Micro/Nano Mechanical Systems Lab–Class#8 · 2018-02-09 · Lab #3 –Instruction (I) Instructions to pattern design 1. Draw your pattern using PPT (recommended), and save the pattern

Microsystems LaboratoryUC-Berkeley, ME Dept.

1Liwei Lin, University of California at Berkeley

Micro/Nano Mechanical SystemsLab – Class#8

Lecturer: Caiwei Shen

Advised by Liwei LinProfessor, Dept. of Mechanical Engineering

Co-Director, Berkeley Sensor and Actuator CenterThe University of California, Berkeley, CA94720

e-mail: [email protected]://www.me.berkeley.edu/~lwlin

Microsystems LaboratoryUC-Berkeley, ME Dept.

2Liwei Lin, University of California at Berkeley

Outline

Micro/nano technologies for energy storage• Lithium ion battery• Supercapacitor

– Nanostructures for supercapacitors• Carbon nanotubes• Graphene

– Design of working supercapacitors

Lab #3 (Supercapacitors based on Laser Induced Graphene)

Microsystems LaboratoryUC-Berkeley, ME Dept.

3Liwei Lin, University of California at Berkeley

Supercapacitor (I) Working principle

• Electrochemical double-layer effect

RiC+ C- int erface 0AC

d

Typical Electrode: Porous Carbon, Carbon nanotube, Graphene…

http://en.wikipedia.org/wiki/Supercapacitor

Microsystems LaboratoryUC-Berkeley, ME Dept.

4Liwei Lin, University of California at Berkeley

Supercapacitor (II) Working principle

• Pseudo capacitive effect

(V) dQCdV

RiC+ C-Rk Rk

Typical Electrode: Metal Oxide, Conducting Polymer… http://en.wikipedia.org/wiki/Supercapacitor

Microsystems LaboratoryUC-Berkeley, ME Dept.

5Liwei Lin, University of California at Berkeley

Nanostructures for Supercapacitors Design of nanostructures for supercapacitors

Nature Mater. 7, 845–854 (2008).

Microsystems LaboratoryUC-Berkeley, ME Dept.

6Liwei Lin, University of California at Berkeley

Carbon nanotubes & Graphene

Carbon nanotubes

Graphene

http://wiki.seg.org/wiki/Carbon

Microsystems LaboratoryUC-Berkeley, ME Dept.

7Liwei Lin, University of California at Berkeley

Carbon nanotubes (I) For supercapacitors electrodes

• Reasonable surface area (100-500 m2/g)• High electrical conductivity• High mechanical and electrochemical stability – perfect scaffold

Microsystems LaboratoryUC-Berkeley, ME Dept.

8Liwei Lin, University of California at Berkeley

Carbon nanotubes (II) Vertically aligned carbon nanotubes (VACNT) for hybrid

supercapacitor applications

Y. Jiang, L. Lin, et al., "Uniformly Embedded Metal Oxide Nanoparticles in Vertically Aligned Carbon Nanotube Forests as Pseudocapacitor Electrodes for Enhanced Energy Storage," Nanoletters Vol. 13, pp. 3524-3530, 2013.

• Grown on silicon and Fe/Al/Mo stacking layer • Electrodeposition of nickel nanoparticles • Specific capacitance of 1.26 F/cm3, 5.7 X higher than pure CNT

Microsystems LaboratoryUC-Berkeley, ME Dept.

9Liwei Lin, University of California at Berkeley

Carbon nanotubes (III) VACNT + ALD RuO2

R. Warren, L. Lin, et al., "Highly Active Ruthenium Oxide Coating via ALD and Electrochemical Activation in Supercapacitor Applications," Journal of Materials Chemistry - A, Vol. 3, 15568-15575, 2015.

• Atomic layer deposition (ALD) of ruthenium oxide• Specific capacitance of 644 F/g• 170 X higher than pure CNT

Microsystems LaboratoryUC-Berkeley, ME Dept.

10Liwei Lin, University of California at Berkeley

Carbon nanotubes (IV) VACNT + ALD TiS2

X. Zang, L. Lin, et al., "Titanium Disulfide Coated Carbon Nanotube Hybrid Electrodes Enable High Energy Density Symmetric Pseudocapacitors," Advanced Materials, Vol. 30, 1704754, 2018.

• Atomic layer deposition (ALD) of titanium disulfide• Specific capacitance of 195 F/g, 3V in aqueous electrolyte• 60.9 Wh/kg

Microsystems LaboratoryUC-Berkeley, ME Dept.

11Liwei Lin, University of California at Berkeley

Graphene properties

Charge carrier mobility ~200,000 cm2/V s

Thermal conductivity ~5000 W/m K

Transparency ~97.4%Specific surface

area ~2630 m2/g

Young’s modulus ~1 TPaTensile strength ~1100 GPa

Microsystems LaboratoryUC-Berkeley, ME Dept.

12Liwei Lin, University of California at Berkeley

Graphene production Mechanical exfoliation from graphite Chemical vapor deposition Reduction from graphite oxide Produced from polymer

Microsystems LaboratoryUC-Berkeley, ME Dept.

13Liwei Lin, University of California at Berkeley

Graphene production Reduction from graphite oxide

http://www.microwavejournal.com/blogs/9-pat-hindle-mwj-editor/post/18722-idtechex-forecasts-a-100-million-graphene-market-in-2018

Apply laser

• Graphite oxide: compound of carbon, oxygen, and hydrogen in variable ratios

• 0.7~1.1 nm between layers (0.335 nm for graphite)

• Weak van der Waals bonds

• Hydrophilic

Microsystems LaboratoryUC-Berkeley, ME Dept.

14Liwei Lin, University of California at Berkeley

Graphene production Reduction from graphite oxide by laser

Gao, et al., Nature Nanotech., 2011

El-Kady, et al., Science, 2012

High conductivity: 1700 S/m, High surface area: 1500 m2/g (2600 m2/g for ideal graphene)

Microsystems LaboratoryUC-Berkeley, ME Dept.

15Liwei Lin, University of California at Berkeley

Graphene production Reduction from polymer by laser

NATURE COMMUNICATIONS | 5:5714 | DOI: 10.1038/ncomms6714

Microsystems LaboratoryUC-Berkeley, ME Dept.

16Liwei Lin, University of California at Berkeley

Design of working supercapacitors Electrode configurations for supercapacitors

• In-plane vs. sandwich

C. Shen, L. Lin, et al., IEEE Journal of Microelectromechanical Systems, Vol. 26, pp. 949-965, 2017.

Microsystems LaboratoryUC-Berkeley, ME Dept.

17Liwei Lin, University of California at Berkeley

Design of working supercapacitors On-chip micro supercapacitors

Microsystems LaboratoryUC-Berkeley, ME Dept.

18Liwei Lin, University of California at Berkeley

Design of working supercapacitors Electrode configurations for supercapacitors

• Coaxial fiber

C. Shen, L. Lin, et al., ACS Applied Materials & Interfaces, Vol. 9, pp. 39391-39398, 2017.

Microsystems LaboratoryUC-Berkeley, ME Dept.

19Liwei Lin, University of California at Berkeley

Design of working supercapacitors Electrode configurations for supercapacitors

• Woven fabrics

C. Shen, L. Lin, et al., Scientific Reports, Vol. 7, 14324, 2017.

Microsystems LaboratoryUC-Berkeley, ME Dept.

20Liwei Lin, University of California at Berkeley

Design of working supercapacitors Electrode configurations for supercapacitors

• Woven fabrics

C. Shen, L. Lin, et al., Scientific Reports, Vol. 7, 14324, 2017.

Energy harvester

Rectifier

ResistorLED

Microsystems LaboratoryUC-Berkeley, ME Dept.

21Liwei Lin, University of California at Berkeley

Lab #3 Supercapacitors based on laser induced graphene

• Design your own electrode pattern (before the lab!)• Discuss with GSI to verify the pattern• Scribe out the pattern on polymer using laser• Apply polymer based electrolyte• Make electrical connection, charge and light up a LED

In your reports• Introduction• Electrode pattern design• Results (photo of the device, charging process,

powering a LED for how long)• Discussion (Capacitance, voltage, how to optimize)

Microsystems LaboratoryUC-Berkeley, ME Dept.

22Liwei Lin, University of California at Berkeley

Lab #3 – Instruction (I) Instructions to pattern design

1. Draw your pattern using PPT (recommended), and save the pattern as .jpg file

2. Use black blocks to build the pattern, check the size, limit all patterns within a 2” x 2” or 5cm x 5cm square, the smallest feature size should be >0.02” or 0.5mm

Microsystems LaboratoryUC-Berkeley, ME Dept.

23Liwei Lin, University of California at Berkeley

Lab #3 – Instruction (II) Instructions to pattern design

3. Copy your pattern, then– Use a semi-transparent color to indicate areas to be covered with

electrolyte– Use another color to indicate areas used for electrical contact– Use dashed lines to indicate lines to be cut

Microsystems LaboratoryUC-Berkeley, ME Dept.

24Liwei Lin, University of California at Berkeley

Lab #3 – Instruction (III) Instructions to pattern design

4. Send the original design pattern and colored pattern to GSI before the lab through the email: [email protected]

5. GSI will comment on the designs before printing them out using laser