Title: Unconventional Energy Storage Devices

Speaker: Dr. Shahab Ahmad, Cambridge University

Abstract: Ever growing energy demands require versatile energy solutions. Emerging autonomous electronic devices require increasingly compact energy generation and storage solutions. In this seminar talk I will give an insight about my research work on unconventional energy storage devices, their challenges and future-scope.

One of the most fascinating paradigm shifts in modern electronics is the fabrication of soft and flexible electronic devices. This development is fuelled by continuous search for more compact and intuitive flexible electronics, medical implants, and the emergence of the “Internet of Things.” While considerable progress has been made in the fabrication of flexible and stretchable circuits, the flexible batteries needed to power these devices remain challenging. I will be talking about my recent work on Ultra-flexible Li-ion batteries, composed of 3D CNT structures, for flexible electronic applications.

In recent years, 3D lead halide perovskites have been studied intensively for use in solar cells because of their high conversion efficiencies of up to 22%. More recently, reports have suggested perovskites can also be used as anode materials in Li-ion batteries. However, these functionalities have never been combined in a single solar-battery device. Here I present a first report, that polycrystalline metal-halide-based 2D perovskite materials can combine both photo-charging and energy storage functionalities simultaneously. In this seminar I will be discussing about fundamental energy storage mechanisms in perovskites, and how their optical properties can be used to simultaneously achieve photo-charging and Li-ion storage in a device, termed as Photo-battery.

References:

1. Shahab Ahmad, D. Copic, C. George and Michael De Volder. “Hierarchical Assemblies of Carbon Nanotubes for Ultraflexible Li-ion Batteries”, Advanced Materials 28 (2016) 6705–6710.

2. National Renewable Energy Laboratory, “Efficiency chart,” 2017. https://www.nrel.gov/pv/assets/images/efficiency-chart.png

3. Shahab Ahmad , C. George, D. Beesley, Jeremy J Baumberg and Michael De Volder. “Photo-Rechargeable Organo-Halide Perovskite Batteries”, Nature (Under Revision) 2017.

4. Shahab Ahmad, P.K. Kanaujia, H.J. Beeson, A.Abate, F. Deschler, D. Credgington, Ullrich Steiner, G Vijaya Prakash and Jeremy J Baumberg. “Strong photocurrent from 2D excitons in solution-processed stacked perovskite semiconductor sheets”, ACS Applied Materials & Interfaces 7 (2015) 25227.

5. A. Sadhanala, Shahab Ahmad, et. al. “Blue-Green Colour Tunable Solution Processable Organolead Chloride-Bromide Mixed Halide Perovskites for Optoelectronic Applications”, Nano Letters 15 (2015) 6095.

6. Shahab Ahmad, P. K. Kanaujia, W. Niu, Jeremy J. Baumberg and G. Vijaya Prakash, “In-situ intercalation dynamics in inorganic-organic layered perovskite thin films”, ACS Applied Materials and Interfaces 6 (2014) 10238.