Since selective detection of multiple narrow spectral bands in the near-infrared(NIR)region still poses a fundamental challenge,we have,in this work,developed NIR photodetectors(PDs)using photon upconversion nanocryst...Since selective detection of multiple narrow spectral bands in the near-infrared(NIR)region still poses a fundamental challenge,we have,in this work,developed NIR photodetectors(PDs)using photon upconversion nanocrystals(UCNCs)combined with perovskite films.To conquer the relatively high pumping threshold of UCNCs,we designed a novel cascade optical field modulation strategy to boost upconversion luminescence(UCL)by cascading the superlensing effect of dielectric microlens arrays and the plasmonic effect of gold nanorods,which readily leads to a UCL enhancement by more than four orders of magnitude under weak light irradiation.By accommodating multiple optically active lanthanide ions in a core-shell-shell hierarchical architecture,developed PDs on top of this structure can detect three well-separated narrow bands in the NIR region,i.e.,those centered at 808,980,and 1540 nm.Due to the large UCL enhancement,the obtained PDs demonstrate extremely high responsivities of 30.73,23.15,and 12.20 AW^(−1) and detectivities of 5.36,3.45,and 1.91×10^(11) Jones for 808,980,and 1540 nm light detection,respectively,together with short response times in the range of 80-120 ms.Moreover,we demonstrate for the first time that the response to the excitation modulation frequency of a PD can be employed to discriminate the incident light wavelength.We believe that our work provides novel insight for developing NIR PDs and that it can spur the development of other applications using upconversion nanotechnology.展开更多
The self-assembling properties, stability, and dynamics of hybrid nanocarriers （gold nanoparticles （AuNPs） functionalized with cysteine-based peptides） in solution are studied through a series of classical molecul...The self-assembling properties, stability, and dynamics of hybrid nanocarriers （gold nanoparticles （AuNPs） functionalized with cysteine-based peptides） in solution are studied through a series of classical molecular dynamics simulations based on a recently parametrized reactive force field. The results reveal, at the atomic level, all the details regarding the peptide adsorption mechanisms, nanoparticle stabilization, aggregation, and sintering. The data confirm and explain the experimental findings and disclose aspects that cannot be scrutinized by experiments. The biomolecules are both chemisorbed and physisorbed; self-interactions of the adsorbates and formation of stable networks of inter- connected molecules on the AuNP surfaces limit substrate reconstructions, protect the AuNPs from the action of the solvent, and prevent direct interactions of the gold surfaces. The possibility of agglomeration of the functionalized nanoparticles, compared with the sintering of the bare supports in a water solution, is demonstrated through relatively long simulations and fast steered dynamics. The analysis of the trajectories reveals that the AuNPs were well stabilized by the peptides. This prevented particle sintering and kept the particles far apart; however, part of their chains could form interconnections （crosslinks） between neighboring gold vehicles. The excellent agreement of these results with the literature confirm the reliability of the method and its potential application to the modeling of more complex materials relevant to the biomedical sector.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11974143,11874181,61822506,and U1801253)the Special Project of the Province-University Co-constructing Program of Jilin Province(SXGJXX2017-3)+5 种基金support from the Swedish Research Council(VR 2016-03804)the Carl Tryggers Foundation(CTS 18:229)the AForsk Foundation(19-424)the Olle Engkvists Foundation(200-0514)support from the Swedish Research Council(VR 2016-03319)support from the Swedish Foundation for Strategic Research(SSF ITM17-0491).
文摘Since selective detection of multiple narrow spectral bands in the near-infrared(NIR)region still poses a fundamental challenge,we have,in this work,developed NIR photodetectors(PDs)using photon upconversion nanocrystals(UCNCs)combined with perovskite films.To conquer the relatively high pumping threshold of UCNCs,we designed a novel cascade optical field modulation strategy to boost upconversion luminescence(UCL)by cascading the superlensing effect of dielectric microlens arrays and the plasmonic effect of gold nanorods,which readily leads to a UCL enhancement by more than four orders of magnitude under weak light irradiation.By accommodating multiple optically active lanthanide ions in a core-shell-shell hierarchical architecture,developed PDs on top of this structure can detect three well-separated narrow bands in the NIR region,i.e.,those centered at 808,980,and 1540 nm.Due to the large UCL enhancement,the obtained PDs demonstrate extremely high responsivities of 30.73,23.15,and 12.20 AW^(−1) and detectivities of 5.36,3.45,and 1.91×10^(11) Jones for 808,980,and 1540 nm light detection,respectively,together with short response times in the range of 80-120 ms.Moreover,we demonstrate for the first time that the response to the excitation modulation frequency of a PD can be employed to discriminate the incident light wavelength.We believe that our work provides novel insight for developing NIR PDs and that it can spur the development of other applications using upconversion nanotechnology.
文摘The self-assembling properties, stability, and dynamics of hybrid nanocarriers （gold nanoparticles （AuNPs） functionalized with cysteine-based peptides） in solution are studied through a series of classical molecular dynamics simulations based on a recently parametrized reactive force field. The results reveal, at the atomic level, all the details regarding the peptide adsorption mechanisms, nanoparticle stabilization, aggregation, and sintering. The data confirm and explain the experimental findings and disclose aspects that cannot be scrutinized by experiments. The biomolecules are both chemisorbed and physisorbed; self-interactions of the adsorbates and formation of stable networks of inter- connected molecules on the AuNP surfaces limit substrate reconstructions, protect the AuNPs from the action of the solvent, and prevent direct interactions of the gold surfaces. The possibility of agglomeration of the functionalized nanoparticles, compared with the sintering of the bare supports in a water solution, is demonstrated through relatively long simulations and fast steered dynamics. The analysis of the trajectories reveals that the AuNPs were well stabilized by the peptides. This prevented particle sintering and kept the particles far apart; however, part of their chains could form interconnections （crosslinks） between neighboring gold vehicles. The excellent agreement of these results with the literature confirm the reliability of the method and its potential application to the modeling of more complex materials relevant to the biomedical sector.
