The controlled fabrication of nanometer-scale objects is without doubt one of the central issues in current science and technology. However, existing fabrication techniques suffer from several disadvantages including size-restrictions and a general paucity of applicable materials. Because of this, the development of alternative approaches based on supramolecular self-assembly processes is anticipated as a breakthrough methodology. This review article aims to comprehensively summarize the salient aspects of self-assembly through the introduction of the recent challenges and breakthroughs in three categories: (i) types of self-assembly in bulk media; (ii) types of components for self-assembly in bulk media; and (iii) self-assembly at interfaces.

includes self-assembled fullerene crystals design from zero-to-higher dimensions, mesoporous fullerene crystals and their conversion into graphitic mesoporous carbons, high surface area nanoporous carbon material design from agro-waste for electrochemical supercapacitors and VOC adsorption. Somobrata AcharyaSomobrata Acharya received his Ph.D. degree from Jadavpur University, India. He is currently Associate Professor in the Centre for Advanced Materials (CAM), Indian Association for the Cultivation of Science (IACS), India. He is carrying out research in interdisciplinary areas probing structure-property relationship and possible applications of semiconductor nanomaterials in the areas of energy generation and consumption. His research area includes heterostructures, 2D nanostructures, superlattices, supramolecular assemblies and their suitable applications. Katsuhiko ArigaKatsuhiko Ariga received his Ph.D. degree from Tokyo Institute of Technology. He is currently the Director of Supermolecules Group and Principal Investigator of World Premier International (WPI) Research Centre for Materials Nanoarchitectonics (MANA), the National Institute for Materials Science (NIMS). His research is oriented to supramolecular chemistry, surface science, and functional nanomaterials (Langmuir-Blodgett film, layer-by-layer assembly, self-organized materials, sensing and drug delivery, molecular recognition, mesoporous material, etc. and he is now trying to combine them into a unified field. AbstractDesigning nanoscale components and units into functional defined systems and materials has recently received attention as a nanoarchitectonics approach. In particular, exploration of nanoarchitectonics in two-dimensions (2D) has made great progress these days. Basically, 2D nanomaterials are a center of interest owing to the large surface areas suitable for a variety of surface active applications. The increasing demands for alternative energy generation have significantly promoted the rational design and fabrication of a variety of 2D nanomaterials since the discovery of graphene. In 2D nanomaterials, the charge carriers are confined along the thickness while being allowed to move along the plane. Owing to the large planar area, 2D nanomaterials are highly sensitive to external stimuli, a characteristic suitable for a variety of surface active applications including electrochemistry. Because of the unique

Zinc selenide is an important wide-bandgap (2.8 eV) material [1] with a broad range of potential applications. It exhibits interesting photophysical phenomena involving green-blue light emission and high transmission in the infrared and the visible electromagnetic spectrum.[2] Nanoparticles of ZnSe, via quantum confinement, shape, size and surface dependent effects, hold promise for tuning the optical properties and for assembling the particles in nanoscale structures. ZnSe has been studied to a lesser extent compared with its 'closest of kin', CdS, CdSe, and ZnS nanoparticles. Spherical ZnSe particles have been produced and studied by several groups. [3][4][5] ZnSe shapes other than spheres have been synthesized and studied to a more limited extent. Several pioneering reports [6][7][8][9][10][11] have described various synthetic routes to produce ZnSe nanowires, and focus on their structural characterization and, occasionally, on their photoluminescence (PL) properties. The nanowires were typically ∼ 10-100 nm wide and several micrometers long. The narrowest reported ZnSe wires were 3-5 nm wide (with an average diameter of 19 nm) [7] and 5-50 nm wide.[8] Except for these narrowest of wires, all the other reported wires are wider than the Bohr diameter of (bulk) ZnSe (9 or 11.4 nm), [12] which limits the expected quantum confinement effects. We have found only one recent allusion to the production of ZnSe nanorods. [13] In a few cases, authors have used the term 'nanorods' for wide ZnSe particles with dimensions of 40-70 nm × 1.5-3 lm, [9] 50-100 nm × 5-15 lm, [10] and 16-20 nm × 120-279 nm, [11] all with relatively large aspect ratios. Here, both of the major dimensions of the particles are larger than the Bohr radius, and quantum confinement effects are expected to be very limited.In this communication, we report the production of uniform wurtzite ZnSe ultranarrow width (1.3 nm), 4.5 nm long nanorods, and 100-200 nm long nanowires with the same width, their characterization and their spectroscopic properties. The development of rods from more spherical nuclei is illustrated. Quantum-confinement effects are manifested in the light absorption and the PL of the particles. The narrow width, ∼ 1 nm, is reflected in the Raman spectrum. The uniformity of the rods and the wires is demonstrated by their spontaneous assembly into highly ordered two-dimensional (2D) supercrystals. This high uniformity and order, together with an intrinsic chemical bipolarity of the rods, is responsible for their one-dimensional growth and for the various unique, essentially one-dimensional processes they undergo, as well as for the polarization properties of their spectra.The synthesis makes use of ligating solvents, i.e., long-chain alkylamines, which enable a low temperature, one step, bench-top reaction of the relatively innocuous zinc acetate and selenourea precursors, to produce wurtzite ZnSe nanorods and nanowires. The nanorods and nanowires are of a uniform width and the nanorods are of a uniform length. The relative amount of r...

Materials and their assemblies of dimensions down to a few nanometers have attracted considerable scientific interest in physical, chemical, and biological sciences because of unique properties not available in their bulk counterparts. The Langmuir–Blodgett (LB) technique allows rigid nanomaterials to be aligned in particular structures through a flexible assembly process at liquid interfaces. In this review, we summarize the development of assembly of hard nanomaterials using soft LB techniques. An initial summary of the basic features of nanomaterials will include dimension‐related effects, synthesis, characterization, and analysis, and will be followed by examples of LB assemblies of nanomaterials described according to their morphology: nanoparticles, nanorods, nanowires, nanotubes, and nanosheets. Some of the nanomaterials have been fabricated in orientation‐controlled morphologies, and have been incorporated into prototype devices for gas sensing and photocurrent transport. In the final part of this review, the challenges remaining for LB techniques of hard nanomaterials will be overviewed, and will include a comparison with the widely‐used LB technique involving soft materials.

All-inorganic perovskite nanocrystals are emergent alternative of organolead halide perovskites. Cesium antimony halide (Cs3Sb2X9, X = Cl, Br, I) all-inorganic perovskites nanocrystals possessing analogous electronic configuration to the organolead halide perovskites are promising materials for optoelectronic applications. We report on a colloidal route to synthesis uniform Cs3Sb2Cl9 perovskite nanowires with lengths up to several microns. We have synthesized aspect ratio controlled nanorods with the same ∼20 nm diameter of nanowires by tuning the precursors and ligands in the reaction. The crystallinity of the nanocrystals is significantly altered from the pristine bulk trigonal and orthorhombic phases owing to the one-dimensional shape of the nanocrystals. Rietveld refinement carefully separates out orthorhombic phase from the trigonal phase revealing a coexistence of both the phases in a minor and major ratio in the nanocrystals. The functionality in the form of fast photodetector demonstrates Cs3Sb2Cl9 nanocrystals as promising materials for optoelectronic applications.