With nanoparticles from Nairobi to Berlin
preparing the samples for the analysis of metal nanoparticles. © private
In April, Nancy Ochiba was a guest at HZB in Berlin doing research on nanoparticles. “I made good use of the time,” says the young chemist from Nairobi, Kenya. First she took part in the Photon School for young scientists, then she joined the lab at the Institute for Solar Fuels as a guest researcher. “Here I can benefit from technology that is not available to me at the Kenya University of Technology. For example, I have now examined my samples under a scanning electron microscope.”
Research for a better future
Nancy is in the first year of her PhD. What motivates her? She wants to help people live better. “Currently, about 75% of households in Kenya still cook with firewood or paraffin,” Nancy says. “However, the smoke is unhealthy, and many women and children suffer from respiratory diseases.” Moreover, wood is hard to find and paraffin is expensive, apart from the climate-damaging effect of burning fossil resources.
Nancy is therefore investigating special catalysts to electrochemically produce a “green” fuel from CO2 and solar energy, such as methane or propane. The idea sounds appealing: the climate-damaging greenhouse gas CO2, which is produced when oil, gas or coal is burned, could be recycled into a new fuel. But the process is complex: the reaction of CO2 with water in an electrolyser requires energy, which in principle can be supplied by the sun – and special catalysts that ensure that the desired compounds are formed from water and CO2. The energy balance of these reactions is currently not yet convincing. But many processes would benefit from the development of suitable catalysts.
Catalyst research at BESSY
Nancy synthesises nanoparticles of two different metals, copper-nickel, copper-zinc or even copper-cobalt. These metal nanoparticles have very large surface areas which, depending on their nature, accelerate the desired chemical reactions. “It’s still pretty basic research,” says Nancy. But it’s important to take the first steps; these catalysts are very versatile.
Nancy will also be attending to the user meeting in June 2023. “I want to apply for beam time at BESSY II for operando studies of my nanoparticles, so I can see how they favor specific chemical reactions.” When Nancy is not working in the lab, she enjoys walking around Berlin: “I especially like the old sites of the city,” she says. “And that special sausage, the one with the sauce, I think it’s called currywurst.”
This blogpost is part of a series on our cooperation with scientists from Kenya.
Antonia Rötger
https://www.helmholtz-berlin.de/pubbin/news_seite?nid=33706;sprache=en
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