Tutorial EN08—Processing and Device Optimization Strategies for High Efficiency Solar Cells

Halide perovskites are currently one of the hottest research topics due to their potential use in a wide variety of optoelectronic devices. Especially in the field of photovoltaics this material now outperforms most other thin-film solar-cell technologies, reaching efficiencies well above 20%.

In this tutorial, we will introduce materials researchers to the most important aspects related to the preparation of state-of-the-art perovskite solar cells. The first part will cover fundamental concepts regarding the preparation of perovskite films and discuss stability effects when tuning the elemental composition. The second part will cover reproducible fabrication protocols and design rules for single cell applications, with a special focus on charge-carrier recombination. Finally, in the third part, aspects regarding the preparation, challenges and prospects of perovskite-based tandem solar-cell devices will be examined. The overreaching goal of this tutorial is to provide a comprehensive overview regarding important aspects in material and device preparation; this will enable students and researchers who are new to this topic to pick up the necessary knowledge needed to participate in this exciting research field.

1:30 pm
Processing, Stabilizing and Detoxifying Perovskites
Yuanyuan Zhou, Brown University

The first session of this tutorial will discuss the fundamental materials science that governs the most outstanding issues of scalability, stability and toxicity in the commercialization of perovskite optoelectronics. First, fundamental understandings on the structure, formation and degradation of halide perovskites will be elaborated with specific examples from the literature. Then, typical materials-engineering strategies that mitigate these issues will be demonstrated. Finally, a perspective on the future directions in this research area will be provided.

2:30 pm BREAK

3:00 pm
How to Make Efficient Perovskite Solar Cells
Martin Stolterfoht, University of Potsdam

The second section will focus on conveying reproducible fabrication protocols for preparing p−i−n type perovskite solar cells with efficiencies above 20%. The optimization strategies are particularly focused on suppressing non-radiative interfacial recombination, which is the main bottleneck of today's perovskite solar cells. Necessary measurement techniques are introduced in this tutorial that will allow researchers to quantify recombination losses in their perovskite solar-cell stacks in order to identify the origin of efficiency losses.

4:00 pm
Perovskite-Based Multijunction Solar Cells
Jérémie Werner, University of Colorado Boulder

The third part of this course will cover relevant aspects related to the field of perovskite-based multijunction solar cells. First, a comprehensive overview will be given on how developments in stack design enabled the swift rise in efficiency from 0 to >28%, which took place in the last five years. Both all-perovskite as well as hybrid perovskite-based tandem solar cells will be introduced and the pros and cons discussed. Finally, the remaining challenges and future directions of this technology will be addressed.