- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Laser induced self-N-doped porous graphene as an electrochemical biosensor for femtomolar miRNA detection
摘要： We report a sensitive, yet low-cost biosensor based on laser induced graphene for femtomolar microRNA (miRNA) detection. Combined with the miRNA extraction and magnetic isolation process, the target miRNAs were purified for further detection using laser induced graphene sensor. The laser induced graphene was prepared by direct laser writing on commercial polyimide (PI) and patterned via a computer-aided design system as an electrode for electrochemical biosensing. We found that the laser reduction of PI resulted in nitrogen-doped porous graphene, not only improving its conductivity but also its sensitivity to nucleic acids. Preeclampsia specific miRNA hsa-miR-486-5p was magnetically purified and directly adsorbed on the surface of graphene electrode via graphene-miRNA affinity interaction. Surface attached miRNAs were then electrochemically quantified using [Fe(CN)6]3-/4- redox system. Our assay demonstrates detection of miRNA has-miR-486-5p up to concentrations as low as 10 fM with excellent reproducibility. Owing to its facile fabrication, low cost and high performance, the laser induced N-doped graphene biosensor presented here shows great potential for applications in detecting miRNA in biomedical applications.
关键词： electrochemical biosensor,porous graphene,laser induced graphene,nitrogen-doped,miRNA detection
更新于2025-09-23 15:21:01
-
Effects of background gases and pressure in pulsed laser deposition of Al-doped ZnO
摘要： Background gases (O2, He or Ar) with the pressure from ~ 10?3 Pa to 133.3 Pa are used in 355 nm laser deposition of Al-doped ZnO at room temperature. The effects of these gases and pressure on plasma formation are studied by optical emission spectroscopy (OES) and time of flight (TOF) measurement. The OES results show that the emission intensity of the species in O2 and Ar decrease slightly and then increase exponentially above ~ 5 Pa. The emission intensity in Ar is the highest, followed by emission in O2 whilst the emission in He is low and weakly depend on background gas pressure. TOF measurements indicate that the ion velocity decrease with increasing O2 and Ar pressure at about 5–10 Pa. The ion velocity is highest in He while the ion velocities in O2 and Ar are similar. Thin-film samples deposited in different gas at 2.6 Pa are amorphous, but those deposited at 133.3 Pa are crystalline and exhibit different morphologies and optical properties depending on type of gas. Samples deposited in O2 are highly transparent but those deposited in He and Ar contain nano and micron-sized structures with <50% transmittance. In addition, Zn crystallites are detected by X-ray diffraction.
关键词： Pulsed laser deposition,Background gases,Aluminum-doped zinc oxide,Pressure,Laser produced plasma,Nanostructured films
更新于2025-09-23 15:21:01
-
Pulse control in self-mode-locked 2.8???μm Er-doped fluoride fiber lasers
摘要： In this work, it had been demonstrated that the Er doped fluoride fiber laser emitting at 2.8 μm could accomplish the dark pulse based on self-mode-locked (SML). And the different distances of external feedback were also investigated in experiment. It was found that signal-noise ratio (SNR) of fundamental cavity repetition rate was decreased with increasing the distance of feedback. It was not only caused by increasing the length of cavity, but also influenced by the interaction between inter-cavity and external cavity. The fundamental cavity repetition rate of SML 2.8 μm pulsed laser could be controlled by adjusting distance of external feedback.
关键词： Cavity interaction,Self-mode-locked fiber laser,Dark pulse,Er-doped fluoride fiber
更新于2025-09-23 15:21:01
-
Synthesis and characterization of Sb doped SnO<sub>2</sub> for the photovoltaic applications: different route
摘要： Antimony doped tin oxide (ATO - Sn0.92O2:Sb0.08) nanoparticles were synthesized by different chemical routes such as Hydrothermal (HT), Sol-gel (SG) and Sonochemical (SC) methods. The XRD pattern of the samples shows that Sb ion successfully incorporated into Sn lattice without altering the crystal structure. Optical spectral analysis of the samples indicates more absorption in the visible region. The vibrational modes of the ATO nanoparticles were characterized by FTIR spectra. DSSCs were fabricated with the as-prepared ATO nanoparticles from different routes, Eosin-Y dye, I-/I3- redox couple as electrolyte. I-V characteristics of the as fabricated devices were recorded to estimate the efficiency of the device. Our results indicate the DSSC fabricated using the hydrothermally prepared material is to be considered as a suitable optical window material for dye and good electrolyte to achieve higher open circuit voltage (VOC). Further, the anode fabricated using the hydrothermally synthesized ATO nanoparticle gives good efficiency (η = 4.15%) comparing to the DSSCs fabricated using NPs synthesized via other methods. Hence, hydrothermally prepared material is to be considered as a suitable optical window materials for DSSCs.
关键词： antimony doped tin oxide,Dye sensitized solar cell,optical window
更新于2025-09-23 15:21:01
-
Two-micron all-fiberized passively mode-locked fiber lasers with high-energy nanosecond pulse
摘要： We report on mode-locked thulium-doped ?ber lasers with high-energy nanosecond pulses, relying on the transmission in a semiconductor saturable absorber (SESA) and a carbon nanotube (CNTs-PVA) ?lm separately. A section of an SMF–MMF–SMF structure multimode interferometer with a transmission peak wavelength of ～2003 nm was used as a wavelength selector to ?x the laser wavelength. When the SESA acted as a saturable absorber (SA), the mode-locked ?ber laser had a maximum output power of ～461 mW with a pulse energy of ～0.14 μJ and a pulse duration of ～9.14 ns. In a CNT-?lm-based mode-locked ?ber laser, stable mode-locked pulses with the maximum output power of ～46 mW, pulse energy of ～26.8 nJ and pulse duration of ～9.3 ns were obtained. To the best of our knowledge, our experiments demonstrated the ?rst 2 μm region ‘real’ SA-based dissipative soliton resonance with the highest mode-locked pulse energy from a ‘real’ SA-based all-?berized resonator.
关键词： high pulse energy,nanosecond pulse,Tm-doped ?ber laser,mode-locking
更新于2025-09-23 15:21:01
-
[IEEE 2019 IEEE 11th International Conference on Humanoid, Nanotechnology, Information Technology, Communication and Control, Environment, and Management ( HNICEM ) - Laoag, Philippines (2019.11.29-2019.12.1)] 2019 IEEE 11th International Conference on Humanoid, Nanotechnology, Information Technology, Communication and Control, Environment, and Management ( HNICEM ) - Voltage Characterization of Magnesium-doped Zinc Oxide by Electrodeposition Method for Solar Photovoltaic (PV) Cells
摘要： The research paper adapted the study of Rajpal and Kumar (2016). The Magnesium (Mg)-doped Zinc Oxide (ZnO) was prepared using the electrodeposition method. The samples obtained from the experiment were then collated to observe the photoconductivity value and the percentage of Voltage Regulation of the plates. Three (3) different tilt angle orientation were utilized in gathering the data of the Voltage Regulation percentage (%VR) and photoconductivity. The photoconductivity value acquired from the undoped plate is 0.7083 while, for the doped plates are 0.8438V, 0.6897V and 0.7204V. On the other hand, the %VR acquired for 0?, 13? and 20° were 1.283%, 5.820% and 3.456%, respectively. Moreover, the percent Battery Charge collated from the experiment are 0.39%, -1.20% and 1.11%, respectively. Further, the experiments showed that sun exposure and temperature have a significant impact on the electrical conductivity and output of the cells.
关键词： electrodeposition,tilt angles,Magnesium-doped,zinc oxide
更新于2025-09-23 15:21:01
-
Fe doped ZnO/BiVO4 heterostructure based large area, flexible, high performance broadband photodetector with ultrahigh quantum yield
摘要： Pristine ZnO has been widely explored for UV photodetectors; however it’s utility in broadband photodetectors is still an impediment due to absorbance in UV region only with low quantum efficiency and responsivity that can be accredited to high recombination rate of photo generated charge carriers. To address this issue, we report Fe metal doped 2D ZnO thin films through band gap engineering and 1D electrospun mixed inorganic monoclinic BiVO4 nanofibers heterostructure on ITO coated PET substrate based broadband photodetector (PD) with ultra-high responsivity and EQE values in comparison to PDs fabricated using expensive cleanroom techniques. BiVO4 plays the dual role of captivating photons in the visible and NIR regions and creating local electric fields at the interface of Fe doped ZnO (FZO)-BiVO4 heterostructure which helps in separation of electron-hole pairs. The robustness of the flexible PD was further examined under repeated conditions of bending cycles (upto 500) yielding stable response. The responsivity values obtained for UV, Visible and NIR lights are 7.35 A/W, 3.8 A/W and 0.18 A/W with very high EQE values of 2501.7 %, 851.2 % and 28.3 % respectively. The facile and cost-effective fabrication of the device with high performance gives a new approach for developing flexible electronics and high-performance optoelectronics devices.
关键词： Heterostructure,Broadband photodetector,Fe doped ZnO,BiVO4,ultrahigh quantum yield
更新于2025-09-23 15:21:01
-
Quantum Dot-Based Sensitization System for Boosted Photon Absorption and Enhanced Second Near-Infrared Luminescence of Lanthanide-Doped Nanoparticle
摘要： Efficient energy transfer is a promising strategy in overcoming the inherent limits of narrow band and weak absorption of lanthanide ions due to the nature of 4f-4f transitions. Herein, we introduce a nanoparticle-sensitized nanoparticle system where a near-infrared-emitting quantum dot (QD) is used as a sensitizer with broadband photon absorption for lanthanide-doped nanoparticle (LNP) to generate second near-infrared (NIR-II) emission. The NIR-II luminescence of Er3+-doped LNP by Ag2S QD sensitization displays an enhancement of ~17-fold in intensity and ~10-fold in brightness over bare LNP because of increased absorptivity and overall broadening of the absorption spectrum of LNP. Furthermore, QD-sensitized LNP system exhibits excellent photostability, and is able to improve the signal to noise ratio of tumor NIR-II imaging via in situ crosslinking of QD and LNP. The QD-sensitized LNP system for luminescence enhancement opens a potential avenue for efficient energy transfer in complex nanoparticle-nanoparticle systems.
关键词： Lanthanide-Doped Nanoparticle,Photon Absorption,Second Near-Infrared Luminescence,Quantum Dot,Sensitization System
更新于2025-09-23 15:21:01
-
Highly Stable Red Quantum Dot Light Emitting Diodes with Long T <sub/>95</sub> Operation Lifetime
摘要： Quantum dot light-emitting diodes (QLEDs) with excellent performances such as external quantum efficiency (EQE) and lifetime have almost met the requirement of low brightness display. However, the short operation lifetime under high brightness limits the application of QLEDs in outdoor displays and lightings. Herein, we report a highly efficient, stable red QLED by using of lithium and magnesium co-doped as well as magnesium oxide shell-coated zinc oxide nanoparticle layer as electron transport layer (ETL). The optimized QLED has a high peak EQE of 20.6%, a low efficiency roll-off at high current, and a remarkably long lifetime T95 > 11000 h at 1000 cd m-2, which indicates the realization of the most stable red QLED up to now. The improvement in the long-term stability of the QLED is attributed to the use of co-doped and shell-coated zinc oxide ETL with reduced electron injection to improve the charge balance in device.
关键词： EQE,QLEDs,electron transport layer,ETL,magnesium oxide shell-coated zinc oxide,Quantum dot light-emitting diodes,external quantum efficiency,lithium and magnesium co-doped,ZLMO@MO,lifetime
更新于2025-09-23 15:21:01
-
A K3ScSi2O7: Eu2+ based phosphor with broad-band NIR emission and robust thermal stability for NIR pc-LEDs
摘要： In this work, an Eu2+-doped K3ScSi2O7 (KSSO) NIR phosphor with broad-band NIR emission and robust thermal stability was designed and synthesized successfully. The crystal structure, luminescent properties, the mechanism of abnormal NIR emission, thermal stability and application to NIR pc-LEDs were investigated in detail.
关键词： NIR phosphor,Eu2+-doped,K3ScSi2O7,thermal stability,NIR pc-LEDs,broad-band emission
更新于2025-09-23 15:21:01