NANOCELLULOSE FOR PIEZOELECTRIC MATERIALS

KONRAD KLOCKARS

26.2.2015

PIEZOELECTRICITY – AN ELECTROMECHANICAL EFFECT

Piezoelectric effect: mechanical stress induces change in polarization density

Also converse effect: Applied electrical field induce mechanical strain

Observed in many natural materials, e.g. cellulose crystals

ZnO crystals conventionally used as piezoelectric material

Converse effect:

Displacement from induced polarization

Applied stress, caused by electric field

Transverse Piezoelectric constants

Bass P. S. et al. 2014. Electroact. Pol. Actuators and Devices (EAPAD)

Simplified formula!

PIEZOELECTRICITY IN CELLULOSEPolarizability/crystallinity of cellulose

Monoclinic/triclinic crystal unit in cellulose

Only shear constants present in cellulose

Alignment of cellulose chains important

Kim J.-H. et al. 2009. Journ. of Bionic Eng.

Csoka L. et al. 2012. ACS Macro Letters

NANOCRYSTALLINE CELLULOSE FILMS

Assembly using deposition plate and electric field Withdrawal rate and solvent evaporation

Field strength and frequency

Converse piezoelectric effect with AFM

Csoka L. et al. 2012. ACS Macro Letters

Hoeger I et al. 2011. Soft Matter

ELECTRO-ACTIVE PAPER

20-30 µm thick films with LiCl/DMAC, after stretching

Direct piezoelectric effect with picoammeter

Acoustic output from electrical signal generator

Kim J.-H. et al. 2009. Journ. of Bionic Eng.

Zhai L. et al. 2015. Cellulose

Abas Z. et al. 2014. SPIE proceedings

CELLULOSE AND…NCC as reinforcement in electroactive polymers

40 % larger rotation actuation(strain) with 1,5 % ncc

ZnO nanorods grown on cellulose substrate film 6 times larger piezoelectric constant

BaTiO3 embedded in cellulose fibres

Bass P. S. et al. 2014. Electroact. Pol. Actuators and Devices (EAPAD) Mahadeva S. K. et al. 2014. IEEE

CONCLUSIONS

The piezoelectric properties of cellulose can be utilized in many applications Speakers, vibration sensors, sound detectors

Voltage generators, energy harvesters

Microsensors, balances

Self-powering portable electronic devices

Biomedical devices, prosthetics, artificial muscles

Benefits Lightweight and flexible

Biodegradable and biocompatible

Low cost

REFERENCES1. Bass P. S., Baltzell M., Zhang L., Zhang D., Tu M. & Cheng Z. Electromechanical response of NCC-PEO composites. Electroactive

Polymer Actuators and Devices (EAPAD) 2014. San Diego, California, USA. 9.3.2014. SPIE Proceedings. Vol. 9056. DOI:10.1117/12.2044418

2. Bernardini F., Fiorentini V. & Vanderbilt D. Spontaneous polarization and piezoelectric constants of III-V nitrides. Physical Review B. 1997, vol 56. DOI: http://dx.doi.org/10.1103/PhysRevB.56.R10024

3. Csoka L., Hoeger I. C., Rojas O. J., Peszlen I., Pawlak J. J. & Peralta P. N. Piezoelectric Effect of Cellulose Nanocrystals Thin Films. ACS Macro Letters. 2012, vol. 1:7. pp. 867-870

4. Zhai L., Mun S., Gao X., Kim J. V. & Kim J. Cellulose electro-active paper fabricated by facile solvent exchange pretreatment and its physical and electromechanical properties. Cellulose. 2015. DOI: 10.1007/s10570-015-0553-y

5. Abas Z., Kim H. S., Zhai L. & Kim J. Experimental and numerical study of cellulose-based electro-active paper energy harvester. Nanosensors, Biosensors, and Info-Tech Sensors and Systems 2014, 90601G. San Diego, California, USA. 9.3.2014. SPIE Proceedings. Vol. 9060. DOI: 10.1117/12.2044639

6. Kim J.-H., Yun S., Kim J.-H., Kim J. Fabrication of Piezoelectric Cellulose Paper and Audio Application. Journal of Bionic Engineering. 2009, vol. 6:1. pp. 18-21. DOI:10.1016/S1672-6529(08)60096-7

7. Ko H.-U., Mun S., Min S.-K., Kim G.-W. & Kim J. Fabrication of Cellulose ZnO Hybrid Nanocomposite and Its Strain Sensing Behavior. Materials. 2014, vol 7. pp. 7000-7009. DOI:10.3390/ma7107000

8. Mahadeva S. K., Walus K. & Stoeber B. Fabrication and testing of piezoelectric hybrid paper for mems applications. 2014 IEEE 27th International Conference on Micro Electro Mechanical Systems (MEMS). San Francisco, California, USA. 26-30.1.2014. IEEE. DOI: 10.1109/MEMSYS.2014.6765717

9. Hoeger I., Rojas O. J., Efimenko K., Velev O. D. & Kelley S. S. Ultrathin film coatings of aligned cellulose nanocrystals from a convective-shear assembly system and their surface mechanical properties. Soft Matter. 2011, vol 7. pp. 1957-1967. DOI: 10.1039/C0SM01113D