Carbon quantum dots (CQDs) have been used in memristors due to their attractive optical and electronic properties, which are considered candidates for brain-inspired computing devices. In this work, the performance of...Carbon quantum dots (CQDs) have been used in memristors due to their attractive optical and electronic properties, which are considered candidates for brain-inspired computing devices. In this work, the performance of CQDs-based memristors is improved by utilizing nitrogen-doping. In contrast, nitrogen-doped CQDs (N-CQDs)-based optoelectronic memristors can be driven with smaller programming voltages (−0.6 to 0.7 V) and exhibit lower powers (78 nW/0.29 µW). The physical mechanism can be attributed to the reversible transition between C–N and C=N with lower binding energy induced by the electric field and the generation of photogenerated carriers by ultraviolet light irradiation, which adjusts the conductivity of the initial N-CQDs to implement resistance switching. Importantly, the convolutional image processing based on various cross kernels is efficiently demonstrated by stable multi-level storage properties. An N-CQDs-based optoelectronic reservoir computing implements impressively high accuracy in both no noise and various noise modes when recognizing the Modified National Institute of Standards and Technology (MNIST) dataset. It illustrates that N-CQDs-based memristors provide a novel strategy for developing artificial vision system with integrated in-memory sensor and computing.展开更多
Nitrogen-doped carbon quantum dots(N-CQDs)are nanocomposites that can be synthesized by the hydrothermal method.In this work,N-CQDs with the size of 3.2±1.7 nm was prepared from 1 g citric acid and 2 g urea precu...Nitrogen-doped carbon quantum dots(N-CQDs)are nanocomposites that can be synthesized by the hydrothermal method.In this work,N-CQDs with the size of 3.2±1.7 nm was prepared from 1 g citric acid and 2 g urea precursor in 10 mL water.Electrochemiluminescence(ECL)of the prepared N-CQDs with K2S2O8 as a coreactant was found to reach a high ECL efficiency up to 109%relative to that of the Ru(bpy)_(3)^(2+)/K_(2)S_(2)O_(8),coreactant system,revealing their great potential for electroanalysis.It is probably because that N elements were doped well in this N-CQDs and increased presence of surface states per mass of N-CQDs.From the spooling ECL spectroscopy,it can be found that the ECL spectra exhibited both a red shift compared with their photoluminescence(PL)spectrum and a wavelength shift during the potentiodynamic scan in the ECL evolution and devolution processes,due to various emissive excited states of N-CQDs leading to higher ECL efficiency.This work gives an insight into development of high ECL efficiency N-CQDs for bioanalytical and light emitting applications.展开更多
基金financially supported by the National Key Research and Development Program of China(No.2022YFE0139100)International cooperative research project of Jiangsu province(No.BZ2022008)+3 种基金the National Natural Science Foundation Project of China(No.62175028)Program 111_2.0 in China(No.BP0719013)Leading Technology of Jiangsu Basic Research Plan(No.BK20192003)Postgraduate Research & Practice Innovation Program of Jiangsu Province,the Fundamental Research Funds for the Central Universities(No.KYCX23_0254).
文摘Carbon quantum dots (CQDs) have been used in memristors due to their attractive optical and electronic properties, which are considered candidates for brain-inspired computing devices. In this work, the performance of CQDs-based memristors is improved by utilizing nitrogen-doping. In contrast, nitrogen-doped CQDs (N-CQDs)-based optoelectronic memristors can be driven with smaller programming voltages (−0.6 to 0.7 V) and exhibit lower powers (78 nW/0.29 µW). The physical mechanism can be attributed to the reversible transition between C–N and C=N with lower binding energy induced by the electric field and the generation of photogenerated carriers by ultraviolet light irradiation, which adjusts the conductivity of the initial N-CQDs to implement resistance switching. Importantly, the convolutional image processing based on various cross kernels is efficiently demonstrated by stable multi-level storage properties. An N-CQDs-based optoelectronic reservoir computing implements impressively high accuracy in both no noise and various noise modes when recognizing the Modified National Institute of Standards and Technology (MNIST) dataset. It illustrates that N-CQDs-based memristors provide a novel strategy for developing artificial vision system with integrated in-memory sensor and computing.
基金funded by the Natural Sciences and Engineering Research Council of Canada(NSERC,DG RGPIN-2013-201697,DG RGPIN-2018-06556,DG RGPIN-2023-05337,SPG STPGP-2016-493924(Z.D.))New Frontiers in Research Fund,NFRFR-2021-00272(Z.D.)+2 种基金National Natural Science Foundation of China(22004034(X.Q.))Natural Science Foundation of Hunan Province(China)(2020JJ5226(X.Q.))China Scholarship Council(CSC,201908430010(X.Q.)).
文摘Nitrogen-doped carbon quantum dots(N-CQDs)are nanocomposites that can be synthesized by the hydrothermal method.In this work,N-CQDs with the size of 3.2±1.7 nm was prepared from 1 g citric acid and 2 g urea precursor in 10 mL water.Electrochemiluminescence(ECL)of the prepared N-CQDs with K2S2O8 as a coreactant was found to reach a high ECL efficiency up to 109%relative to that of the Ru(bpy)_(3)^(2+)/K_(2)S_(2)O_(8),coreactant system,revealing their great potential for electroanalysis.It is probably because that N elements were doped well in this N-CQDs and increased presence of surface states per mass of N-CQDs.From the spooling ECL spectroscopy,it can be found that the ECL spectra exhibited both a red shift compared with their photoluminescence(PL)spectrum and a wavelength shift during the potentiodynamic scan in the ECL evolution and devolution processes,due to various emissive excited states of N-CQDs leading to higher ECL efficiency.This work gives an insight into development of high ECL efficiency N-CQDs for bioanalytical and light emitting applications.
