Synthesis and Characterization of Electrospun ZnO nanofiber layers for Organic Photovoltaic devices.

Project Title

Synthesis and Characterization of Electrospun ZnO nanofiber layers for Organic Photovoltaic devices.

Project Area of Specialization Biomedical EngineeringProject Summary

Life expectancy has globally increased and has resulted in an increased cost incurred upon healthcare monitoring of the aging population. World is considering the use of ubiquitous wireless network technologies such as WSNs/WBANs to devise a healthcare monitoring system for the elderly. One of the limiting factors in the use of WSNs/WBANs is limited capacity of batteries in a wireless sensor. We consider using Organic photovoltaic (OPV) devices due to their appealing properties such as low production costs, lightweight, semi-transparency and color tuning as well as mechanical flexibility, making them ideal candidates for solar energy harvesting (Kaltenbrunner et al., 2012) typically for WSN/WBANs.

The power conversion efficiency (PCE) of OPV devices has improved significantly over the recent years, and today reach values of almost above 16% for single-junction cells (Yuan et al., 2019) and 17.3% for tandem cells (Meng et al., 2018). Zinc oxide (ZnO) layers, for example made from nanoparticle solutions, are one of the most common metal oxide electron transport layers used in OPV devices (Liang et al., 2015). It has been demonstrated from previous studies, nanostructured interface layers can further improve the performance of OPV devices, either via improved light absorption in the cells (de Oliveira Hansen et al., 2013), or via improved charge extraction through the nanostructured contact layer (Mirsafaei et al., 2017). These effects lead to improved short-circuit current densities and fill factors in the solar cells. Through this project we demonstrate hybrid power mode for WSN/WBANs to increase dependability of such novel solutions for healthcare monitoring.

Luceño-Sánchez, J. A., Díez-Pascual, A. M., & Peña Capilla, R. (2019). Materials for photovoltaics: State of art and recent developments. International journal of molecular sciences, 20(4), 976. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6412461/

Ferrone, E., Araneo, R., Notargiacomo, A., Pea, M., & Rinaldi, A. (2019). ZnO nanostructures and electrospun ZnO–polymeric hybrid nanomaterials in biomedical, health, and sustainability applications. Nanomaterials, 9(10), 1449. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6835458/

Project Objectives

Following are the objectives of the project;

• To synthesize ZnO nanofibrous layers for OPV devices.
• Characterize the ZnO nano-layers/films for use in OPV cells/devices.
• Benchmarking of developed ZnO nanofiber layer for dependability analysis.

Project Implementation Method

ZnO nanofibers will be prepared by electrospinning of solution containing 4.8 g poly vinyl alcohol (PVA, Mw 70,000) in 60 ml deionized water. It will be stirred on a hot plate at 70 °C for 2 h. Then, 4.8 g of Zinc Oxide will be added to the solution. The solution then will be loaded into a plastic syringe and electrospun at a voltage of 18 kV with a flow rate of 0.2 ml per hour, while the distance between the collector and the needle is kept constant at 15 cm. To obtain aligned nanofibers, two steel electrodes with a gap of 1.5 cm on the collector will be used.

Performance of ZnO/PVA nanofibers based OPV devices will be compared with OPV devices manufactured through ordinary process of manufacturing and benchmarked.

Mohtaram, F., Borhani, S., Ahmadpour, M., Fojan, P., Behjat, A., Rubahn, H. G., & Madsen, M. (2020). Electrospun ZnO nanofiber interlayers for enhanced performance of organic photovoltaic devices. Solar Energy, 197, 311-316. https://www.sciencedirect.com/science/article/abs/pii/S0038092X19313003

Leach, M. K., Feng, Z. Q., Tuck, S. J., & Corey, J. M. (2011). Electrospinning fundamentals: optimizing solution and apparatus parameters. JoVE (Journal of Visualized Experiments), (47), e2494.https://www.jove.com/t/2494/electrospinning-fundamentals-optimizing-solution-apparatus

Benefits of the Project

ZnO based nano materials are a subject of expanding interest in this project because of their multifunctional properties and advantages such as high stability, piezoelectricity, semi-conductivity, low production cost, small size as well as their low toxicity and versatility in achieving diverse shapes. ZnO is used as a material that collect electrons and block holes where its structure plays a very significant role to determine the performance of the device such as power conversion efficiency, lifetime and stability.

Among the numerous manufacturing methods, electrospinning is turning into a mainstream technique for the production of metal oxide (ZnO) nanofibers. Zinc oxide is recognized as a bio-safe material. One of the most striking features of nanofibers is their exceptionally high surface area–to-volume ratio and high porosity, that makes it a robust and attractive match for many advanced applications. Implementation of this project offers ideal candidates for solar energy harvesting typically for WSN/WBANS that is cost effective too.

Huang, J., Yin, Z., & Zheng, Q. (2011). Applications of ZnO in organic and hybrid solar cells. Energy & Environmental Science, 4(10), 3861-3877. https://pubs.rsc.org/en/content/articlelanding/2011/ee/c1ee01873f#!divAbstract

Jiang, J., Pi, J., & Cai, J. (2018). The advancing of zinc oxide nanoparticles for biomedical applications. Bioinorganic chemistry and applications, 2018. https://www.hindawi.com/journals/bca/2018/1062562/

Technical Details of Final Deliverable

At the end of our project, we expect to have electrospun PVA/ZnO nanolayers. We shall detail the synthesis process of PVA/ZnO nnanofibrous film for its use in Organic Photovoltaic (OPV) devices. We shall provide benchmarking of our deliverable as a candidate for solar energy harvesting applications typically for WSN/WBANs.

Final Deliverable of the Project Hardware SystemCore Industry MedicalOther IndustriesCore Technology Wearables and ImplantablesOther Technologies Others, Clean TechSustainable Development Goals Good Health and Well-Being for People, Affordable and Clean Energy, Decent Work and Economic GrowthRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	80000
Laboratory glassware	Equipment	20	100	2000
Glass bottles- 20ml	Equipment	110	20	2200
PVA polymer	Equipment	500	12	6000
ZnO	Equipment	500	32	16000
Cellulose Acetate Polymer	Equipment	500	29	14500
Disposables	Equipment	5	500	2500
Steel Electrodes	Equipment	6	300	1800
Characterization (SEM testing)	Equipment	10	1000	10000
Characterization (FTIR testing)	Equipment	10	1500	15000
Transport	Miscellaneous	2	3500	7000
Print	Miscellaneous	3	1000	3000