Two novel decyloxyphenylquinoxaline-based donor-acceptor （D-A） electroactive monomers bearing dialkoxythiophene as the donor unit are synthesized using Stille coupling reaction. The corresponding polymers, poly[2,3-...Two novel decyloxyphenylquinoxaline-based donor-acceptor （D-A） electroactive monomers bearing dialkoxythiophene as the donor unit are synthesized using Stille coupling reaction. The corresponding polymers, poly[2,3- bis（4-decyloxyphenyl）-5,8-bis（3,4-dimethoxylthiophen-2-yl）quinoxaline] （P1） and poly[2,3-bis（4-decyloxyphenyl）-5,8- bis（2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl）quinoxaline] （P2）, are directly deposited onto the working electrode surface by electropolymerization. All materials were characterized by nuclear magnetic resonance （NMR）, mass spectrometry （MS）, scanning electron microscopy （SEM）, cyclic voltammetry （CV）, ultraviolet-visible absorption spectrometry （UV-Vis） and spectro-electrochemical measurements. Electrochemical studies demonstrate that both polymers are capable of showing both reasonable n- and p-doping processes, and advanced long-term switching stabilities. 3,4-Ethylenedioxythiophene substituted for 3,4-dimethoxythiophene as a donor unit, which enhances the conjugated double-bond character of the conducting polymer, thus leading to a lower electronic band-gap. Likewise, the neutral state color of the synthesized polymer tuned from blue to blue-green corresponding to the red shift of the maximum absorption wavelengths in the visible region. In addition, kinetics study of P1 revealed 42% （595 nm）, 30% （839 nm） and 69% （1500 nm） transmittance changes （A7%）, while P2 exhibited 32% （740 nm）, 71% （2000 nm） at the dominant wavelengths. It was also observed that both films could switch quickly between the neutral state and oxidation state, with the response time less than 1 s both in visible and near infrared regions.展开更多
Two-dimensional(2D)materials have recently provided a new perspective on optoelectronics because of their unique layered structure and excellent physical properties.However,their potential use as optoelectric devices ...Two-dimensional(2D)materials have recently provided a new perspective on optoelectronics because of their unique layered structure and excellent physical properties.However,their potential use as optoelectric devices has been limited by the trade-off between photoresponsivity and response time.Here,based on a vertically stacked atomically thin p-n junction,we propose a gap-mode plasmon structure that simultaneously enables enhanced responsivity and rapid photodetection.The atomically thin 2D materials act as a spacer for enhancing the gap-mode plasmons,and their short transit length in the vertical direction allows fast photocarrier transport.We demonstrate a high responsivity of up to 8.67 A/W with a high operation speed that exceeds 35 MHz under a 30 nW laser power.Spectral photocurrent,absorption,and a numerical simulation are used to verify the effectiveness of the gap-mode plasmons in the device.We believe that the design strategy proposed in this study can pave the way for a platform to overcome the trade-off between responsivity and response time.展开更多
The wide-bandgap semiconductor material Ga_(2)O_(3) exhibits great potential in solar-blind deep-ultraviolet(DUV)photodetection applications,including none-line-of-sight secure optical communication,fire warning,high-...The wide-bandgap semiconductor material Ga_(2)O_(3) exhibits great potential in solar-blind deep-ultraviolet(DUV)photodetection applications,including none-line-of-sight secure optical communication,fire warning,high-voltage electricity monitoring,and maritime fog dispersion navigation.However,Ga_(2)O_(3) photodetectors have traditionally faced challenges in achieving both high responsivity and fast response time,limiting their practical application.Herein,the Ga_(2)O_(3) solar-blind DUV photodetectors with a suspended structure have been constructed for the first time.The photodetector exhibits a high responsivity of 1.51×10^(10) A/W,a sensitive detectivity of 6.01×10^(17) Jones,a large external quantum efficiency of 7.53×10^(12)%,and a fast rise time of 180 ms under 250-nm illumination.Notably,the photodetector achieves both high responsivity and fast response time simultaneously under ultra-weak power intensity excitation of 0.01μW/cm^(2).This important improvement is attributed to the reduction of interface defects,improved carrier transport,efficient carrier separation,and enhanced light absorption enabled by the suspended structure.This work provides valuable insights for designing and optimizing high-performance Ga_(2)O_(3) solar-blind photodetectors.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.51473074 and 31400044)the General and Special Program of the Postdoctoral Science Foundation China(Nos.2013M530397 and 2014T70861)+1 种基金the Postgraduate Innovation Project of China University of Petroleum(East China)(No.YCX2015022)the Fundamental Research Funds for the Central Universities(No.15CX06049A)
文摘Two novel decyloxyphenylquinoxaline-based donor-acceptor （D-A） electroactive monomers bearing dialkoxythiophene as the donor unit are synthesized using Stille coupling reaction. The corresponding polymers, poly[2,3- bis（4-decyloxyphenyl）-5,8-bis（3,4-dimethoxylthiophen-2-yl）quinoxaline] （P1） and poly[2,3-bis（4-decyloxyphenyl）-5,8- bis（2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl）quinoxaline] （P2）, are directly deposited onto the working electrode surface by electropolymerization. All materials were characterized by nuclear magnetic resonance （NMR）, mass spectrometry （MS）, scanning electron microscopy （SEM）, cyclic voltammetry （CV）, ultraviolet-visible absorption spectrometry （UV-Vis） and spectro-electrochemical measurements. Electrochemical studies demonstrate that both polymers are capable of showing both reasonable n- and p-doping processes, and advanced long-term switching stabilities. 3,4-Ethylenedioxythiophene substituted for 3,4-dimethoxythiophene as a donor unit, which enhances the conjugated double-bond character of the conducting polymer, thus leading to a lower electronic band-gap. Likewise, the neutral state color of the synthesized polymer tuned from blue to blue-green corresponding to the red shift of the maximum absorption wavelengths in the visible region. In addition, kinetics study of P1 revealed 42% （595 nm）, 30% （839 nm） and 69% （1500 nm） transmittance changes （A7%）, while P2 exhibited 32% （740 nm）, 71% （2000 nm） at the dominant wavelengths. It was also observed that both films could switch quickly between the neutral state and oxidation state, with the response time less than 1 s both in visible and near infrared regions.
基金This work was supported by the National Research Foundation of Korea(NRF)through Basic Research Program(No.2019R1A2C2009171)Creative Materials Discovery Program(No.2016M3D1A1900035).
文摘Two-dimensional(2D)materials have recently provided a new perspective on optoelectronics because of their unique layered structure and excellent physical properties.However,their potential use as optoelectric devices has been limited by the trade-off between photoresponsivity and response time.Here,based on a vertically stacked atomically thin p-n junction,we propose a gap-mode plasmon structure that simultaneously enables enhanced responsivity and rapid photodetection.The atomically thin 2D materials act as a spacer for enhancing the gap-mode plasmons,and their short transit length in the vertical direction allows fast photocarrier transport.We demonstrate a high responsivity of up to 8.67 A/W with a high operation speed that exceeds 35 MHz under a 30 nW laser power.Spectral photocurrent,absorption,and a numerical simulation are used to verify the effectiveness of the gap-mode plasmons in the device.We believe that the design strategy proposed in this study can pave the way for a platform to overcome the trade-off between responsivity and response time.
基金support from the China Postdoctoral Science Foundation(2023M742732)the Postdoctoral Fellowship Program of CPSF under grant number GZC20241303+3 种基金the Fundamental Research Funds for the Central Universities(XJSJ24100)the National Key R&D Program of China(2023YFB4402303)the National Natural Science Foundation of China(grant nos.62404176,62025402,62090033,92364204,9226420,and 62293522)Major Program of Zhejiang Natural Science Foundation(grant no.LDT23F04024F04).
文摘The wide-bandgap semiconductor material Ga_(2)O_(3) exhibits great potential in solar-blind deep-ultraviolet(DUV)photodetection applications,including none-line-of-sight secure optical communication,fire warning,high-voltage electricity monitoring,and maritime fog dispersion navigation.However,Ga_(2)O_(3) photodetectors have traditionally faced challenges in achieving both high responsivity and fast response time,limiting their practical application.Herein,the Ga_(2)O_(3) solar-blind DUV photodetectors with a suspended structure have been constructed for the first time.The photodetector exhibits a high responsivity of 1.51×10^(10) A/W,a sensitive detectivity of 6.01×10^(17) Jones,a large external quantum efficiency of 7.53×10^(12)%,and a fast rise time of 180 ms under 250-nm illumination.Notably,the photodetector achieves both high responsivity and fast response time simultaneously under ultra-weak power intensity excitation of 0.01μW/cm^(2).This important improvement is attributed to the reduction of interface defects,improved carrier transport,efficient carrier separation,and enhanced light absorption enabled by the suspended structure.This work provides valuable insights for designing and optimizing high-performance Ga_(2)O_(3) solar-blind photodetectors.
