Periodic Reporting for period 4 - 3D-FNPWriting (Unprecedented spatial control of porosity and functionality in nanoporous membranes through 3D printing and microscopy for polymer writing)
Reporting period: 2024-01-01 to 2024-12-31
Nature is able to design transport across membranes selectivity, gated in time, and with a direction, This is a key factor for our life. This performance remains unreached in technological pores and membranes. Thereby, transport through nanopores is relevant in numerous technologies such as catalysis, pollutant monitoring, energy conversion, or separation, recycling, and water treatment. Thus, nanoporous material and membrane- and with this nanopore transport design is one essential aspect for a more sustainable future including new smart industry and sustainable material concepts such as closed water circles and recycling.
To enable advanced transport control beyond the well-established size exclusion, precision in technological nanopore design needs to be improved. Thus, we need to push the limits of control on structure and functionalization in nanoscale porous materials and membranes. Furthermore, we need to understand the correlation between nanoscale structural and functional nanopore design and resulting transport or separation performance. This understanding is expected to enable, to date, technically unachieved transport control. To do so fundamental challenges in material synthesis and characterization have to be addressed.
To approach this goal 3D-FNPWriting developed a technology platform allowing automated porous material design with structural and functional control from the nanometer- to the macroscopic length scale. This is based on light-based 3D-printing of in-situ functionalized mesoporous material architectures as well as on local polymer writing into mesoporous films adapting high resolution microscopy techniques to induce photoreactions and especially photopolymerization down to the nanoscale. Based on this fundamental research 3D-FNPWriting provided the technology platform, new porous materials, as well as fundamental understanding on transport design strategies which may become relevant in future technologies such as recycling or adaptable material design.
To enable advanced transport control beyond the well-established size exclusion, precision in technological nanopore design needs to be improved. Thus, we need to push the limits of control on structure and functionalization in nanoscale porous materials and membranes. Furthermore, we need to understand the correlation between nanoscale structural and functional nanopore design and resulting transport or separation performance. This understanding is expected to enable, to date, technically unachieved transport control. To do so fundamental challenges in material synthesis and characterization have to be addressed.
To approach this goal 3D-FNPWriting developed a technology platform allowing automated porous material design with structural and functional control from the nanometer- to the macroscopic length scale. This is based on light-based 3D-printing of in-situ functionalized mesoporous material architectures as well as on local polymer writing into mesoporous films adapting high resolution microscopy techniques to induce photoreactions and especially photopolymerization down to the nanoscale. Based on this fundamental research 3D-FNPWriting provided the technology platform, new porous materials, as well as fundamental understanding on transport design strategies which may become relevant in future technologies such as recycling or adaptable material design.
We successfully implemented the proposed technology platforms on mesoporous silica 3D printing. This included the in-situ functionalization of the nanoscale pores by developing functional block-copolymer templates which control transport through nanopores and which can be integrated into the printing process. Furthermore, we implemented the proposed technology platform on automated, local polymer writing into nanoporous materials. To do so we screened visible-light induced polymerizations, selected suitable reaction mechanisms and optimized these towards polymerization in porous materials and under automated writing conditions. To characterize local polymer writing we worked on high resolution characterization. For example, we integrated a fluorescence dye into the written copolymer and validated that the fluorescence intensity correlates with polymer amount allowing to track local polymerization with high-resolution fluorescence microscopy. We implemented and validated characterization techniques for transport control including the application of impedance spectroscopy to mesoporous thin films as well as the application of FRAP to detection of molecule diffusion in mesoporous films.
In summary, 3D-FNPWriting pushed research on nanoporous material fabrication precision and related transport properties of nanopores. Thereby, two technology platforms on 3Dprinting, and on microscopy-based polymer writing were successfully established. This included reliable synthesis protocols, and visble-light based chemistry suitable for these technology platform of light-based 3D printing and nanoscale polymer writing. Mesoporous materials with precisely adjustable structural and functional hierarchy from the nano- to the macroscale were fabricated. Based on this light-based chemistry and this technology platform we developed exciting, before experimentally inaccessible, in-situ functionalized 3D-printed mesoporous ceramic materials as well as mesoporous films with nanoscopically placed functional polymers using surface plasmons as light source to initiate photopolymerizations. With this we provided the first example of 3D printed fully mesoporous as well as in-situ functionalized ceramic materials using DLP. Furthermore, 3D-FNPWriting advanced the understanding of transport control regarding ligand binding and the influence of multifunctional templates on stimuli-triggered transport gating. Finally, the first example of visible-light induced PET-RAFT in the restricted space (confinement) of nanoscale pores was demonstrated and subsequently successfully transferred to automated and locally resolved polymer writing.