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[Display omitted] • Self-assembly of TiO 2 microstructures with spherical/hollow shapes. • Impact of TiO 2 microstructures on photovoltaic properties with α-Quaterthiophene. • Optical analysis using absorption spectroscopy and fluorescence emission. • Analysis of relaxation and photon energy in TiO 2 /α-Quaterthiophene nanocomposites. In this study, we investigate the optical, photovoltaic, and structural properties of TiO 2 nanostructures produced by alcoholysis using various alcohols. An X-ray diffraction study highlights how the choice of alcohols affects the process by revealing variations and separation. The anatase phase is confirmed by Raman spectroscopy, which also sheds light on the effects of various alcohols. The granular nature of TiO 2 microstructures is demonstrated using scanning electron microscopy. We demonstrate how the size and shape of microstructures influence the band gap using absorption spectroscopy. Using fluorescence spectroscopy and Franck-Condon analysis, we investigated the performance of the α-Quaterthiophene + 40 % TiO 2 nanocomposite. Important parameters are then taken out of the analysis using the Franck-Condon technique. Studies on the photovoltaic performance of the α-Quaterthiophene + 40 % TiO 2 nanocomposite active layer show significant improvements in both open-circuit voltage and short-circuit current when TiO 2 nanostructures are incorporated. This demonstrates the enormous potential of TiO 2 nanostructures to improve solar cell applications' efficiency. Self-assembly fabrication of TiO 2 microspheres via the alcolysis process and their effect on exciton dissociation in hybrid systems is a topic of interest in materials science and nanotechnology. [ABSTRACT FROM AUTHOR]

Although microscopic techniques have been used to characterize transition metal dichalcogenides (TMDs), direct observation of charge carrier dynamics distribution in TMDs with diverse shapes remains unexplored. Herein, ultrafast pump–probe microscopy (UPPM) is employed to reveal the carrier dynamics distribution in molybdenum disulfide (MoS2) and tungsten disulfide (WS2) monolayer of four shapes: triangular (t‐MoS2), curved triangular (c‐MoS2), triangular (t‐WS2), and hexagonal (h‐WS2). Monitoring the photon transmission T at 1.55 eV after pumping with a photon energy of 3.1 eV, a negative ΔT/T occurs in t‐MoS2 and c‐MoS2, while a positive ΔT/T is detected in t‐WS2 and h‐WS2 after 3–7 ps time evolution. This distinctive behavior is attributed to deep/shallow defects below the conduction band minimum (CBM) in MoS2 and WS2. Spatial‐independent ΔT/T is observed in t‐MoS2 and t‐WS2, while the ΔT/T in c‐MoS2 has a rapid decay of photoexcited carriers at the vertices and curved edges. Additionally, a threefold symmetry of ΔT/T is revealed in h‐WS2, attributed to the dissimilar occupation of defect states near the h‐WS2 CBM. This work paves the way for examining charge carrier dynamics of various shapes of TMDs and provides a unique microscopic method for studying the charge carrier dynamics in emerging TMDs heterostructures.

Nanomaterials are becoming important materials in several fields and industries thanks to their very reduced size and shape-related features. Scientists think that nanoparticles and nanostructured materials originated during the Big Bang process from meteorites leading to the formation of the universe and Earth. Since 1990, the term nanotechnology became very popular due to advances in imaging technologies that paved the way to specific industrial applications. Currently, nanoparticles and nanostructured materials are synthesized on a large scale and are indispensable for many industries. This fact fosters and supports research in biochemistry, biophysics, and biochemical engineering applications. Recently, nanotechnology has been combined with other sciences to fabricate new forms of nanomaterials that could be used, for instance, for diagnostic tools, drug delivery systems, energy generation/storage, environmental remediation as well as agriculture and food processing. In contrast with traditional materials, specific features can be integrated into nanoparticles, nanostructures, and nanosystems by simply modifying their scale, shape, and composition. This article first summarizes the history of nanomaterials and nanotechnology. Followed by the progress that led to improved synthesis processes to produce different nanoparticles and nanostructures characterized by specific features. The content finally presents various origins and sources of nanomaterials, synthesis strategies, their toxicity, risks, regulations, and self-aggregation.

Nanomaterials are becoming important materials in several fields and industries thanks to their very reduced size and shape-related features. Scientists think that nanoparticles and nanostructured materials originated during the Big Bang process from meteorites leading to the formation of the universe and Earth. Since 1990, the term nanotechnology became very popular due to advances in imaging technologies that paved the way to specific industrial applications. Currently, nanoparticles and nanostructured materials are synthesized on a large scale and are indispensable for many industries. This fact fosters and supports research in biochemistry, biophysics, and biochemical engineering applications. Recently, nanotechnology has been combined with other sciences to fabricate new forms of nanomaterials that could be used, for instance, for diagnostic tools, drug delivery systems, energy generation/storage, environmental remediation as well as agriculture and food processing. In contrast with traditional materials, specific features can be integrated into nanoparticles, nanostructures, and nanosystems by simply modifying their scale, shape, and composition. This article first summarizes the history of nanomaterials and nanotechnology. Followed by the progress that led to improved synthesis processes to produce different nanoparticles and nanostructures characterized by specific features. The content finally presents various origins and sources of nanomaterials, synthesis strategies, their toxicity, risks, regulations, and self-aggregation. [ABSTRACT FROM AUTHOR]