Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

System for reducing graphene oxide by using femtosecond laser pulse sequence

A femtosecond laser and pulse sequence technology, which is applied in the field of femtosecond laser applications, can solve the problems of low reduction degree of graphene oxide, ablation damage of graphene oxide, and insignificant thermal effect, so as to improve energy utilization rate and reduction degree. High, obvious thermal effect

Active Publication Date: 2020-01-07
TSINGHUA UNIV +1
View PDF12 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the disadvantage of femtosecond laser is that its thermal effect is not obvious, and the reduction of graphene oxide needs to use the thermal effect of laser, so the reduction degree of femtosecond laser to graphene oxide is not high
However, the effect of adjusting the degree of reduction by adjusting the power is limited. When the power is high, graphene oxide is easily damaged by ablation, which affects the use after reduction.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • System for reducing graphene oxide by using femtosecond laser pulse sequence
  • System for reducing graphene oxide by using femtosecond laser pulse sequence
  • System for reducing graphene oxide by using femtosecond laser pulse sequence

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] Turn on the femtosecond laser 1 to generate femtosecond laser, adjust the spot diameter to 8mm through the aperture 2, and adjust the laser power to 200μW through the attenuation plate 3. The computer 13 controls the pulse shaper 5 to compress the femtosecond laser pulse to obtain the conversion limit pulse, and then utilizes the multi-pulse generation function of the pulse shaper 5 to modify the parameters of the pulse sequence and set the number of pulses in the pulse sequence to 3 The pulse time domain interval is 500fs, the intensity is equal intensity, and the time domain waveform of the pulse is observed in real time until the required pulse waveform is obtained. The time domain waveform is as follows figure 2 shown. Set the scanning speed of the translation stage 10 to 2 μm / s, and the interval to 1 μm, and open the electronically controlled shutter 4 to restore the GO 9 by laser scanning. After scanning, GO 9 was reduced with a single pulse laser to compare the...

Embodiment 2

[0022] The computer 13 controls the pulse shaper 5 to compress the pulses to obtain the conversion limit pulse, and then utilizes the multi-pulse generation function of the pulse shaper 5 to modify the parameters of the pulse sequence, and the number of pulses in the pulse sequence is set to 5. The domain interval is 500fs, the intensity is equal intensity, and the time domain waveform of the pulse is observed in real time until the desired pulse waveform is obtained. Set the scanning speed of the translation stage 10 to 2 μm / s, and the interval to 1 μm, and open the electronically controlled shutter 4 to restore the GO 9 by laser scanning. After reduction by the modulated five-pulse sequence, the oxygen content of graphene oxide was only reduced by about 8%, and there was no local excessive ablation phenomenon. Example 2 shows that there are too many sub-pulses in the equal-intensity pulse sequence, the energy is too dispersed, and the electronic excitation effect on graphene...

Embodiment 3

[0024] The computer 13 controls the pulse shaper 5 to compress the pulse to obtain the conversion limit pulse, and then utilizes the phase function modulation function of the pulse shaper 5 to select a polynomial phase function. The mathematical form of the phase function is:

[0025]

[0026] in, It is a phase offset and has no effect on the waveform of the pulse; Group delay, this parameter only affects the position of the laser pulse in the time domain without affecting the waveform; is the group delay dispersion, which controls the linear chirp of the pulse and affects the pulse width; For the third-order dispersion, this parameter controls the second-order chirp of the pulse and affects the pulse shape. Set the phase function of the pulse shaper 5, The time-domain waveform of the pulse is observed in real time. Under this parameter, a pulse sequence with decreasing intensity is obtained. The number of measurable sub-pulses is 4. The time-domain waveform is as f...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a system for reducing graphene oxide by using a femtosecond laser pulse sequence, and belongs to the technical field of femtosecond laser application. According to the system,a pulse shaper is used for modulating time domain waveform of femtosecond laser, the modulated laser is propagated through an optical system and focused on the surface of graphene oxide through a lens, processing of the graphene oxide is achieved, and a graphene-like structure is generated because of reduction reaction in a processed area. According to the system, the pulse shaper is used for adjusting a phase function corresponding to the femtosecond laser time domain waveform, the femtosecond laser time domain waveform is modulated into complex waveforms such as an equal-strength multi-pulse sequence and a strength-decreasing multi-pulse sequence from a single pulse, the reduction effect of graphene oxide is optimized, and the reduction degree is increased. The advantages of the femtosecond laser reduction on graphene oxide is achieved better, the advantages of high processing precision, high energy utilization rate and high reduction degree of graphene oxide are achieved, and a feasible method for preparing carbon-based micro-nano devices based on the graphene oxide is provided.

Description

technical field [0001] The invention relates to a system for reducing graphene oxide by using a femtosecond laser pulse sequence, and belongs to the technical field of femtosecond laser application. Background technique [0002] Graphene is a widely used two-dimensional material with excellent mechanical, electrical, and chemical properties. Graphene can be synthesized by many methods, such as chemical method, mechanical exfoliation method, deposition method and so on. Graphene oxide is a derivative of graphene, which can be prepared by the oxidation reaction of graphite. Compared with graphene, graphene oxide has a lot of oxygen-containing functional groups in its structure, which makes their properties completely different. For example, graphene It is a good conductor, but graphene oxide does not conduct electricity. It is a stable and efficient way to obtain graphene by reducing graphene oxide by different methods. The commonly used methods include thermal method and ch...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): C01B32/184H01S3/00
CPCC01B32/184H01S3/005
Inventor 姜澜郭恒闫剑锋
Owner TSINGHUA UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com