Perovskite solar cells(PSCs)have emerged as promising photovoltaic technologies owing to their remarkable power conversion efficiency(PCE).However,heat accumulation under continuous illumination remains a critical bot...Perovskite solar cells(PSCs)have emerged as promising photovoltaic technologies owing to their remarkable power conversion efficiency(PCE).However,heat accumulation under continuous illumination remains a critical bottleneck,severely affecting device stability and long-term operational performance.Herein,we present a multifunctional strategy by incorporating highly thermally conductive Ti3C2TX MXene nanosheets into the perovskite layer to simultaneously enhance thermal management and optoelectronic properties.The Ti3C2TX nanosheets,embedded at perovskite grain boundaries,construct efficient thermal conduction pathways,significantly improving the thermal conductivity and diffusivity of the film.This leads to a notable reduction in the device’s steady-state operating temperature from 42.96 to 39.97 under 100 mW cm−2 illumination,thereby alleviating heat-induced performance degradation.Beyond thermal regulation,Ti3C2TX,with high conductivity and negatively charged surface terminations,also serves as an effective defect passivation agent,reducing trap-assisted recombination,while simultaneously facilitating charge extraction and transport by optimizing interfacial energy alignment.As a result,the Ti3C2TX-modified PSC achieve a champion PCE of 25.13%and exhibit outstanding thermal stability,retaining 80%of the initial PCE after 500 h of thermal aging at 85 and 30±5%relative humidity.(In contrast,control PSC retain only 58%after 200 h.)Moreover,under continuous maximum power point tracking in N2 atmosphere,Ti3C2TX-modified PSC retained 70%of the initial PCE after 500 h,whereas the control PSC drop sharply to 20%.These findings highlight the synergistic role of Ti3C2TX in thermal management and optoelectronic performance,paving the way for the development of high-efficiency and heat-resistant perovskite photovoltaics.展开更多
As a core component in the electrochemical water splitting system,the cathode catalyst is capable of boosting the kinetics of the hydrogen evolution reaction(HER),while the scarcity and expenditure of current noble me...As a core component in the electrochemical water splitting system,the cathode catalyst is capable of boosting the kinetics of the hydrogen evolution reaction(HER),while the scarcity and expenditure of current noble metal-based electrocatalysts seriously restrict the large-scale commercial development of hydrogen manufacturing devices.Here,we present a robust and controllable self-assembly method for the spatial construction of three-dimensional(3D)porous ternary nanoarchitectures comprising Ti3C2Tx MXene,MoS2nanosheets,and graphene(MX/MoS2/G).This bottom-up strategy contributes to the intriguing structural features of the resulting nanoarchitectures,including 3D crosslinked porous networks,ultrathin walls,plentiful exposed reactive sites,and numerous efficient electron channels.As a consequence,the optimized MX/MoS2/G electrocatalyst depicts superior electrocatalytic HER performance in terms of a competitive onset potential,a small Tafel slope,a large electrochemically active surface area,and exceptional durability,which significantly outperforms the bare MXene,MoS2,graphene,as well as binary MXene/graphene and MoS2/graphene electrocatalysts.展开更多
Flexible sensors have emerged as a promising tool in applications ranging from pilot physiological monitoring to motion capture and complex training environments.However,conventional approaches often face inherent lim...Flexible sensors have emerged as a promising tool in applications ranging from pilot physiological monitoring to motion capture and complex training environments.However,conventional approaches often face inherent limitations,such as susceptibility to electromagnetic interference,instability in humid or sweat-rich conditions,and restricted multifunctional integration.To overcome these challenges,we present a flexible sensor based on a multifunctional MXene/LIG composite structure.By combining surface-modified MXene with laser-induced graphene(LIG),we developed a robust conductive framework characterized by hierarchical porosity.Thanks to this innovative design,the sensor achieves exceptional multifunctional performance.It exhibits high electromagnetic shielding effectiveness of 31.5 dB through synergistic reflection and absorption,demonstrates strong hydrophobicity with a contact angle of 151.1°,and delivers enhanced thermal conductivity.These features enable accurate monitoring of operational movements in simulated cockpit environments while ensuring durable performance under complex aviation requirements.Moreover,this design strategy offers a novel pathway for advancing high-performance flexible sensors,opening new opportunities in wearable electronics,healthcare monitoring,and intelligent human-machine interaction systems.展开更多
Mechanical dynamic sealing components are usually subjected to the erosion of a hydrothermal environment;thus,the selected service materials must meet stringent requirements for superior self-lubrication,corrosion res...Mechanical dynamic sealing components are usually subjected to the erosion of a hydrothermal environment;thus,the selected service materials must meet stringent requirements for superior self-lubrication,corrosion resistance,and thermal stability.Herein,we report a rationally engineered MXene@BN heterostructure as the reinforcing phase for the polytetrafluoroethylene(PTFE)coating to stably improve the friction properties in the hydrothermal environment.The two-dimensional heterogeneous structure enhances the hydrothermal stability via the synergistic effect between MXene and h-BN.Specifically,h-BN serves as a robust physical barrier that impedes the penetration of water and oxygen,thereby significantly suppressing the oxidation of MXene.Meanwhile,MXene provides effective load-bearing and lubricating functions,and acts as a framework to construct a two-dimensional network within the PTFE matrix,which substantially improves the structural stability of the coating under a hydrothermal environment.More importantly,MXene@BN plays a crucial role as a“transfer bridge,”facilitating the formation of a stable friction transfer film,thus achieving in situ fixation of the third-body abrasive particles and reducing the secondary damage to the film.Consequently,with the doping of MXene@BN,the surface energy of the composite coating exhibited a 17%increase,whereas the cooling rate demonstrated a modest elevation from 0.31 to 0.33℃ s−1.A stable enhancement of friction and wear performance is achieved under a hydrothermal environment,where the wear rate exhibited a maximum reduction of approximately 48.9%,whereas the friction coefficient decreased from 0.18 to a minimum of 0.05,representing a reduction of approximately 72.2%.This work demonstrates a scalable effective heterostructure engineering strategy,establishing MXene@BN as a promising platform for enhancing the friction properties of PTFE coatings under hydrothermal environments.展开更多
The efficient healing rate for self-healing anticorrosion coatings plays an essential role on resisting rapidly developed corrosion and providing sufficient protection properties.The anticorrosion poly(urethane-urea)(...The efficient healing rate for self-healing anticorrosion coatings plays an essential role on resisting rapidly developed corrosion and providing sufficient protection properties.The anticorrosion poly(urethane-urea)(PU)coatings reinforced by mesoporous polydopamine modified Ti3C2TxMXene(MPDA/Ti3C2Tx)were constructed.MPDA/Ti3C2Txwas embedded to offer hierarchically interfacial interactions through microscopic hydrogen bonding in PU chains-PDA molecules,and mesoscopic engaging effects originated from PU matrix anchoring interface mesopores.Hydrogen and disulfide bonds are co-incorporated into PU for producing room-temperature self-healing ability.What's more,the photothermal conversion capability of MPDA/Ti3C2Txendows PU coating with greatly accelerated self-healing rate to resist corrosion expansion.The healed coating exhibited promising stability in simulated seawater after 47 d,proving the practicality and feasibility in protection application of marine facilities.展开更多
Accurate monitoring of electrophysiological signals through epidermal electrodes is crucial for advancing human–machine interfaces and wearable healthcare. While highly conductive materials are conventionally used as...Accurate monitoring of electrophysiological signals through epidermal electrodes is crucial for advancing human–machine interfaces and wearable healthcare. While highly conductive materials are conventionally used as epidermal electrodes, their limited electrochemical performance results in high interfacial impedance and consequent signal distortion. Here, we present an electrochemically enhanced low-impedance Ti3C2Tx MXene epidermal electrode for accurate electrophysiological monitoring. The low interfacial impedance is achieved by producing and bridging large Ti3C2Tx MXene nanosheets. Large MXene nanosheets were prepared by combining precursor particle sedimentation with mild shear-assisted exfoliation. An orderly stacking structure was constructed through hydroxyethyl cellulose(HEC) crosslinking large MXene nanosheets to enhance electrochemical performance and flexibility. The epidermal electrodes were fabricated by bonding HEC/MXene film to poly(dimethylsiloxane) substrate via in-situ curing. The MXene epidermal electrodes exhibit lower interfacial impedance(53 k Ω cm2 at 10 Hz) compared to standard Ag/AgCl gel electrodes(436 k Ω cm2 at 10 Hz). This reduction results in a 2.4-fold improvement in signal-to-noise ratio, enabling accurate electrophysiological monitoring. A miniature recording system is integrated with the epidermal electrodes to monitor electrophysiological signals in wearable scenes. Physiological applications have been validated in gesture recognition and health monitoring. Therefore, the electrochemically enhanced low-impedance MXene epidermal electrodes offer a reliable option for acquiring high-fidelity electrophysiological signals.展开更多
The rapid advancement of 5G communication technology has intensified electromagnetic pollution,creating an urgent demand for flexible multifunctional fabrics with efficient electromagnetic interference(EMI)shielding p...The rapid advancement of 5G communication technology has intensified electromagnetic pollution,creating an urgent demand for flexible multifunctional fabrics with efficient electromagnetic interference(EMI)shielding performance.This study proposes a novel material-stacked construction strategy to fabricate multifunctional MXene/cellulose nanofiber/polyvinyl butyral(MXene/CNF/PVB)composite fabrics by sequentially depositing two-dimensional MXene nanosheets,CNF,and PVB onto the surface of linen fabric.Benefiting from the pretreatment with the cationic polyelectrolyte poly(diallyldimethylammonium chloride)(PDDA),MXene nanosheets can adhere firmly to the fibers via electrostatic self-assembly and impart the fabric with excellent EMI shielding performance(47.87 dB).Meanwhile,optimizing the CNF concentration effectively enhances the mechanical strength of the fabric(45.27 MPa).The incorporation of PVB significantly improves the environmental stability and durability of the composite fabrics.As a result of the synergistic combination of high electrical conductivity and favorable infrared radiation suppression characteristics of MXene,the fabricated MXene/CNF/PVB composite-coated fabric achieved a mechanical strength of 49.68 MPa,an EMI SE of 39.31 dB,efficient Joule heating(62.5℃at 5 V),and effective infrared stealth,as evidenced by a low radiation temperature of 51.3℃against a 100℃background.These results demonstrate the strong potential of MXene/CNF/PVB composite fabrics for next-generation wearable and multifunctional electronic applications.展开更多
To overcome lithium polysulfide(LiPS)shuttling and lithium dendrite growth in lithium-sulfur(Li-S)batteries,a high-entropy MXene(HE-MXene,(Ti1/5V1/5Nb1/5Mo1/5Cr1/5)3C2)containing five uniformly di...To overcome lithium polysulfide(LiPS)shuttling and lithium dendrite growth in lithium-sulfur(Li-S)batteries,a high-entropy MXene(HE-MXene,(Ti1/5V1/5Nb1/5Mo1/5Cr1/5)3C2)containing five uniformly distributed transition metals in its M layer is fabricated for use as a multifunctional separator modifier.The precisely engineered multimetal active centers in the HE-MXene optimize the d-band electronic structure,establishing a relay catalytic mechanism wherein the metal sites synergistically promote multistep sulfur redox reactions.Consequently,a continuous trapping-catalysis-conversion system that effectively inhibits LiPS migration is established.As a separator coating,the HE-MXene enables uniform lithium deposition due to its excellent ionic conductivity,lattice distortion effects,and the formation of a LiF-rich solid electrolyte interphase.These effects enhance the electrochemical performance of Li-S cells,including exceptional cycling stability with a capacity decay rate of only 0.014%per cycle over 1500 cycles at 2C and excellent rate capability.The Li-S pouch cells with HE-MXene/PP separators exhibit favorable cycling stability.Overall,this study highlights the dual functionality of HE-MXenes in stabilizing sulfur cathodes and lithium anodes while establishing fundamental design principles for advanced electrocatalytic materials in energy storage systems via atomic-level engineering.展开更多
基金the National Natural Science Foundation of China(Nos.62374029,22175029,62474033,and W2433038)the Young Elite Scientists Sponsorship Program by CAST(No.YESS20220550)+2 种基金the Sichuan Science and Technology Program(No.2024NSFSC0250)the Natural Science Foundation of Shenzhen Innovation Committee(JCYJ20210324135614040)the Fundamental Research Funds for the Central Universities of China(No.ZYGX2022J032).
摘要Perovskite solar cells(PSCs)have emerged as promising photovoltaic technologies owing to their remarkable power conversion efficiency(PCE).However,heat accumulation under continuous illumination remains a critical bottleneck,severely affecting device stability and long-term operational performance.Herein,we present a multifunctional strategy by incorporating highly thermally conductive Ti3C2TX MXene nanosheets into the perovskite layer to simultaneously enhance thermal management and optoelectronic properties.The Ti3C2TX nanosheets,embedded at perovskite grain boundaries,construct efficient thermal conduction pathways,significantly improving the thermal conductivity and diffusivity of the film.This leads to a notable reduction in the device’s steady-state operating temperature from 42.96 to 39.97 under 100 mW cm−2 illumination,thereby alleviating heat-induced performance degradation.Beyond thermal regulation,Ti3C2TX,with high conductivity and negatively charged surface terminations,also serves as an effective defect passivation agent,reducing trap-assisted recombination,while simultaneously facilitating charge extraction and transport by optimizing interfacial energy alignment.As a result,the Ti3C2TX-modified PSC achieve a champion PCE of 25.13%and exhibit outstanding thermal stability,retaining 80%of the initial PCE after 500 h of thermal aging at 85 and 30±5%relative humidity.(In contrast,control PSC retain only 58%after 200 h.)Moreover,under continuous maximum power point tracking in N2 atmosphere,Ti3C2TX-modified PSC retained 70%of the initial PCE after 500 h,whereas the control PSC drop sharply to 20%.These findings highlight the synergistic role of Ti3C2TX in thermal management and optoelectronic performance,paving the way for the development of high-efficiency and heat-resistant perovskite photovoltaics.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.22209037 and 52472092)。
摘要As a core component in the electrochemical water splitting system,the cathode catalyst is capable of boosting the kinetics of the hydrogen evolution reaction(HER),while the scarcity and expenditure of current noble metal-based electrocatalysts seriously restrict the large-scale commercial development of hydrogen manufacturing devices.Here,we present a robust and controllable self-assembly method for the spatial construction of three-dimensional(3D)porous ternary nanoarchitectures comprising Ti3C2Tx MXene,MoS2nanosheets,and graphene(MX/MoS2/G).This bottom-up strategy contributes to the intriguing structural features of the resulting nanoarchitectures,including 3D crosslinked porous networks,ultrathin walls,plentiful exposed reactive sites,and numerous efficient electron channels.As a consequence,the optimized MX/MoS2/G electrocatalyst depicts superior electrocatalytic HER performance in terms of a competitive onset potential,a small Tafel slope,a large electrochemically active surface area,and exceptional durability,which significantly outperforms the bare MXene,MoS2,graphene,as well as binary MXene/graphene and MoS2/graphene electrocatalysts.
基金Project supported from Research Fund on Sichuan Civil Aviation Flight Technology and Flight Safety Engineering Technology(Grant Nos.GY2024-10C and GY2025-16C)the Basic Scientific Research Expenses of Central Universities(Grant Nos.24CAFUC03020 and 24CAFUC03022)+1 种基金the Graduate Research Innovation Fund of Civil Aviation Flight University of China(Grant No.25CAFUC10018)the Open Fund of Key Laboratory of Flight Techniques and Flight Safety,CAAC(Grant No.F2024KF24E)。
摘要Flexible sensors have emerged as a promising tool in applications ranging from pilot physiological monitoring to motion capture and complex training environments.However,conventional approaches often face inherent limitations,such as susceptibility to electromagnetic interference,instability in humid or sweat-rich conditions,and restricted multifunctional integration.To overcome these challenges,we present a flexible sensor based on a multifunctional MXene/LIG composite structure.By combining surface-modified MXene with laser-induced graphene(LIG),we developed a robust conductive framework characterized by hierarchical porosity.Thanks to this innovative design,the sensor achieves exceptional multifunctional performance.It exhibits high electromagnetic shielding effectiveness of 31.5 dB through synergistic reflection and absorption,demonstrates strong hydrophobicity with a contact angle of 151.1°,and delivers enhanced thermal conductivity.These features enable accurate monitoring of operational movements in simulated cockpit environments while ensuring durable performance under complex aviation requirements.Moreover,this design strategy offers a novel pathway for advancing high-performance flexible sensors,opening new opportunities in wearable electronics,healthcare monitoring,and intelligent human-machine interaction systems.
基金supported by Gansu Provincial Talent Programs(Grant No.2024CXPT-02)the Key Research and Development Program of Gansu Province(Grant No.25YFGA011)+1 种基金the Research and Innovation Office of The Hong Kong Polytechnic University(Project codes:4-W413)the National Natural Science Foundation of China(Grant Nos.52505229 and 52061027).
摘要Mechanical dynamic sealing components are usually subjected to the erosion of a hydrothermal environment;thus,the selected service materials must meet stringent requirements for superior self-lubrication,corrosion resistance,and thermal stability.Herein,we report a rationally engineered MXene@BN heterostructure as the reinforcing phase for the polytetrafluoroethylene(PTFE)coating to stably improve the friction properties in the hydrothermal environment.The two-dimensional heterogeneous structure enhances the hydrothermal stability via the synergistic effect between MXene and h-BN.Specifically,h-BN serves as a robust physical barrier that impedes the penetration of water and oxygen,thereby significantly suppressing the oxidation of MXene.Meanwhile,MXene provides effective load-bearing and lubricating functions,and acts as a framework to construct a two-dimensional network within the PTFE matrix,which substantially improves the structural stability of the coating under a hydrothermal environment.More importantly,MXene@BN plays a crucial role as a“transfer bridge,”facilitating the formation of a stable friction transfer film,thus achieving in situ fixation of the third-body abrasive particles and reducing the secondary damage to the film.Consequently,with the doping of MXene@BN,the surface energy of the composite coating exhibited a 17%increase,whereas the cooling rate demonstrated a modest elevation from 0.31 to 0.33℃ s−1.A stable enhancement of friction and wear performance is achieved under a hydrothermal environment,where the wear rate exhibited a maximum reduction of approximately 48.9%,whereas the friction coefficient decreased from 0.18 to a minimum of 0.05,representing a reduction of approximately 72.2%.This work demonstrates a scalable effective heterostructure engineering strategy,establishing MXene@BN as a promising platform for enhancing the friction properties of PTFE coatings under hydrothermal environments.
基金financially supported by the National Natural Science Foundation of China(Nos.52401096,52201077,and 52403096)the Natural Science Foundation of Shandong Province(Nos.ZR2024QE462 and ZR2022QE191)+3 种基金project 24-4-4-zrjj-54-jch supported by Qingdao Natural Science FoundationResearch Start-up Fund of Qingdao University of Science and Technology(No.12030430010982)the Taishan Scholars Program(No.tsqn202312206)Youth Innovation Team of Shandong Province Higher Education Institutions(No.2023KJ308)。
摘要The efficient healing rate for self-healing anticorrosion coatings plays an essential role on resisting rapidly developed corrosion and providing sufficient protection properties.The anticorrosion poly(urethane-urea)(PU)coatings reinforced by mesoporous polydopamine modified Ti3C2TxMXene(MPDA/Ti3C2Tx)were constructed.MPDA/Ti3C2Txwas embedded to offer hierarchically interfacial interactions through microscopic hydrogen bonding in PU chains-PDA molecules,and mesoscopic engaging effects originated from PU matrix anchoring interface mesopores.Hydrogen and disulfide bonds are co-incorporated into PU for producing room-temperature self-healing ability.What's more,the photothermal conversion capability of MPDA/Ti3C2Txendows PU coating with greatly accelerated self-healing rate to resist corrosion expansion.The healed coating exhibited promising stability in simulated seawater after 47 d,proving the practicality and feasibility in protection application of marine facilities.
基金financial support from the National Natural Science Foundation of China (No. 52232006, U25A20236, 52188101, 52372133, 52472145 and 52502162)。
摘要Accurate monitoring of electrophysiological signals through epidermal electrodes is crucial for advancing human–machine interfaces and wearable healthcare. While highly conductive materials are conventionally used as epidermal electrodes, their limited electrochemical performance results in high interfacial impedance and consequent signal distortion. Here, we present an electrochemically enhanced low-impedance Ti3C2Tx MXene epidermal electrode for accurate electrophysiological monitoring. The low interfacial impedance is achieved by producing and bridging large Ti3C2Tx MXene nanosheets. Large MXene nanosheets were prepared by combining precursor particle sedimentation with mild shear-assisted exfoliation. An orderly stacking structure was constructed through hydroxyethyl cellulose(HEC) crosslinking large MXene nanosheets to enhance electrochemical performance and flexibility. The epidermal electrodes were fabricated by bonding HEC/MXene film to poly(dimethylsiloxane) substrate via in-situ curing. The MXene epidermal electrodes exhibit lower interfacial impedance(53 k Ω cm2 at 10 Hz) compared to standard Ag/AgCl gel electrodes(436 k Ω cm2 at 10 Hz). This reduction results in a 2.4-fold improvement in signal-to-noise ratio, enabling accurate electrophysiological monitoring. A miniature recording system is integrated with the epidermal electrodes to monitor electrophysiological signals in wearable scenes. Physiological applications have been validated in gesture recognition and health monitoring. Therefore, the electrochemically enhanced low-impedance MXene epidermal electrodes offer a reliable option for acquiring high-fidelity electrophysiological signals.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.52173236 and 62371103)the Natural Science Foundation of Sichuan Province(Grant No.2023NSFSC0410)。
摘要The rapid advancement of 5G communication technology has intensified electromagnetic pollution,creating an urgent demand for flexible multifunctional fabrics with efficient electromagnetic interference(EMI)shielding performance.This study proposes a novel material-stacked construction strategy to fabricate multifunctional MXene/cellulose nanofiber/polyvinyl butyral(MXene/CNF/PVB)composite fabrics by sequentially depositing two-dimensional MXene nanosheets,CNF,and PVB onto the surface of linen fabric.Benefiting from the pretreatment with the cationic polyelectrolyte poly(diallyldimethylammonium chloride)(PDDA),MXene nanosheets can adhere firmly to the fibers via electrostatic self-assembly and impart the fabric with excellent EMI shielding performance(47.87 dB).Meanwhile,optimizing the CNF concentration effectively enhances the mechanical strength of the fabric(45.27 MPa).The incorporation of PVB significantly improves the environmental stability and durability of the composite fabrics.As a result of the synergistic combination of high electrical conductivity and favorable infrared radiation suppression characteristics of MXene,the fabricated MXene/CNF/PVB composite-coated fabric achieved a mechanical strength of 49.68 MPa,an EMI SE of 39.31 dB,efficient Joule heating(62.5℃at 5 V),and effective infrared stealth,as evidenced by a low radiation temperature of 51.3℃against a 100℃background.These results demonstrate the strong potential of MXene/CNF/PVB composite fabrics for next-generation wearable and multifunctional electronic applications.
基金partially supported by the National Natural Science Foundation of China(22409044)the Natural Science Foundation of Heilongjiang Province,China(LH2023E079)。
摘要To overcome lithium polysulfide(LiPS)shuttling and lithium dendrite growth in lithium-sulfur(Li-S)batteries,a high-entropy MXene(HE-MXene,(Ti1/5V1/5Nb1/5Mo1/5Cr1/5)3C2)containing five uniformly distributed transition metals in its M layer is fabricated for use as a multifunctional separator modifier.The precisely engineered multimetal active centers in the HE-MXene optimize the d-band electronic structure,establishing a relay catalytic mechanism wherein the metal sites synergistically promote multistep sulfur redox reactions.Consequently,a continuous trapping-catalysis-conversion system that effectively inhibits LiPS migration is established.As a separator coating,the HE-MXene enables uniform lithium deposition due to its excellent ionic conductivity,lattice distortion effects,and the formation of a LiF-rich solid electrolyte interphase.These effects enhance the electrochemical performance of Li-S cells,including exceptional cycling stability with a capacity decay rate of only 0.014%per cycle over 1500 cycles at 2C and excellent rate capability.The Li-S pouch cells with HE-MXene/PP separators exhibit favorable cycling stability.Overall,this study highlights the dual functionality of HE-MXenes in stabilizing sulfur cathodes and lithium anodes while establishing fundamental design principles for advanced electrocatalytic materials in energy storage systems via atomic-level engineering.