Elucidating Synthetic Pathways in the Synthesis of Block Copolymer Self-Assembly Derived Mesostructured Nitrides with in situ Multimodal Synchrotron Characterization

Block copolymer-inorganic hybrid co-assembly has recently emerged as a scalable, tunable route to crystallographically ordered, mesoporous, highly crystalline inorganics relevant to catalysis, energy conversion and storage, and other areas. The successful synthesis of these materials, however, often relies on heavily tuned thermal processing in order to crystallize a functional inorganic material without crystal growth-induced mesostructure collapse. For example, in our recent efforts to produce gyroidal niobium nitride (NbN) superconductors, a two-step thermal treatment process was needed with temperature sensitivity ca. ± 1%. To enable the rapid discovery and optimization of these synthesis routes, we developed an in situapparatus capable of measuring small- and wide- angle x-ray scattering (SAXS/WAXS) during annealing at temperatures up to 1200 C in reactive gases. In a first application, we have explored the transformation pathways from block copolymer-oxide nanocomposite to nitride, resulting in the first synthesis of a mesostructured nitride from a Pluronics ABA block copolymer. We expect that this system will enable the rapid screening of a variety of block copolymer-derived oxide, nitride, and carbide materials with applications in catalysis, energy, and beyond.