic effect is mainly attributed to the formation of P–N heterojunction during the catalytic process and the surface plasmon resonance effect.Additionally,the introduction of solid agar electrolytes effectively inhibits the hydrogen evolution reaction and improves the electron utilization rate.This system promotes the development of photocatalytic technology for practical applications and provides new insights and support for the carbon cycle.展开更多
Brain–computer interface (BCI) systems, such as the P300 speller, enable patients to express intentions withoutnecessitating extensive training.However, the complexity of operational instructions and the slow pace of...Brain–computer interface (BCI) systems, such as the P300 speller, enable patients to express intentions withoutnecessitating extensive training.However, the complexity of operational instructions and the slow pace of characterspelling pose challenges for some patients. In this paper, an image segmentation P300 selector based on YOLOv7-mask and DeepSORT is proposed. The proposed system utilizes a camera to capture real-world objects forclassification and tracking. By applying predefined stimulation rules and object-specificmasks, the proposed systemtriggers stimuli associated with the objects displayed on the screen, inducing the generation of P300 signals in thepatient’s brain. Its video processing mechanism enables the system to identify the target the patient is focusing oneven if the object is partially obscured, overlapped, moving, or changing in number. The system alters the target’scolor display, thereby conveying the patient’s intentions to caregivers. The data analysis revealed that the selfrecognitionaccuracy of the subjects using this method was between 92% and 100%, and the cross-subject P300recognition precision was 81.9%–92.1%. This means that simple instructions such as “Do not worry, just focuson what you desire” effectively discerned the patient’s intentions using the Image Segmentation-P300 selector. Thisapproach provides cost-effective support and allows patients with communication difficulties to easily express theirneeds.展开更多
The tactile P300 brain-computer interface( BCI) is related to the somatosensory perception and response of the human brain,and is different from visual or audio BCIs. Recently,several studies focused on the tactile st...The tactile P300 brain-computer interface( BCI) is related to the somatosensory perception and response of the human brain,and is different from visual or audio BCIs. Recently,several studies focused on the tactile stimuli delivered to different parts of the human body. Most of these stimuli were symmetrically bilateral.Only a fewstudies explored the influence of tactile stimuli laterality.In the current study,we extensively tested the performance of a vibrotactile BCI system using ipsilateral stimuli and bilateral stimuli.Two vibrotactile P300-based paradigms were tested. The target stimuli were located on the left and right forearms for the left forearm and right forearm( LFRF) paradigm,and on the left forearm and calf for the left forearm and left calf( LFLC)paradigm. Ten healthy subjects participated in this study. Our experiments and analysis showed that the bilateral paradigm( LFRF) elicited larger P300 amplitude and achieved significantly higher classification accuracy than the ipsilateral paradigm( LFLC). However, both paradigms achieved classification accuracies higher than 70% after the completion of several trials on average,which was usually regarded as the minimum accuracy level required for BCI system to be deemed useful.展开更多
Design of the catalyst for efficient water dissociation and hydrogen recombination is paramount in enhancement of the alkaline water electrolysis kinetics.Herein,we reported a delicate hierarchical(VO)_(2) P_(2)O_(7)-...Design of the catalyst for efficient water dissociation and hydrogen recombination is paramount in enhancement of the alkaline water electrolysis kinetics.Herein,we reported a delicate hierarchical(VO)_(2) P_(2)O_(7)-Ni_(2) P@NF(VPO-Ni_(2) P@NF)hybrid catalyst that operated efficiently in alkaline media.The VPO and Ni_(2) P respectively act as the water dissociation promoter and the hydrogen recombination center,which synergistically propel water adsorption/dissociation and H intermediates recombination.The resulting synergistic interfaces between VPO and Ni_(2) P are verified to afford the catalyst an outstanding performance for hydrogen evolution reaction in alkaline media with an overpotential of 154 mV at 10 mA cm^(-2),Tafel slope of 65 mV dec^(-1),and remarkable durability.Furthermore,the catalyst presents the potential for overall water splitting.This work may shed fresh light on the high-performance electrocatalyst design and the application of VPO on water electrolysis.展开更多
ZnO micro-prisms are prepared on the p-type and n-type Si substrates, separately. The Ⅰ-Ⅴ curves analysed by AFM show that the interface junctions between the ZnO micro-prisms and the p-type substrate and between th...ZnO micro-prisms are prepared on the p-type and n-type Si substrates, separately. The Ⅰ-Ⅴ curves analysed by AFM show that the interface junctions between the ZnO micro-prisms and the p-type substrate and between the ZnO micro-prisms and the n-type Si substrate exhibit p-n junction behaviour and ohmic contuct behuviour, respectively. The formation of the p-n heterojunction and ohmic contact is ascribed to the intrinsic n-type conduction of ZnO material. Better field emission performance （lower onset voltage and larger emission current） is observed from an individual ZnO micro-prism grown on the n-type Si substrate. It is suggested that the n-Si/n-ZnO interracial ohmic contact benefits the electron emission; while the p-Si/n-ZnO interface heterojunction deteriorates the electron emission.展开更多
Layered oxides present compelling potential as cathode materials for sodium-ion batteries(SIBs).However,challenges including interfacial instability and sluggish reaction kinetics critically limit their rate capabilit...Layered oxides present compelling potential as cathode materials for sodium-ion batteries(SIBs).However,challenges including interfacial instability and sluggish reaction kinetics critically limit their rate capability and cycling performance.Herein,we introduce the water-soluble sodium polyacrylate(NaPAA)binder as a promising approach to mitigating these issues in P2-type layered oxides.The NaPAA binder facilitates the formation of a uniform Na^(+) conductive interfacial film,which protects the cathode against electrolyte-induced corrosion and effectively inhibits the dissolution of transition metals in P2-Na_(0.85)Li_(0.12)Ni_(0.22)Mn_(0.66)O_(2)(NLNMO).Furthermore,we elucidate the mechanism by which the NaPAA binder dynamically regulates the coordination of free anions at the electrode-electrolyte interface.This regulation reduces solvent decomposition and promotes the formation of a stable,ionically conductive layer.Consequently,the P2-NLNMO@NaPAA integrated electrode exhibits enhanced electrochemical performance,achieving an 89.2%capacity retention after 200 cycles at 0.2 C and delivering an initial capacity of 102.9 mA h g^(-1) even at 0℃.This study advances the fundamental understanding of binder-mediated interface engineering and demonstrates a scalable and eco-friendly manufacturing pathway for high-performance SIBs.展开更多
We analyzed the structure of buried interface of BBDMS PPV/ITO system using a high resolution ADXPS technique. A transitional layer structure, whose chemical composition, state and valence band changed gradually from ...We analyzed the structure of buried interface of BBDMS PPV/ITO system using a high resolution ADXPS technique. A transitional layer structure, whose chemical composition, state and valence band changed gradually from BBDMS PPV surface of film to substrate ITO, was observed. It was found that O 2- ion from ITO diffused into polymer film, interacted with back bone carbon and formed the carbonyl bonding which could possibly constructed the channel of the carrier on the heterointerface. Indium of ITO also diffused into BBDMS PPV layer and In(OH) 3 was formed during diffusion. The diffusion and reaction between PPV/ITO interface may affect the performance of PLED significantly.展开更多
基金financially supported by the National Natural Science Foundation of China(52472248 and 22075221)the Key Research and Development Project of Shanxi Province(202202060301003 and 202202060301015)the Innovation Program of Wuhan-Shuguang Project(2023010201020367)。
文摘Poly(3-hexylthiophene)(P3HT)is one of the most promising hole-transporting materials in the pursuit of efficient and stable perovskite solar cells due to its outstanding stability and low cost.However,the intrinsic low carrier density of P3 HT and poor contact between the P3HT/perovskite interface always lead to a low performance of the solar cell,while conventional chemical doping always makes the films unstable and limits the scalability.In this work,for the first time,we simultaneously enhanced the hole transporting properties of P3HT film and the interface of perovskite by doping it with a judiciously designed oxidized small molecule organic semiconductor.The organic salt not only can promote the lamellar crystallinity of P3HT to obtain better charge transport properties,but also reduce the defects of perovskite.As a result,we achieved champion efficiencies of 23.0%for small-area solar cells and 18.8%for larger-area modules(48.0 cm^(2)).This efficiency is the highest value for P3HT-based perovskite modules.Moreover,the solar cells show excellent operational stability,retaining over 95%of their initial efficiencies after1200 h of continuous operation.
文摘The forward gated-diode R-G current method is used to monitor the F-N stressing-induced interface traps of NMOSFET/SOI.This simp le and accurate experiment method can directly give the interface trap density i nduced by F-N stressing effect for characterizing the device's reliability.For the measured NMOS/SOI device with a body structure,an expected power-law relati onship as Δ N it - t 0 4 between the pure F-N stressing-indu ced interface trap density and the accumulated stressing time is obtained.
文摘The surface and interface electronic states of tris (8 hydroxyquinoline) aluminum (Alq 3)/indium tin oxide (ITO) were measured and analyzed by X ray photoelectron spectroscopy (XPS). The results indicated that, in Alq 3 molecule, the binding energy ( E b) of Al atoms is 70.7 eV and 75.1 eV, corresponding to Al(O) and Al(Ⅲ), respectively; The binding energy of C is 285.8 eV, 286.3 eV, and 286.8 eV, corresponding to C of C-C group, C-O, and C-N bond, respectively. N is the main peak locating at 401.0 eV, corresponding to N atom of C-N=C. O atoms mainly bond to H atom, with the binding energy of 533.2 eV. As the sputtering time of Ar + ion beam increases, Al 2p , C 1s , N 1s , O 1s , In 3d 5/2 and Sn 3d 5/2 peaks slightly shift towards lower binding energy, and Al 2p , C 1s and N 1s peaks get weaker, which contributes to diffusing the oxygen, indium and tin in ITO into Alq 3 layer.
基金Project is supported by the National Natural Science Foundationof China (Grant No 60076023)
文摘Interface characteristics possess very important influence on the performance of thin film devices. ITO/ PTCDA/p-Si thin film device was set up with vacuum evaporation and sputter deposition method. The surface and interface electron states of ITO/PTCDA/p-Si were investigated by X-ray photoelectron spectroscopy （XPS） and argon ion beam etch techniques. Results indicate that at the interface of ITO/PTODA/p- Si,not only ITO/PTCDA-Si but also PDCDA-Si can produce diffusion. Moreover, the XPS spectra of each atom appear chemical shifts, and the chemical shifts of C1s and O1s are more remarkable.
文摘An Fe-0.2C-1.5Si-1.67Mn steel was subjected to quenching and partitioning （Q＆P） process, and the interface migration between martensite and austenite at an elevated partitioning temperature was observed. The interface migration is excluded in constrained paraequilibrium （CPE） model. Based on ＂endpoint＂ predicted by CPE model the thermodynamic condition of interface migration is analyzed, that is, the difference in the chemical potential of iron in both ferrite （martenisite） and austenite produces the driving force of the iron atoms to migrate from one phase to the other phase. In addition, the interface migration can change the austenite fraction; as a result, the austenite fraction at partitioning temperature may be higher than that at quenching temperature through the interface migration, but this phenomenon cannot be explained by CPE model.
文摘Brain-Computer interfacing(BCI)has currently added a new dimension in assistive robotics.Existing braincomputer interfaces designed for position control applications suffer from two fundamental limitations.First,most of the existing schemes employ open-loop control,and thus are unable to track positional errors,resulting in failures in taking necessary online corrective actions.There are examples of a few works dealing with closed-loop electroencephalography(EEG)-based position control.These existing closed-loop brain-induced position control schemes employ a fixed order link selection rule,which often creates a bottleneck preventing time-efficient control.Second,the existing brain-induced position controllers are designed to generate a position response like a traditional firstorder system,resulting in a large steady-state error.This paper overcomes the above two limitations by keeping provisions for steady-state visual evoked potential(SSVEP)induced linkselection in an arbitrary order as required for efficient control and generating a second-order response of the position-control system with gradually diminishing overshoots/undershoots to reduce steady-state errors.Other than the above,the third innovation is to utilize motor imagery and P300 signals to design the hybrid brain-computer interfacing system for the said application with gradually diminishing error-margin using speed reversal at the zero-crossings of positional errors.Experiments undertaken reveal that the steady-state error is reduced to 0.2%.The paper also provides a thorough analysis of the stability of the closed-loop system performance using the Root Locus technique.
基金This research is supported by the National Natural Science Foundation of China (under Grant No.59771014 and No.50071019). The help of the National Advanced Material Open Research Lab of Tsinghua University is gratefully acknowledged.
文摘The microstructural characteristic of 1070AI matrix composites reinforced by 0.15 祄 AI2O3 particles whose volume fraction was 40% was investigated by TEM and HREM. The results showed that the interface between the matrix and reinforcements was clean and bonded well, without any interfacial reaction products. There were some preferential crystallographic orientation relationships between Al matrix and AI2O3 particle because of the lattice imperfection on the surface of Al2O3 particles.
基金Project supported by the National Natural Science Foundation of China(No.11271340)
文摘The lowest order Pl-nonconforming triangular finite element method （FEM） for elliptic and parabolic interface problems is investigated. Under some reasonable regularity assumptions on the exact solutions, the optimal order error estimates are obtained in the broken energy norm. Finally, some numerical results are provided to verify the theoretical analysis.
文摘The direct conversion of atmospheric CO_(2) into fuel via photocatalysis exhibits significant practical application value in advancing the carbon cycle.In this study,we established an electro-assisted photocatalytic system with dual compartments and interfaces,and coated Ag nanoparticles on the titanium nanotube arrays(TNTAs)by polydopamine modification.In the absence of sacrificial agent and alkali absorption liquid conditions,the stable,efficient and highly selective conversion of CO_(2) to CO at the gas-solid interface in ambient air was realized by photoelectric synergy.Specifically,with the assistance of potential,the CO formation rates reached 194.9μmol h^(−1) m^(−2) and 103.9μmol h^(−1) m^(−2) under ultraviolet and visible light irradiation,respectively;the corresponding CO_(2) conversion rates in ambient air were 30%and 16%,respectively.The excellent catalytic effect is mainly attributed to the formation of P–N heterojunction during the catalytic process and the surface plasmon resonance effect.Additionally,the introduction of solid agar electrolytes effectively inhibits the hydrogen evolution reaction and improves the electron utilization rate.This system promotes the development of photocatalytic technology for practical applications and provides new insights and support for the carbon cycle.
文摘Brain–computer interface (BCI) systems, such as the P300 speller, enable patients to express intentions withoutnecessitating extensive training.However, the complexity of operational instructions and the slow pace of characterspelling pose challenges for some patients. In this paper, an image segmentation P300 selector based on YOLOv7-mask and DeepSORT is proposed. The proposed system utilizes a camera to capture real-world objects forclassification and tracking. By applying predefined stimulation rules and object-specificmasks, the proposed systemtriggers stimuli associated with the objects displayed on the screen, inducing the generation of P300 signals in thepatient’s brain. Its video processing mechanism enables the system to identify the target the patient is focusing oneven if the object is partially obscured, overlapped, moving, or changing in number. The system alters the target’scolor display, thereby conveying the patient’s intentions to caregivers. The data analysis revealed that the selfrecognitionaccuracy of the subjects using this method was between 92% and 100%, and the cross-subject P300recognition precision was 81.9%–92.1%. This means that simple instructions such as “Do not worry, just focuson what you desire” effectively discerned the patient’s intentions using the Image Segmentation-P300 selector. Thisapproach provides cost-effective support and allows patients with communication difficulties to easily express theirneeds.
基金National Key Research and Development Program,China(No.2017YFB13003002)National Natural Science Foundation of China(Nos.61573142,61773164,91420302)Programme of Introducing Talents of Discipline to Universities(the 111 Project)(No.B17017)
文摘The tactile P300 brain-computer interface( BCI) is related to the somatosensory perception and response of the human brain,and is different from visual or audio BCIs. Recently,several studies focused on the tactile stimuli delivered to different parts of the human body. Most of these stimuli were symmetrically bilateral.Only a fewstudies explored the influence of tactile stimuli laterality.In the current study,we extensively tested the performance of a vibrotactile BCI system using ipsilateral stimuli and bilateral stimuli.Two vibrotactile P300-based paradigms were tested. The target stimuli were located on the left and right forearms for the left forearm and right forearm( LFRF) paradigm,and on the left forearm and calf for the left forearm and left calf( LFLC)paradigm. Ten healthy subjects participated in this study. Our experiments and analysis showed that the bilateral paradigm( LFRF) elicited larger P300 amplitude and achieved significantly higher classification accuracy than the ipsilateral paradigm( LFLC). However, both paradigms achieved classification accuracies higher than 70% after the completion of several trials on average,which was usually regarded as the minimum accuracy level required for BCI system to be deemed useful.
基金supported by the National Natural Science Foundation of China(No.51902232)。
文摘Design of the catalyst for efficient water dissociation and hydrogen recombination is paramount in enhancement of the alkaline water electrolysis kinetics.Herein,we reported a delicate hierarchical(VO)_(2) P_(2)O_(7)-Ni_(2) P@NF(VPO-Ni_(2) P@NF)hybrid catalyst that operated efficiently in alkaline media.The VPO and Ni_(2) P respectively act as the water dissociation promoter and the hydrogen recombination center,which synergistically propel water adsorption/dissociation and H intermediates recombination.The resulting synergistic interfaces between VPO and Ni_(2) P are verified to afford the catalyst an outstanding performance for hydrogen evolution reaction in alkaline media with an overpotential of 154 mV at 10 mA cm^(-2),Tafel slope of 65 mV dec^(-1),and remarkable durability.Furthermore,the catalyst presents the potential for overall water splitting.This work may shed fresh light on the high-performance electrocatalyst design and the application of VPO on water electrolysis.
文摘ZnO micro-prisms are prepared on the p-type and n-type Si substrates, separately. The Ⅰ-Ⅴ curves analysed by AFM show that the interface junctions between the ZnO micro-prisms and the p-type substrate and between the ZnO micro-prisms and the n-type Si substrate exhibit p-n junction behaviour and ohmic contuct behuviour, respectively. The formation of the p-n heterojunction and ohmic contact is ascribed to the intrinsic n-type conduction of ZnO material. Better field emission performance （lower onset voltage and larger emission current） is observed from an individual ZnO micro-prism grown on the n-type Si substrate. It is suggested that the n-Si/n-ZnO interracial ohmic contact benefits the electron emission; while the p-Si/n-ZnO interface heterojunction deteriorates the electron emission.
基金supported by the National Natural Science Foundation of China(52374311)National Key R&D Program of China(2023YFE0203000)+3 种基金the National Natural Science Foundation of Shaanxi(2023KXJ-262,2025SYS-SYSZD-035)the Fund of the State Key Laboratory of Solidification Processing in NPU(2025-TS-10)the Fundamental Research Funds for the Central Universities(D5000250277)the Youth Innovation Team of Shaanxi Universities。
文摘Layered oxides present compelling potential as cathode materials for sodium-ion batteries(SIBs).However,challenges including interfacial instability and sluggish reaction kinetics critically limit their rate capability and cycling performance.Herein,we introduce the water-soluble sodium polyacrylate(NaPAA)binder as a promising approach to mitigating these issues in P2-type layered oxides.The NaPAA binder facilitates the formation of a uniform Na^(+) conductive interfacial film,which protects the cathode against electrolyte-induced corrosion and effectively inhibits the dissolution of transition metals in P2-Na_(0.85)Li_(0.12)Ni_(0.22)Mn_(0.66)O_(2)(NLNMO).Furthermore,we elucidate the mechanism by which the NaPAA binder dynamically regulates the coordination of free anions at the electrode-electrolyte interface.This regulation reduces solvent decomposition and promotes the formation of a stable,ionically conductive layer.Consequently,the P2-NLNMO@NaPAA integrated electrode exhibits enhanced electrochemical performance,achieving an 89.2%capacity retention after 200 cycles at 0.2 C and delivering an initial capacity of 102.9 mA h g^(-1) even at 0℃.This study advances the fundamental understanding of binder-mediated interface engineering and demonstrates a scalable and eco-friendly manufacturing pathway for high-performance SIBs.
文摘We analyzed the structure of buried interface of BBDMS PPV/ITO system using a high resolution ADXPS technique. A transitional layer structure, whose chemical composition, state and valence band changed gradually from BBDMS PPV surface of film to substrate ITO, was observed. It was found that O 2- ion from ITO diffused into polymer film, interacted with back bone carbon and formed the carbonyl bonding which could possibly constructed the channel of the carrier on the heterointerface. Indium of ITO also diffused into BBDMS PPV layer and In(OH) 3 was formed during diffusion. The diffusion and reaction between PPV/ITO interface may affect the performance of PLED significantly.
