By summerstudent Rohn Cephas>
After discovering the HZB summer student program in LINKEDIN; I did immediately apply: Since that moment, my eyes were glued to my email to see if my application would bear the result. I was more than happy when I was listed among the International Summer School Students 2024 followed by the VIPERLAB project. In HZB, I am working on a project on perovskite solar cells which I could barely do in my home country Kenya due to the unavailable conditions required for their fabrication: A clean room and an inert environment are nothing to even imagine in the labs I was working back in my country. However, the unavailability of these conditions enables creativity: We are trying to improvise similar apparatus and materials in our labs since science cannot be learned without practical hands on experience. On the negative side, some of these conditions are really difficult to improvise.
Forward acceleration
As a young researcher from Kenya, I had an opportunity to carry out research project in the well-equipped laboratories in HZB and to interact not only with renowned researchers from Germany but also worldwide researchers. This has sharpened my research capability and increased my knowledge about science. It would be a great lie to say I only sharpened my skills but I also obtained new modern skills and knowledge. The interaction has created a much greater love for research and inspiration in the field of science. The force build in me has created a forward acceleration and since there is no external force that can stop me, I will continue in that state of forward motion in accordance to Newtons first law of motion.
My motivation
My interest in renewable energies has been driven by recent climatic change which has adversely affected humankind, plants, and animals. Renewable energies have to be placed at the center of research since it is a necessity for sustainable industrial development. This is further stated by SDG 7 of the United Nations. Solar energy is everywhere, is easy to maintain, can create jobs locally, is clean, and remains green forever. My country Kenya is located along the equator; thus, experiencing almost equal length of day and night with the dominance of sunshine during the day, throughout the year. This is an important resource which can be harnessed for our benefit. Furthermore, tsolar energy can be combined with agriculture, which we passionately practice in our home and is my parents’ source of income.
New generations of solar cells with perovskites
The photovoltaic developments are broadly grouped in four generations with a lot of technological developments. In recent days, perovskite solar cells have drawn a lot of attention due to their high achievable power conversion efficiency. On the negative side, its stability is not yet good enough and has deterred its production to the local market. My research at HZB was the Synthesis and Characterization of Novel Materials for Perovskite Solar Cells. Generally, I was enhancing perovskite solar stability by doping the active and electron transport layers. I synthesized materials, and characterized them using X-ray diffraction, UV-Vis spectroscopy and scanning electron microscopy.
On application to solar cell device, admirable results were obtained. The main fabrication method I used was spin coating, a common method common for thin films. When a material’s solution is spun at high speed, the surface tension and centripetal forces acts on the solution making it to come together and thus creating a covering. The method is simple and easy to apply, it also gives high power conversion efficiency. The quality of the perovskite solar cells produced by this method is optimized by setting spin time, speed and acceleration during spin coating.
Good results in the end
My research yielded a good result and I thank HZB which has invested a huge amount of money and infrastructure for this research. I must similarly appreciate my supportive HZB supervisor, Dr Natalia Maticiuc who has not only inspired me during the session but was also helpful in the process of my lab work. Additionally, my gratitude goes to Miss Alejandra Florez who was also beside me during step-by-step lab operations and work.
HZB was an eye opener on research with excellence. I would love to continue my research at HZB for my future projects including my PhD
On Rohn Cephas: Rohn graduated with Bachelor of Science in Physics and currently works on his master of science in Physics at Egerton University, Kenya. Although closely related, his project in his native institute is different from his ISSP-Project on “Synthesis and Characterization of Novel Materials for Perovskite solar Cells” under the supervision of Prof, Dr. Eva Unger and Dr. Natalia Maticuic at IRIS, Center of the Science.