Welcome to the digital home of the Knebel Group. We are a multidisciplinary team working on fundamental molecular design, physicochemical characterizations and technical, industry relevant application. We are pushing the boundaries of how porous materials can solve the most pressing challenges in energy relevant climate change mitigation and resource efficient separations. By stimuli responses we try to mimic the biological membrane in a technical abstraction, using light-switching, thermal glass transition, breathing phenomena and electric field-controlled distortion to create controllable channels. We then use these phenomena, scale materials and methods up and transfer them into mostly CO2-related application cases.
- Inorganic Materials Chemistry: Pore Design in Reticular Materials with Stimuli Response
At the heart of our research is reticular chemistry. We don’t just find materials; we build them from the ground up. By using metal ions and organic “linkers,” we assemble highly ordered, porous frameworks such as Metal-Organic Frameworks (MOFs) and Covalent Organic Frameworks (COFs).
Our idea is to make external stimuli responsive MOFs and COFs for the desired task:Building designer materials the size, shape, and chemical environment of pores to target specific molecules. Moving beyond bulk powders, we specialize in nanosized powders, polymer composites and the growth of oriented thin films and 2D membranes through wet chemistry. Surface functionalization helps us to discover new material classes, such as “liquids with permanent porosity”, or make highly performant polymer-composite fillers through cross-linking between crystal and matrix.
- Physical Chemistry: Fundamentally Understand the Stimuli Responsive Materials
Synthesizing a material is only half the challenge: understanding how ions and functional moieties behave within the porous architectures is where fundamental phenomenon are characterized. We employ advanced spectroscopic and analytical techniques to study the thermodynamics and kinetics of interfaces.
With physciochemical methods we investigate the kinetics of diffusion in stimuli responsive reticular materials: Our smart designer materials change their structure or properties in response to external physical triggers. We use a plethora of different characterization methods to track gases, ions and molecules in-situ. We investigate processes under operating conditions to watch and decipher these phenomena.
- Material Science and Technical Chemistry
Research is only as good as its impact. As a crucial part of our research, we translate molecular insights and phenomena in scalable materials platforms for real-world applications in gas sensing and separation. Our artificial membranes are used to develop advanced separation processes with controllable molecular sieving ability or stimuli responses are used to detect gases. With membrane separation processes in Wicke-Kallenbach geometry, we investigate how MOF-membrane thin films help us to decarbonize the chemical industry and capture CO2 from the industry fumes.
With synthetic upscale of reticular materials, the use of 3D-printing and experiments for machine learning we develop a scalable platform: Mixed-Matrix Membranes (MMMs) incorporate custom-designed MOFs in custom-designed polymer matrices. Polycrystalline and glassy reticular materials help to develop separation and sensing technology of tomorrow. Improving membranes to break the upper bound of permeability and selectivity and replace energy intensive processes disruptively with novel materials in the chemical industry is our goal.
We recieve funding from:
Breakthroughs
SPP 1928/2
GRK 3014 PhInt
2021FGR 0040 (MMMs) & 2025FGR 0089 (RespoBrane)