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Ion-conducting polymers (ICPs) are gaining interest in various scientific and technological fields. This review highlights advancements in ICP thin films using chemical vapor deposition (CVD) and addresses challenges of traditional methods. 

Abstract Initiated Chemical Vapor Deposition (iCVD) is a versatile and powerful technique for controlling the morphology of polymeric and hybrid thin films, with applications spanning from electronics to biomedical devices. This review highlights recent advancements in iCVD technology that enable precise morphological control from creating ultrasmooth films to self‐assembled nanostructures. Advances in reactor design now allow for in situ monitoring of key parameters, such as film thickness and surface imaging, providing real‐time insights into material morphology. Surface morphology is influenced by both the substrate and coating layer. For the former, iCVD offers significant advantages in creating defect‐free, conformal coatings over complex substrates, making it particularly well‐suited for flexible electronics, optical devices, and antifouling/antimicrobial biointerfaces. For the latter, iCVD has been leveraged for the fabrication of microstructured coatings that improve energy storage, gas sensing, and pathogen detection, superhydrophobic or anti‐icing surfaces. Its all‐dry processing and compatibility with temperature‐sensitive substrates further emphasize its potential for sustainable manufacturing. The ability to fine‐tune film chemistry and morphology, combined with the scalability, positions iCVD as a promising tool for addressing future technological challenges in advanced materials design. 

Abstract Nature‐inspired functional surfaces with micro‐ and nanoscale features have garnered interest for potential applications in optics, imaging, and sensing. Traditional fabrication methods, such as lithography and self‐assembly, face limitations in versatility, scalability, and morphology control. This study introduces an innovative technology, condensed droplet polymerization (CDP), for fabricating polymeric micro‐ and nano‐dome arrays (PDAs) with readily tunable geometric properties—a challenging feat for conventional methods. The CDP process leverages free‐radical polymerization in condensed monomer droplets, allowing rapid production of PDAs with targeted sizes, radii of curvature, and surface densities by manipulating a key synthesis parameter: the temperature of a filament array that activates initiators. This work systematically unravels its effects on polymerization kinetics, viscoelastic properties of the polymerizing droplets, and geometric characteristics of the PDAs. Utilizing in situ digital microscope, this work reveals the morphological evolution of the PDAs during the process. The resulting PDAs exhibit distinct optical properties, including magnification that enables high‐resolution imaging beyond the diffraction limit of conventional microscopes. This work demonstrates the ability to magnify and focus light, enhancing imaging of subwavelength structures and biological specimens. This work advances the understanding of polymerization mechanisms in nano‐sized reactors (i.e., droplets) and paves the way for developing compact optical imaging and sensing technologies. 

Green-processed conjugated materials can reduce the cost of optoelectronic devices and simultaneously minimize their ecological footprint. Here, we use both solution and vapor phase chemistry to oxidatively polymerize the natural hydrocarbon dye, guaiazulene, yielding the more functional material poly(guaiazulene). We chemically characterize oligomers of poly(guaiazulene) using nuclear magnetic resonance spectroscopy, gel-permeation chromatography, laser-desorption ionization mass spectroscopy, and ultraviolet-visible absorption spectroscopy. The optical properties of poly(guaiazulene) oligomers are studied via electronic structure calculations and are contrasted to those of standard poly(azulene). We show that poly(guaiazulene) films synthesized from the vapor phase exhibit enhanced optical properties compared to counterparts synthesized in solution. Collectively, this work outlines a green reaction process that consists of a single step and uses earth-abundant reagents to yield a hitherto unreported polymer for optoelectronic applications. 

Understanding how dipolar, non-centrosymmetric organic semiconductors self-assemble, nucleate, and crystallize is integral for designing new molecular solids with unique physical properties and light-matter interactions. However, dipole–dipole and van der Waals interactions compete to direct the assembly of these compounds, making it difficult to predict how solids are formed from individual molecules. Here, we investigate four small molecules ( TpCPD , TpDCF , AcCPD , and AcDCF ) possessing anisotropic, non-planar structures and large dipole moments, and establish robust algorithms to control their molecular self-assembly via simple physical vapor deposition. Each molecule contains a central polar moiety, consisting of either a cyclopentadienone (CPD, ca. 3.5 D dipole moment) or dicyanofulvene (DCF, ca. 7.0 D dipole moment) core, that is surrounded by either four twisted phenyl (Tp) groups or a fused aromatic (acenaphthene, Ac) ring system. We find that only molecules containing the fused ring system form 1D nanowires due to the stronger van der Waals associations of the long, planar acenaphthene moieties. We examine the kinetics of self-assembly for AcDCF and create diverse 1D morphologies, including both curved and linear nanostructures. Finally, using conductive AFM (c-AFM) measurements, we show that 1D AcDCF wires support higher current densities relative to randomly-oriented clusters lacking long-range order.