凯发_Emmanuel Kymakis

Speaker-Emmanuel Kymakis

Emmanuel Kymakis
University of Applied Sciences (TEI of Crete)

Emmanuel Kymakis is a full Professor and Head of Department of Electrical Engineering at the University of Applied Sciences (TEI of Crete), and also the Director of the interinstitutional M.Sc “Nanotechnology for Energy Applications”. He received the B.Eng. (First Class Honours) degree in Electrical Engineering & Electronics from Liverpool University in 1999 and the Ph.D. degree in Electrical Engineering from Cambridge University in 2003. He and Prof. Gehan Amaratunga are the inventors of the polymer-nanotube solar cell. Before joining TEI of Crete, he was a technical consultant offering engineering and consultancy services in the realization of photovoltaic and solar thermal power plants. His research is focused on the synthesis and solution processing of graphene and other two-dimensional materials with tailored properties, for the development of next generation, solution processed electronic and photovoltaics, compatible with roll-to-roll large area manufacturing methods. He has 100 SCI publications and over 6.000 citations with an h-index of 40. He has been an honorary lecturer at UConn and a recipient of an Isaac Newton and an EPSRC studentship. He was named as a 2014 ChemComm Emerging Investigator and has received two National Excellence Awards. He has served as a member of the general assembly of the Greek Foundation of Research & Innovation. He is currently the deputy leader of the Energy Generation WP of the FET-Flagship Initiative Graphene and a member of Engineering sectoral scientific council of the National Council for Research & Innovation of Greece.

Google Scholar Profile: https://scholar.google.gr/citations?user=AWrgzokAAAAJ&hl=el

Group website: http://nano.teicrete.gr/

Title：Graphene related materials in perovskite solar cells

SymposiumNew Energy

Starting Time

Ending Time

Abstract

The incorporation of graphene related materials (GRMs) have brought fresh air in the field of perovskite (PeSCs) solar cells. GRMs can simultaneously or individually optimize the photovoltaic parameters by taking advantage of their high charge mobility to provide additional percolated pathways for efficient exciton dissociation and charge transport in the photoactive layer, by adopting universal work function (WF) tunable charge transport layers, capable of providing a perfect energy match for either hole or electron extraction, and to fabricate flexible TCEs with tailored optoelectronic properties. In this context, GRMs have been successfully employed by my group in all the major components of a PeSC with a variety of functions [ChemSusChem 2016, 9, 3040; Adv. Energy Mater. 2017, 7, 1602120; Adv. Energy Mater. 2018, 8, 1702287; Energy Environ. Sci. 2018, 11, 1030].

In this talk, I will highlight our recent progress in improving the PeSCs lifetime through 2D interfacial engineering, and analysis of the degradation processes under prolonged illumination. The introduction of MoS2 flakes as a hole extraction interlayer in inverted PeSCs, resulted in significant improvement in the device lifetime, which is attributed to the stabilization of the hole transport layer/perovskite interface, inhibiting the bulk degradation process of the perovskite structure itself. In this way, encapsulated PeSCs with MoS2 interlayer retained 80% of their initial PCE (T80) after ~568 hours of continuous illumination at maximum power output in ambient conditions. This is, to date, the highest ever-reported lifetime for PeSCs tested in these conditions (Adv. Energy Mater 2018, 8, 1702287). Furthermore, solution-processed, high-quality electrochemically exfoliated graphene (EG) was employed as an effective dopant for the conventional HTM PTAA, to realize planar inverted PeSCs exhibiting extremely improved stability and PCE. EG doped PTAA as the HTL significantly improved hole extraction, while the device lifetime was also increased compared to the control device with F4-TCNQ doped PTAA. Moreover, EG was applied as a flexible ITO alternative TCE obtained by spray-coating, to realize efficient planar inverted PeSCs. EG based TCEs thickness was accurately optimized to improve the tradeoff between transparency and conductivity, achieving high PCE values of ~11% and 9.8% for rigid and flexible PeSCs, respectively. The PCE of the champion flexible PeSC was sustained at ~90% of their initial value, without increase in sheet resistance upon bending tests of 1000 bending cycles, proving that highly reproducible EG spray-coated TCEs hold enormous promise for both rigid and flexible large‐scale PeSCs, bringing the gap between graphene‐based and ITO electrodes, for next generation flexible PeSCs.