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DOE OSTI · 1838646

Kinetically Controlled Self-Assembly of Binary Polymer-Grafted Nanocrystals into Ordered Superstructures via Solvent Vapor Annealing

Wang, Yi·Chen, Jun·Zhu, Chenhui·Zhu, Baixu·Jeong, Soojin·Yi, Yi·Liu, Yang·Fiadorwu, Joshua·He, Peng·Ye, Xingchen
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Abstract

Polymer-inorganic nanocomposites based on polymer-grafted nanocrystals (PGNCs) are enabling technologically relevant applications owing to their unique physical, chemical, and mechanical properties. While diverse PGNC superstructures have been realized through evaporation-driven self-assembly, this approach presents multifaceted challenges in experimentally probing and controlling assembly kinetics. Here, we report a kinetically controlled assembly of binary superstructures from a homogeneous disordered PGNC mixture utilizing solvent vapor annealing (SVA). Using a NaZn 13 -type superstructure as a model system, we demonstrate that varying the solvent vapor pressure during SVA allows for exquisite control of the rate and extent of PGNC assembly, providing access to nearly complete kinetic pathways of binary PGNC crystallization. Characterization of kinetically arrested intermediates reveals that assembly follows a multistep crystallization pathway involving spinodal-like preordering of PGNCs prior to NaZn 13 nucleation. Our work opens up new avenues for the synthesis of multicomponent PGNC superstructures exhibiting multifunctionalities and emergent properties through a thorough understanding of kinetic pathways.

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77 NANOSCIENCE AND NANOTECHNOLOGYcrystallizationkinetically controlled self-assemblykineticsnonclassical crystallizationpolymer-grafted nanocrystalsscanning electron microscopysolvent vapor annealingsolventssuperstructures

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Wang, Yi, Chen, Jun, Zhu, Chenhui, Zhu, Baixu, Jeong, Soojin, Yi, Yi, Liu, Yang, Fiadorwu, Joshua, He, Peng, Ye, Xingchen. 2021-06-08. Kinetically Controlled Self-Assembly of Binary Polymer-Grafted Nanocrystals into Ordered Superstructures via Solvent Vapor Annealing. https://doi.org/10.1021/acs.nanolett.1c00890

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