Wet chemistry nanoarchitectonics for nanocrystal-based films

Abstract

Just as nanotechnology has provided a guiding framework for exploring phenomena at the nanoscale, the concept of nanoarchitectonics united and highlighted interdisciplinary approaches for constructing functional materials from basic nano-units such as atoms, molecules, and nanomaterials with precise nanoscale control. Within this context, a variety of nanoarchitectonic approaches were developed to achieve thin films structured at the nanoscale to offer tailored surfaces for applications. This review showcases the unique features and implications of wet-processed thin films of nanocrystals, spanning from assembly techniques to applications. Assembly methods include affordable and scalable adsorption approaches (i) such as the Langmuir–Blodgett (LB) method, layer-by-layer (LbL) assembly, spin coating, automated one-drop assembly, and spontaneous self-assembly. Electrochemical deposition approaches (ii) are also described since they offer a complementary route for spatially specific thin film deposition and for designing electrochemical devices. Both adsorption and electrochemistry-based approaches have utilized a wide variety of pre-formed nanocrystals (e.g. nanoparticles, two-dimensional materials, perovskites, nanocellulose…) with a 0D, 1D or 2D dimension. Yet, ionic precursors were also used, enabling the formation of nanocrystals in situ (iii). These strategies gave access to advanced surface architectures (nanosheets, hierarchical films, mesoporous and twisted structures) enabling highly sensitive sensors, ultrathin catalysts, electromagnetic interference shielding, structurally colored cellulose films, electrocatalytic water oxidation, functional electrodes and asymmetric solid-state devices. In particular, this review highlights recent examples of functional crystal films with chiral properties using circular dichroism and circularly polarized luminescence for sensing, optoelectronics, and smart materials. Future directions and opportunities in wet chemistry nanoarchitectonics for nanocrystal-based films include external process coupling, machine learning integration, and industrial-scale production.