Sequential infiltration synthesis (SIS) is an emerging method for vapor-phase growth of inorganic materials within polymers that is utilized for hybrid organic–inorganic and inorganic nanostructure fabrication. The range of SIS applications has been continuously expanding for the past decade. A fundamental understanding of precursor–polymer interactions is, however, essential to expand the use of SIS to additional chemistries and move beyond thin film polymer templates. This work utilizes density functional theory (DFT) calculations and in situ gravimetric analysis to probe the growth mechanism of trimethyl­aluminum (TMA) within poly­(methyl methacrylate) (PMMA) and poly­(2-vinylpyridine) (P2VP). The theoretical and experimental analyses reveal that each precursor–polymer pair is characterized by a balance point temperature at which rates of forward and reverse precursor–polymer binding enable maximum mass gain at thermodynamic equilibrium. At short exposure times, mass gain is significantly influenced by the pressure profile of the process chamber. Mechanism comprehension enabled nanopatterning of a previously unsuitable block copolymer (BCP), polystyrene-block-P2VP (PS-b-P2VP), at elevated temperatures. It was proven possible to grow significant mass while maintaining the pattern by stabilizing the morphology via a single cycle at low-temperature SIS, thus overcoming self-assembly sensitivity to temperature.

Nanofabrication is continuously searching for new methodologies to fabricate 3D nanostructures with 3D control over their chemical composition. A new approach for heterostructure nanorod array fabrication through spatially controlled–growth of multiple metal oxides within block copolymer (BCP) templates is presented. Selective growth of metal oxides within the cylindrical polymer domains of polystyrene‐block‐poly methyl methacrylate is performed using sequential infiltration synthesis (SIS). Tuning the diffusion of trimethyl aluminum and diethyl zinc organometallic precursors in the BCP film directs the growth of AlOx and ZnO to different locations within the cylindrical BCP domains, in a single SIS process. BCP removal yields an AlOx‐ZnO heterostructure nanorods array, as corroborated by 3D characterization with scanning transmission electron microscopy (STEM) tomography and a combination of STEM and energy‐dispersive X‐ray spectroscopy tomography. The strategy presented here will open up new routes for complex 3D nanostructure fabrication.

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A novel combination of block copolymer (BCP) nano spray-drying (NSD), solvent annealing, and selective metal oxide growth is utilized to create functional polymer nanoparticles, polymer-metal-oxide hybrid nanoparticles, and templated metal oxide nanoparticles with tunable composition, internal morphology, and porosity. NSD of BCPs from chloroform and toluene solutions results in porous and nonporous nanoparticles, respectively, with various degrees of phase separation. Further tuning of the nanoparticle internal morphology is performed by solvent annealing the spray-dried particles with judicious choice of the nonsolvent dispersion medium and the surfactant, yielding assembly of both blocks at the surface of the nanoparticles. Finally, ZnO and Al 2 O 3 are grown inside the polar blocks of phase-ordered nanoparticles using a sequential infiltration synthesis method, in a post-assembly process, resulting in hybrid BCP-ZnO particles and BCP-templated Al 2 O 3 nanoparticles, as demonstrated by scanning transmission electron microscopy tomography. These structure engineering methods open new ways to direct and template functional nanoparticles.

Creating ultrathin films via ballistic impact-induced frictional material transfer could be a new approach for additive manufacturing compared with current solvent-assisted polymer coatings. The covalently bonded A block brushes and B block brushes are robust mechanical units in A/B lamellar diblock copolymers (BCPs). The parallel brush–brush interfaces with low entanglement density present a unique set of slip planes that can undergo extreme deformation by shearing and delamination by tensile forces. Impact of microspheres comprised of concentric glassy–rubbery brush layers against a rigid substrate at ballistic strain rates causes adiabatic shock heating that permits compressional thinning of the bottommost layers via slip over both types of BCP brushes. In cooler regions, the mechanical contrast between the glassy A blocks and rubbery B blocks induces extensive slip across the rubbery block brushes. For angled impacts, the increased shear stress enhances brush slip and the particle slides across the substrate accompanied by delamination across the slip planes and unique frictional transfer of discrete B-block-A A-block B layers.