Carbon dots(CDs), a new building unit, have been revolutionizing the fields of biomedicine, bioimaging, and optoelectronics with their excellent physical, chemical, and biological properties. However, the difficulty o...Carbon dots(CDs), a new building unit, have been revolutionizing the fields of biomedicine, bioimaging, and optoelectronics with their excellent physical, chemical, and biological properties. However, the difficulty of preparing excitation-dependent full-spectrum fluorescent CDs has seriously hindered their further research in fluorescence emission mechanisms and biomedicine. Here, we report full-spectrum fluorescent CDs that exhibit controlled emission changes from purple(380 nm) to red(613 nm) at room temperature by changing the excitation wavelength, and the excitation dependence was closely related to the regulation of sp2 and sp3 hybrid carbon structures by β-cyclodextrin-related groups. In addition,by regulating the content of β-cyclodextrin, the optimal quantum yields of full-spectrum fluorescent CDs were 8.97%, 8.35%, 7.90%, 9.69% and 17.4% at the excitation wavelengths of 340, 350, 390, 410 and 540 nm,respectively. Due to their excellent biocompatibility and color tunability, full-spectrum fluorescent CDs emitted bright and steady purple, blue, green, yellow, and red fluorescence in MCF-7 cells. Moreover, we optimized the imaging conditions of CDs and mitochondrial-specific dyes;and realized the mitochondrialtargeted co-localization imaging of purple, blue and green fluorescence. After that, we also explored the effect of full-spectrum fluorescent CDs in vivo fluorescence imaging through the intratumorally, subcutaneously, and caudal vein, and found that full-spectrum fluorescent CDs had good fluorescence imaging ability in vivo.展开更多
High-quality and real-time holographic imaging based on dynamically tunable metasurfaces has attracted immense interest.Despite remarkable progress,the complex electrical pattern designs and slowspeed near-field scann...High-quality and real-time holographic imaging based on dynamically tunable metasurfaces has attracted immense interest.Despite remarkable progress,the complex electrical pattern designs and slowspeed near-field scanning terahertz(THz)microscopy systems have significantly hindered the development of real-time electrically tunable metasurface holography in the THz band.We propose and experimentally demonstrate an electrically tunable vanadium dioxide(VO_(2))-based active metasurface that can generate realtime bias-controlled holographic information via a THz focal plane imaging system.By elaborately designing“microladders”integrated with VO_(2)pads,the device exhibits low power consumption(∼0.8 W)and real-time imaging(∼4.5 s).The quantitative method is theoretically utilized to investigate the thermal parameters dependent thermodynamics of the“ladder”metasurface based on theoretical analysis with the aid of thermal modelling.The calculated dynamic response time based on the quantitative thermodynamic model agrees well with experimental results.Our study can be used to propel the development of THz electrically tunable metasurfaces for low-power-consumption dynamic,real-time displays,and information encryption,providing crucial insights for future optimization of VO_(2)-based electrothermally tunable holographic metasurfaces.展开更多
Two-dimensional noble transition metal chalcogenide(NTMC)semiconductors represent compelling building blocks for fabricating flexible electronic and optoelectronic devices.While binary and ternary compounds have been ...Two-dimensional noble transition metal chalcogenide(NTMC)semiconductors represent compelling building blocks for fabricating flexible electronic and optoelectronic devices.While binary and ternary compounds have been reported,the existence of quaternary NTMCs with a greater elemental degree of freedom remains largely unexplored.This study presents the pioneering experimental realization of a novel semiconducting quaternary NTMC material,AuPdNaS_(2),synthesized directly on Au foils through chemical vapor deposition.The ribbon-shaped morphology of the AuPdNaS_(2)crystal can be finely tuned to a thickness as low as 9.2 nm.Scanning transmission electron microscopy reveals the atomic arrangement,showcasing robust anisotropic features;thus,AuPdNaS_(2)exhibits distinct anisotropic phonon vibrations and electrical properties.The field-effect transistor constructed from AuPdNaS_(2)crystal demonstrates a pronounced anisotropic conductance(σ_(max)/σ_(min)=3.20)under gate voltage control.This investigation significantly expands the repertoire of NTMC materials and underscores the potential applications of AuPdNaS_(2)in nano-electronic devices.展开更多
基金supported by the National Natural Science Foundation of China(No.U2230123)the Science Foundation of the Science and Technology Department of Sichuan Province(No.22ZYZYTS0159)+4 种基金Science Foundation of China University of Petroleum(Nos.2462019QNXZ02,2462019BJRC007)Science Foundation of China University of Petroleum(East China)(No.2462020YXZZ018)Science and Technology Innovation Commission of Shenzhen(No.JSGG20210802153410031)Science and Technology Project of Nanshan District(No.NS_(2)021016)the Scientific Research Startup Fund for Discipline Leader of Huazhong University of Science and Technology Union Shenzhen Hospital(Nanshan Hospital)(No.YN2021002)。
文摘Carbon dots(CDs), a new building unit, have been revolutionizing the fields of biomedicine, bioimaging, and optoelectronics with their excellent physical, chemical, and biological properties. However, the difficulty of preparing excitation-dependent full-spectrum fluorescent CDs has seriously hindered their further research in fluorescence emission mechanisms and biomedicine. Here, we report full-spectrum fluorescent CDs that exhibit controlled emission changes from purple(380 nm) to red(613 nm) at room temperature by changing the excitation wavelength, and the excitation dependence was closely related to the regulation of sp2 and sp3 hybrid carbon structures by β-cyclodextrin-related groups. In addition,by regulating the content of β-cyclodextrin, the optimal quantum yields of full-spectrum fluorescent CDs were 8.97%, 8.35%, 7.90%, 9.69% and 17.4% at the excitation wavelengths of 340, 350, 390, 410 and 540 nm,respectively. Due to their excellent biocompatibility and color tunability, full-spectrum fluorescent CDs emitted bright and steady purple, blue, green, yellow, and red fluorescence in MCF-7 cells. Moreover, we optimized the imaging conditions of CDs and mitochondrial-specific dyes;and realized the mitochondrialtargeted co-localization imaging of purple, blue and green fluorescence. After that, we also explored the effect of full-spectrum fluorescent CDs in vivo fluorescence imaging through the intratumorally, subcutaneously, and caudal vein, and found that full-spectrum fluorescent CDs had good fluorescence imaging ability in vivo.
基金supported by the National Natural Science Foundation of China(Grant Nos.62588201 and 62275157)the National Key R&D Program of China(Grant No.2023YFF0719200)+3 种基金the Natural Science Foundation of Guangdong Province(Grant Nos.2023A1515012793 and 2024B1515020117)the 111 Project(Grant No.D18014)the Shuguang Program supported by the Shanghai Education Development Foundation and the Shanghai Municipal Education Commission,China(Grant No.18SG44)the Research Grants Council of Hong Kong through an Area of Excellence grant(Grant No.AoE/P-502/20).
文摘High-quality and real-time holographic imaging based on dynamically tunable metasurfaces has attracted immense interest.Despite remarkable progress,the complex electrical pattern designs and slowspeed near-field scanning terahertz(THz)microscopy systems have significantly hindered the development of real-time electrically tunable metasurface holography in the THz band.We propose and experimentally demonstrate an electrically tunable vanadium dioxide(VO_(2))-based active metasurface that can generate realtime bias-controlled holographic information via a THz focal plane imaging system.By elaborately designing“microladders”integrated with VO_(2)pads,the device exhibits low power consumption(∼0.8 W)and real-time imaging(∼4.5 s).The quantitative method is theoretically utilized to investigate the thermal parameters dependent thermodynamics of the“ladder”metasurface based on theoretical analysis with the aid of thermal modelling.The calculated dynamic response time based on the quantitative thermodynamic model agrees well with experimental results.Our study can be used to propel the development of THz electrically tunable metasurfaces for low-power-consumption dynamic,real-time displays,and information encryption,providing crucial insights for future optimization of VO_(2)-based electrothermally tunable holographic metasurfaces.
基金supported by the National Natural Science Foundation of China(11974156,12304223,12304019,and 62104017)Guangdong Innovative and Entrepreneurial Research Team Program(2019ZT08C044)+2 种基金Shenzhen Science and Technology Program(KQTD20190929173815000 and 20200925161102001)the Science,Technology and Innovation Commission of Shenzhen Municipality(ZDSYS20190902092905285)Guangdong Natural Science Foundation(2021A1515010049)。
文摘Two-dimensional noble transition metal chalcogenide(NTMC)semiconductors represent compelling building blocks for fabricating flexible electronic and optoelectronic devices.While binary and ternary compounds have been reported,the existence of quaternary NTMCs with a greater elemental degree of freedom remains largely unexplored.This study presents the pioneering experimental realization of a novel semiconducting quaternary NTMC material,AuPdNaS_(2),synthesized directly on Au foils through chemical vapor deposition.The ribbon-shaped morphology of the AuPdNaS_(2)crystal can be finely tuned to a thickness as low as 9.2 nm.Scanning transmission electron microscopy reveals the atomic arrangement,showcasing robust anisotropic features;thus,AuPdNaS_(2)exhibits distinct anisotropic phonon vibrations and electrical properties.The field-effect transistor constructed from AuPdNaS_(2)crystal demonstrates a pronounced anisotropic conductance(σ_(max)/σ_(min)=3.20)under gate voltage control.This investigation significantly expands the repertoire of NTMC materials and underscores the potential applications of AuPdNaS_(2)in nano-electronic devices.
