Hydrogen production through solar water splitting is a clean solution to the actual energy demand. It can be carried out in a photoelectrochemical cell where a photoelectrode absorbs sunlight producing electron-hole pairs, then the charge carriers are collected separately to oxidize oxygen and reduce hydrogen from water. Several materials have been proposed and tested as photoelectrodes, being n-type oxide semiconductors the most suitable as photoanodes and p-type oxide semiconductors as photocathodes. However, the development of solar water splitting is still a challenge due to its low experimental efficiency. Therefore, a fundamental understanding of the charge carrier dynamics in oxide semiconductors is mandatory to improve the current efficiency. In that sense, time-resolved soft X-ray absorption spectroscopy is a technique capable to track the dynamics of electrons and holes at the same time with element selectivity, oxidation- and spin-state specificity making it adequate to give new insights of ultrafast carrier dynamics occurring in oxide semiconductors.
The project aims to develop of a novel methodology to explore ultrafast charge carrier dynamics in oxide semiconductors by time-resolved soft X-ray absorption spectroscopy. The main goal is to locally explore the transient electronic structure of p-type (Cu2O and CuO) and n-type (α-Fe2O3 and WO3) semiconductor thin films following NIR and UV excitation by monitoring the change of X-ray absorption spectrum at specific atomic edges (M- and L-edges). Additionally, the role of dopants as Ti in modifying the dynamics in α-Fe2O3 will be explored.
Hello, my name is Miguel, I am from Mexico and I am currently doing a PhD at the Max Born Institute in Berlin. My project is about studying ultrafast charge carrier dynamics in oxide semiconductors using high harmonic generation.
During my Bachelor studies in chemical engineering I developed a special interest in material science and spectroscopy, that led me to choose a project in photocatalysis. During this project I worked with many spectroscopic techniques for materials characterization, such as, UV-Vis, Raman, IR, X- rax fluorescence and X-ray photoelectron spectroscopy. After finishing my Bachelor´s degree I decided that I wanted to continue in the field of spectroscopy to understand better the light-matter interaction, therefore I continued my studies with a Master degree in optics. I took courses of ultrafast optics, nonlinear optics, applied spectroscopy and light matter interaction.
Since optics is a field of physics, I learned spectroscopy from a different point of view which complemented my perspective from chemistry.
For my master project I worked with an ultrafast Ti:sapphire laser to study nonlinear properties of materials, I found very interesting all the possible applications of ultrafast lasers.
After that, I was looking for a PhD project that could allow me to combine my knowledge and experience in chemistry and material science I acquired in my bachelor degree with my knowledge and experience in optics I got in my master degree. That took me to the position I am right now.
Apart from science, my hobbies are traveling and hiking in the nature, listening to music and going to music festivals, food particularly spicy food, practicing yoga, taking pictures and watching movies.
- PhD student (2021-present)
Max Born Institute, Berlin, Germany
Thesis: “Ultrafast charge carrier dynamics in oxide semiconductors probed by time-resolved x-ray spectroscopy”.
- Master of Science, Optics (2018-2020)
Centro de Investigaciones en Optica (A.C.), Leon, Guanajuato, Mexico
Thesis: “Linear and nonlinear optical study of organic and metal-organic single crystals grown by slow evaporation method”.
- Bachelor, Chemical engineering (2012-2017)
Universidad Autonoma de Chihuahua, Chihuahua, Chih., Mexico
Thesis: “Microwave-assisted green synthesis of Cu2O/TiO2 as photocatalyst for hydrogen production from glycerol”.