Humboldt Fellow joins HZB for battery research
Dr. Wenxi Wang specialises in the design of organic electrodes for lithium-sulfur and zinc-ion batteries and investigates interactions between ions and active materials. © arö/HZB
Dr. Wenxi Wang is working in the team of Prof. Yan Lu as Humboldt Foundation postdoctoral fellow. He studied at the Southern University of Science and Technology in Shenzhen, China, and completed his doctorate at the King Abdullah University of Science and Technology in Saudi Arabia. He specialises in the precise design of organic electrodes for lithium-sulfur and zinc-ion batteries and the investigation of the interactions between ions and active materials.
"At Helmholtz-Zentrum Berlin I find excellent conditions to deepen my research," says Wenxi Wang. Prof. Yan Lu's group has extensive experience in the synthesis and characterisation of novel electrode materials and state-of-the-art infrastructures for battery research. In addition, the X-ray source BESSY II at HZB offers a variety of spectroscopic methods to analyse electrochemical reactions in real time.
Lithium-sulfur (Li-S) batteries are considered one of the most interesting technologies to replace lithium-ion batteries due to their extremely high energy density and cheap starting materials. However, their performance still falls far short of expectations due, in part due to polysulfide intermediates that form during charging cycles. Porous host materials can trap such polysulfides, improving the energy density and lifetime of Li-S batteries. "My research project focuses on the precise design of organic-based host materials with suitable pore sizes and functional groups (Covalent Organic Frameworks, COF) to enable high-performance Li-S batteries and deepen our understanding of their mechanisms," says Wang.
- CIGS-perovskite tandem cell achieves record efficiency of 25.5 %A Berlin-based team from HZB and Center for the Science of Materials Berlin (CSMB) at the Humboldt-Universität zu Berlin has set a new record for a tandem solar cell. Using a combination of a CIGS semiconductor layer and perovskite, along with several optimised intermediate layers, they were able to convert 25.5% of sunlight into electrical energy. The previous record for this combination of materials and this size of cell stood at 24.6%. The new record has been certified and is visible in the prestigious Solar Cell Efficiency Tables (the "Green Tables"), which serve as the definitive ledger for the global photovoltaic community.
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- Perovskite solar cells: Predictions of long-term stabilityReliable statements about the long-term stability of perovskite solar cells are still difficult to make. However, a new study by Dr Carolin Ulbrich’s team, published in the renowned journal Joule, highlights which methods are useful for this purpose and identifies areas where further research is needed.