Identifier: TDX:3007
Authors: Jiménez López, Jesús
Abstract:
Photovoltaics have become one of the most popular renewable source of energy. Photovoltaic technologies transform
sunlight into electricity, and they are also available worldwide, and they do not depend on the conversion of motive
power, making this technology quite easy to implement. Nowadays, silicon is still the most used material for
photovoltaics. Anyway, new photovoltaic technologies have emerged as alternatives to silicon, as they are cheaper,
easier to process, and, they are possible to use on flexible substrates. Among them, lead halide perovskites have
become one of the most popular choice in the scientific community, due to the great properties that this material
presents. While efficiencies have risen above 25%, which is close to their maximum theoretical limit, there is still
debate about the processes happening in the device. In this thesis, we try to gain insight into charge carrier processes
from their generation to their recombination at both perovskite interfaces, and also in the bulk of the material. Using
advanced characterization techniques, such as transient photovoltage (TPV), transient photocurrent (TPC), charge
extraction (CE), and femtosecond transient absorption spectroscopy (fsTA) we obtained important findings about
charge carrier losses, and artifacts affecting charge carrier recombination in functional devices that lead to lower power
conversion efficiencies.