Two-dimension(2D)van der Waals heterojunction holds essential promise in achieving high-performance flexible near-infrared(NIR)photodetector.Here,we report the successful fabrication of ZnSb/Ti_(3)C_(2)T_(x)MXene base...Two-dimension(2D)van der Waals heterojunction holds essential promise in achieving high-performance flexible near-infrared(NIR)photodetector.Here,we report the successful fabrication of ZnSb/Ti_(3)C_(2)T_(x)MXene based flexible NIR photodetector array via a facile photolithography technology.The single ZnSb/Ti_(3)C_(2)T_(x)photodetector exhibited a high light-to-dark current ratio of 4.98,fast response/recovery time(2.5/1.3 s)and excellent stability due to the tight connection between 2D ZnSb nanoplates and 2D Ti_(3)C_(2)T_(x)MXene nanoflakes,and the formed 2D van der Waals heterojunction.Thin polyethylene terephthalate(PET)substrate enables the ZnSb/Ti_(3)C_(2)T_(x)photodetector withstand bending such that stable photoelectrical properties with non-obvious change were maintained over 5000 bending cycles.Moreover,the ZnSb/Ti_(3)C_(2)T_(x)photodetectors were integrated into a 26×5 device array,realizing a NIR image sensing application.展开更多
Potassium-ion batteries(PIBs)offer a cost-effective and resource-abundant solution for large-scale energy storage.However,the progress of PIBs is impeded by the lack of high-capacity,long-life,and fast-kinetics anode ...Potassium-ion batteries(PIBs)offer a cost-effective and resource-abundant solution for large-scale energy storage.However,the progress of PIBs is impeded by the lack of high-capacity,long-life,and fast-kinetics anode electrode materials.Here,we propose a dual synergic optimization strategy to enhance the K^(+)storage stability and reaction kinetics of Bi_(2)S_(3) through two-dimensional compositing and cation doping.Externally,Bi_(2)S_(3) nanoparticles are loaded onto the surface of three-dimensional interconnected Ti_(3)C_(2)T_(x) nanosheets to stabilize the electrode structure.Internally,Cu^(2+)doping acts as active sites to accelerate K^(+)storage kinetics.Various theoretical simulations and ex situ techniques are used to elucidate the external–internal dual synergism.During discharge,Ti_(3)C_(2)T_(x) and Cu^(2+)collaboratively facilitate K+intercalation.Subsequently,Cu^(2+)doping primarily promotes the fracture of Bi2S3 bonds,facilitating a conversion reaction.Throughout cycling,the Ti_(3)C_(2)T_(x) composite structure and Cu^(2+)doping sustain functionality.The resulting Cu^(2+)-doped Bi2S3 anchored on Ti_(3)C_(2)T_(x)(C-BT)shows excellent rate capability(600 mAh g^(-1) at 0.1 A g^(–1);105 mAh g^(-1) at 5.0 A g^(-1))and cycling performance(91 mAh g^(-1) at 5.0 A g^(-1) after 1000 cycles)in half cells and a high energy density(179 Wh kg–1)in full cells.展开更多
P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phas...P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phases remains a necessity.Herein,we design a P2/O3-type Na_(0.76)Ni_(0.31)Zn_(0.07)Mn_(0.50)Ti_(0.12)0_(2)(NNZMT)with high chemical/electrochemical stability by enhancing the coupling between the two phases.For the first time,a unique Na*extraction is observed from a Na-rich O3 phase by a Na-poor P2 phase and systematically investigated.This process is facilitated by Zn^(2+)/Ti^(4+)dual doping and calcination condition regulation,allowing a higher Na*content in the P2 phase with larger Na^(+)transport channels and enhancing Na transport kinetics.Because of reduced Na^(+)in the O3 phase,which increases the difficulty of H^(+)/Na^(+) exchange,the hydrostability of the O3 phase in NNZMT is considerably improved.Furthermore,Zn^(2+)/Ti^(4+)presence in NNZMT synergistically regulates oxygen redox chemistry,which effectively suppresses O_(2)/CO_(2) gas release and electrolyte decomposition,and completely inhibits phase transitions above 4.0 V.As a result,NNZMT achieves a high discharge capacity of 144.8 mA h g^(-1) with a median voltage of 3.42 V at 20 mA g^(-1) and exhibits excellent cycling performance with a capacity retention of 77.3% for 1000 cycles at 2000 mA g^(-1).This study provides an effective strategy and new insights into the design of high-performance layered-oxide cathode materials with enhanced structure/interface stability forSIBs.展开更多
Indium oxide(In_(2)O_(3)),as a promising candidate for CO_(2)hydrogenation to C_(1) products,often suffers from sintering and activity decline,closely related to the undesirable structural evolution under reaction con...Indium oxide(In_(2)O_(3)),as a promising candidate for CO_(2)hydrogenation to C_(1) products,often suffers from sintering and activity decline,closely related to the undesirable structural evolution under reaction conditions.Based on the comprehension of the dynamic evolution,this study presents an efficient strategy to alleviate the agglomeration of In_(2)O_(3)nanoparticles by the surface decoration with highly dispersed silica species(SiO_(x)).Various structural characterizations combined with density functional theory calculations demonstrated that the sintering resulted from the over-reduction,while the enhanced stability originated from the anchoring effect of highly stable In-OSi bonds,which hinders the substantial formation of metallic In(In^(0))and the subsequent agglomeration.0.6Si/In_(2)O_(3)exhibited CO_(2)conversion rate of10.0 mmol g^(-1)h^(-1)at steady state vs.3.5 mmol g^(-1)h^(-1)on In_(2)O_(3)in CO_(2)hydrogenation.Enhanced steady-state activity was also achieved on Pd-modified catalysts.Compared to the traditional Pd/In_(2)O_(3)catalyst,the methanol production rate of Pd catalyst supported on 0.6Si/In_(2)O_(3)was enhanced by 23%,showing the potential of In_(2)O_(3)modified by SiO_(x)in serving as a platform material.This work provides a promising method to design new In_(2)O_(3)-based catalysts with improved activity and stability in CO_(2)hydrogenation.展开更多
Developing efficient energy storage for sodium-ion batteries(SIBs)by creating high-performance heterojunctions and understanding their interfacial interaction at the atomic/molecular level holds promise but is also ch...Developing efficient energy storage for sodium-ion batteries(SIBs)by creating high-performance heterojunctions and understanding their interfacial interaction at the atomic/molecular level holds promise but is also challenging.Besides,sluggish reaction kinetics at low temperatures restrict the operation of SIBs in cold climates.Herein,cross-linking nanoarchitectonics of WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,featuring built-in electric field(BIEF),have been developed,employing as a model to reveal the positive effect of heterojunction design and BIEF for modifying the reaction kinetics and electrochemical activity.Particularly,the theoretical analysis manifests the discrepancy in work functions leads to the electronic flow from the electron-rich Ti_(3)C_(2)T_(x) to layered WS_(2),spontaneously forming the BIEF and“ion reservoir”at the heterogeneous interface.Besides,the generation of cross-linking pathways further promotes the transportation of electrons/ions,which guarantees rapid diffusion kinetics and excellent structure coupling.Consequently,superior sodium storage performance is obtained for the WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,with only 0.2%decay per cycle at 5.0 A g^(-1)(25℃)up to 1000 cycles and a high capacity of 293.5 mA h g^(-1)(0.1A g^(-1)after 100 cycles)even at-20℃.Importantly,the spontaneously formed BIEF,accompanied by“ion reservoir”,in heterojunction provides deep understandings of the correlation between structure fabricated and performance obtained.展开更多
Thermally chargeable supercapacitors can collect low-grade heat generated by the human body and convert it into electricity as a power supply unit for wearable electronics.However,the low Seebeck coefficient and heat-...Thermally chargeable supercapacitors can collect low-grade heat generated by the human body and convert it into electricity as a power supply unit for wearable electronics.However,the low Seebeck coefficient and heat-to-electricity conversion efficiency hinder further application.In this paper,we designed a high-performance thermally chargeable supercapacitor device composed of ZnMn_(2)O_(4)@Ti_(3)C_(2)T_(x)MXene composites(ZMO@Ti_(3)C_(2)T_(x)MXene)electrode and UIO-66 metal–organic framework doped multichannel polyvinylidene fluoridehexafluoro-propylene ionogel electrolyte,which realized the thermoelectric conversion and electrical energy storage at the same time.This thermally chargeable supercapacitor device exhibited a high Seebeck coefficient of 55.4 mV K^(−1),thermal voltage of 243 mV,and outstanding heat-to-electricity conversion efficiency of up to 6.48%at the temperature difference of 4.4 K.In addition,this device showed excellent charge–discharge cycling stability at high-temperature differences(3 K)and low-temperature differences(1 K),respectively.Connecting two thermally chargeable supercapacitor units in series,the generated output voltage of 500 mV further confirmed the stability of devices.When a single device was worn on the arm,a thermal voltage of 208.3 mV was obtained indicating the possibility of application in wearable electronics.展开更多
基金supported by National Natural Science Foundation of China(51672308,51972025,61888102,and 62004187).
文摘Two-dimension(2D)van der Waals heterojunction holds essential promise in achieving high-performance flexible near-infrared(NIR)photodetector.Here,we report the successful fabrication of ZnSb/Ti_(3)C_(2)T_(x)MXene based flexible NIR photodetector array via a facile photolithography technology.The single ZnSb/Ti_(3)C_(2)T_(x)photodetector exhibited a high light-to-dark current ratio of 4.98,fast response/recovery time(2.5/1.3 s)and excellent stability due to the tight connection between 2D ZnSb nanoplates and 2D Ti_(3)C_(2)T_(x)MXene nanoflakes,and the formed 2D van der Waals heterojunction.Thin polyethylene terephthalate(PET)substrate enables the ZnSb/Ti_(3)C_(2)T_(x)photodetector withstand bending such that stable photoelectrical properties with non-obvious change were maintained over 5000 bending cycles.Moreover,the ZnSb/Ti_(3)C_(2)T_(x)photodetectors were integrated into a 26×5 device array,realizing a NIR image sensing application.
基金This work received financial support from the National Natural Science Foundation of China(Grant Nos.U23A20574,52250010,and 52201242)the 261 Project MIIT,the Young Elite Scientists Sponsorship Program by CAST(Grant No.2021QNRC001)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.2242022R40018)the Jiangsu Funding Program for Excellent Postdoctoral Talent(Grant No.2022ZB75).
文摘Potassium-ion batteries(PIBs)offer a cost-effective and resource-abundant solution for large-scale energy storage.However,the progress of PIBs is impeded by the lack of high-capacity,long-life,and fast-kinetics anode electrode materials.Here,we propose a dual synergic optimization strategy to enhance the K^(+)storage stability and reaction kinetics of Bi_(2)S_(3) through two-dimensional compositing and cation doping.Externally,Bi_(2)S_(3) nanoparticles are loaded onto the surface of three-dimensional interconnected Ti_(3)C_(2)T_(x) nanosheets to stabilize the electrode structure.Internally,Cu^(2+)doping acts as active sites to accelerate K^(+)storage kinetics.Various theoretical simulations and ex situ techniques are used to elucidate the external–internal dual synergism.During discharge,Ti_(3)C_(2)T_(x) and Cu^(2+)collaboratively facilitate K+intercalation.Subsequently,Cu^(2+)doping primarily promotes the fracture of Bi2S3 bonds,facilitating a conversion reaction.Throughout cycling,the Ti_(3)C_(2)T_(x) composite structure and Cu^(2+)doping sustain functionality.The resulting Cu^(2+)-doped Bi2S3 anchored on Ti_(3)C_(2)T_(x)(C-BT)shows excellent rate capability(600 mAh g^(-1) at 0.1 A g^(–1);105 mAh g^(-1) at 5.0 A g^(-1))and cycling performance(91 mAh g^(-1) at 5.0 A g^(-1) after 1000 cycles)in half cells and a high energy density(179 Wh kg–1)in full cells.
基金supported by the National Natural Science Foundation of China (22169002)the Chongzuo Key Research and Development Program of China (20220603)the Counterpart Aid Project for Discipline Construction from Guangxi University(2023M02)
文摘P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phases remains a necessity.Herein,we design a P2/O3-type Na_(0.76)Ni_(0.31)Zn_(0.07)Mn_(0.50)Ti_(0.12)0_(2)(NNZMT)with high chemical/electrochemical stability by enhancing the coupling between the two phases.For the first time,a unique Na*extraction is observed from a Na-rich O3 phase by a Na-poor P2 phase and systematically investigated.This process is facilitated by Zn^(2+)/Ti^(4+)dual doping and calcination condition regulation,allowing a higher Na*content in the P2 phase with larger Na^(+)transport channels and enhancing Na transport kinetics.Because of reduced Na^(+)in the O3 phase,which increases the difficulty of H^(+)/Na^(+) exchange,the hydrostability of the O3 phase in NNZMT is considerably improved.Furthermore,Zn^(2+)/Ti^(4+)presence in NNZMT synergistically regulates oxygen redox chemistry,which effectively suppresses O_(2)/CO_(2) gas release and electrolyte decomposition,and completely inhibits phase transitions above 4.0 V.As a result,NNZMT achieves a high discharge capacity of 144.8 mA h g^(-1) with a median voltage of 3.42 V at 20 mA g^(-1) and exhibits excellent cycling performance with a capacity retention of 77.3% for 1000 cycles at 2000 mA g^(-1).This study provides an effective strategy and new insights into the design of high-performance layered-oxide cathode materials with enhanced structure/interface stability forSIBs.
基金financially supported by the National Natural Science Foundation of China(22172013)the Special Project for Key Research and Development Program of Xinjiang Autonomous Region(2022B01033-3)+3 种基金the Liaoning Revitalization Talent Program(XLYC2008032 and XLYC2203126)the Fundamental Research Funds for the Central Universities(DUT22LK24,DUT22QN207 and DUT22LAB602)the CUHK Research Startup Fund(No.#4930981)financial support from Catalyst:Seeding funding(CSG-VUW2201)provided by the New Zealand Ministry of Business,Innovation and Employment and administered by the Royal Society Aparangi。
文摘Indium oxide(In_(2)O_(3)),as a promising candidate for CO_(2)hydrogenation to C_(1) products,often suffers from sintering and activity decline,closely related to the undesirable structural evolution under reaction conditions.Based on the comprehension of the dynamic evolution,this study presents an efficient strategy to alleviate the agglomeration of In_(2)O_(3)nanoparticles by the surface decoration with highly dispersed silica species(SiO_(x)).Various structural characterizations combined with density functional theory calculations demonstrated that the sintering resulted from the over-reduction,while the enhanced stability originated from the anchoring effect of highly stable In-OSi bonds,which hinders the substantial formation of metallic In(In^(0))and the subsequent agglomeration.0.6Si/In_(2)O_(3)exhibited CO_(2)conversion rate of10.0 mmol g^(-1)h^(-1)at steady state vs.3.5 mmol g^(-1)h^(-1)on In_(2)O_(3)in CO_(2)hydrogenation.Enhanced steady-state activity was also achieved on Pd-modified catalysts.Compared to the traditional Pd/In_(2)O_(3)catalyst,the methanol production rate of Pd catalyst supported on 0.6Si/In_(2)O_(3)was enhanced by 23%,showing the potential of In_(2)O_(3)modified by SiO_(x)in serving as a platform material.This work provides a promising method to design new In_(2)O_(3)-based catalysts with improved activity and stability in CO_(2)hydrogenation.
基金supported by the faculty startup funds from the Yangzhou Universitythe Natural Science Foundation of Jiangsu Province(BK20210821)+1 种基金the National Natural Science Foundation of China(22102141)the Lvyangjinfeng Talent Program of Yangzhou。
文摘Developing efficient energy storage for sodium-ion batteries(SIBs)by creating high-performance heterojunctions and understanding their interfacial interaction at the atomic/molecular level holds promise but is also challenging.Besides,sluggish reaction kinetics at low temperatures restrict the operation of SIBs in cold climates.Herein,cross-linking nanoarchitectonics of WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,featuring built-in electric field(BIEF),have been developed,employing as a model to reveal the positive effect of heterojunction design and BIEF for modifying the reaction kinetics and electrochemical activity.Particularly,the theoretical analysis manifests the discrepancy in work functions leads to the electronic flow from the electron-rich Ti_(3)C_(2)T_(x) to layered WS_(2),spontaneously forming the BIEF and“ion reservoir”at the heterogeneous interface.Besides,the generation of cross-linking pathways further promotes the transportation of electrons/ions,which guarantees rapid diffusion kinetics and excellent structure coupling.Consequently,superior sodium storage performance is obtained for the WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,with only 0.2%decay per cycle at 5.0 A g^(-1)(25℃)up to 1000 cycles and a high capacity of 293.5 mA h g^(-1)(0.1A g^(-1)after 100 cycles)even at-20℃.Importantly,the spontaneously formed BIEF,accompanied by“ion reservoir”,in heterojunction provides deep understandings of the correlation between structure fabricated and performance obtained.
基金supported by the National Natural Science Foundation of China(52273256)Beijing Municipal Natural Science Foundation(L223006)Beijing Institute of Technology Research Found Program for Young Scholars.
文摘Thermally chargeable supercapacitors can collect low-grade heat generated by the human body and convert it into electricity as a power supply unit for wearable electronics.However,the low Seebeck coefficient and heat-to-electricity conversion efficiency hinder further application.In this paper,we designed a high-performance thermally chargeable supercapacitor device composed of ZnMn_(2)O_(4)@Ti_(3)C_(2)T_(x)MXene composites(ZMO@Ti_(3)C_(2)T_(x)MXene)electrode and UIO-66 metal–organic framework doped multichannel polyvinylidene fluoridehexafluoro-propylene ionogel electrolyte,which realized the thermoelectric conversion and electrical energy storage at the same time.This thermally chargeable supercapacitor device exhibited a high Seebeck coefficient of 55.4 mV K^(−1),thermal voltage of 243 mV,and outstanding heat-to-electricity conversion efficiency of up to 6.48%at the temperature difference of 4.4 K.In addition,this device showed excellent charge–discharge cycling stability at high-temperature differences(3 K)and low-temperature differences(1 K),respectively.Connecting two thermally chargeable supercapacitor units in series,the generated output voltage of 500 mV further confirmed the stability of devices.When a single device was worn on the arm,a thermal voltage of 208.3 mV was obtained indicating the possibility of application in wearable electronics.
