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Nickel titanate (NiTiO3) nanostructured materials have gained extensive attention in the field of lithium‐ion batteries (LIBs) due to their high theoretical capacity and low cost. However, NiTiO3 exhibits low conductivity and significant volume changes during cycling, resulting in capacity decay and poor cycling stability. Herein, we propose a feasible strategy to enhance the cycling performance of NiTiO3 nanostructures by adjusting their morphology. By manipulating the choice of solvent employed in the synthetic process, we obtain NiTiO3 microbars (NTO MBs) through self‐assembly of NiTiO3 nanoparticles (NTO NPs). When utilized as an anode material in LIBs, NTO MBs exhibit a capacity of 410 mAh g−1 after 200 cycles at 100 mA g−1, surpassing that of NTO NPs (212 mAh g−1). The improved performance of NTO MBs is attributed to their unique porous bar‐like structure, composed of numerous NPs, which provides a substantial storage space for Li+ ions owing to its larger specific surface area. Additionally, the porous structure accelerates the diffusion of Li+ ions and electron transfer. To gain a profound understanding of the enhanced performance through morphology adjustment, we conduct a comprehensive investigation on the growth mechanism of NTO MBs. This work provides valuable insights into the mechanism governing the morphology control of NTO MBs, facilitating the rational design and synthesis of tailored materials with enhanced performance for LIBs. [ABSTRACT FROM AUTHOR]

All‐inorganic halide perovskites exhibit exceptional optical properties and are promising photoactive materials for optoelectronics. However, their stability remains a key challenge, exacerbated by a limited understanding of degradation mechanisms. Herein, in situ transmission electron microscopy (TEM) is used to investigate the effect of thickness on the structural stability of CsPbBr3 nanobricks under electron beam irradiation. CsPbBr3 nanobricks with different thicknesses have been prepared using a traditional hot‐injection method, giving rise to a distinctive cubic structure. A modulated structure, caused by bromine vacancy ordering, has been observed in the thin nanobricks. The degradation behaviors of nanobricks are related to thickness‐dependent bromine vacancy formation in the CsPbBr3 lattice. More bromine vacancies exist in thin nanobricks than thick ones, resulting in a greater number of undercoordinated Pb atoms which accelerate irradiation‐induced degradation. Decomposition products include Pb nanoparticles, which also demonstrate thickness‐dependent characteristics. TEM images of Pb nanoparticles formed from thin nanobricks show evidence of irradiation‐induced amorphization. In thicker nanobricks, Pb nanoparticle size increases with the duration of electron beam irradiation, while the remaining Cs atoms bond with Br atoms to form relatively stable CsBr nanoparticles. These results contribute to understanding of degradation mechanisms in cesium lead halide perovskites under electron beam irradiation. [ABSTRACT FROM AUTHOR]

Reward has been shown to influence selective attention, yet previous research has primarily focused on rewards associated with specific locations or features, with limited investigation into the impact of a reward object on object-based attention (OBA). Therefore, it remains unclear whether objects previously associated with rewards affect OBA. To address this issue, we conducted two experiments using a paradigm that combined a reward training phase with a modified two-rectangle paradigm. The results indicate that a reward object modulates both space-based attention (SBA) and OBA. When cues appear on a reward object, the effects of both SBA and OBA are amplified compared to when cues appear on a no-reward object. This finding supports the value-driven attentional capture (VDAC) theory, which suggests that a reward object gain enhanced saliency to capture attention, thereby providing a theoretical support for the treatment of conditions such as drug addiction. [ABSTRACT FROM AUTHOR]

Transition metal oxide (TMO) nanomaterials possess both novel nanoeffects and excellent semiconductor properties that make them promising materials for electronics and photonics. Great expectations have been placed on TMO nanomaterials to deal with the global challenges in many fields, especially portable equipment and energy issues. In the last decades, extensive research work concentrated on the synthesis, microstructure, and macro-performance of TMO nanomaterials. A comprehensive understanding of both growth mechanism and underlying relationship between microstructure and physical properties can lead to performance enhancements of TMO nanomaterials in electronics and photonics, which in turn enables the fabrication TMO nanostructures based on anticipated design strategies. At present, TMO nanostructures do not satisfactorily meet the technical criteria for direct practical applications in electronics and photonics. In this paper, recent developments in synthesis, characterization, and prominent applications of TMO nanomaterials are reviewed from a structural perspective, which serves as a stepping stone to develop novel nanostructures with superior performances and provides a necessary guidance for transformation of scientific achievements into practical applications. [ABSTRACT FROM AUTHOR]

The study assessed the role of an activated carbon nanoparticle lymphatic tracer in reducing unintentional damage to the parathyroid glands during thyroidectomy for papillary thyroid non-microcarcinoma diagnosed intraoperatively by cryosections. A total of 103 patients with papillary thyroid non-microcarcinomas diagnosed by intraoperative cryosection were randomly assigned to receive routine radical thyroidectomy or radical thyroidectomy following administration of activated carbon nanoparticle lymphatic tracer to the contralateral thyroid, at the department of Thyroid Surgery, Sun Yat-sen Memorial Hospital (Guangzhou, China), between January 2012 and May 2013. The success of level VI lymphadenectomy and postoperative parathyroid function were compared. Administration of the activated carbon nanoparticle lymphatic tracer did not affect the frequency of recovered lymph nodes containing metastases; however, it did significantly reduce the incidence of permanent and transient hypoparathyroidism from 2 to 0 and 18 to 6, and reduced the mean recovery time for transient hypoparathyroidism from 57.0 days to 22.3 days. Administration of activated carbon nanoparticles to the contralateral thyroid after intraoperative cryosections did not contribute to lymphadenectomy for papillary thyroid non-microcarcinoma, but significantly protected parathyroid functions. This approach could decrease the morbidity of radical thyroidectomy and the occurrence of hypoparathyroidism. [ABSTRACT FROM AUTHOR]

The photocatalytic mechanism of a Cu2O/CuO hybrid system is disclosed in detail by density functional theory (DFT) calculations. The synergistic relationship of the two counterparts is confirmed by hydrogen peroxide (H2O2) formation on the CuO nanowires and dissociation on the Cu2O nanoparticles; this enables the system to self-sufficiently produce hydroxyl radicals, which is highly efficient in the photocatalytic degradation of methyl orange. The exposed surfaces are found to be crucial in the cooperative photocatalytic system, especially the Cu2O(111) surface, in the dissociation of H2O2. The distinct positions of the conduction band minimum and valence band maximum for CuO and Cu2O and synergic surface reactions enable the effective utilization of the electrons and holes generated by visible-light irradiation. Our results will contribute to a greater understanding of the specific mechanism of photodegradation catalyzed by Cu2O/CuO heterostructures, which may lead to promising directions in structure optimization for photocatalysts with high photocatalytic efficiency. [ABSTRACT FROM AUTHOR]

Novel hybrid nanocomposites of Cu2O nanoparticles (NPs) partially embedded in CuO nanowires (NWs) were produced by simple thermal reduction of CuO NWs in a vacuum. It is found that most Cu2O NPs adopt two regular shapes, one being cubic and the other being octahedral. The shape selection of the Cu2O nanocrystals is governed by the orientation relationship between Cu2O NPs and CuO NWs. The formation of such hierarchical hybrid nanostructures is induced by the topotactic reduction of CuO NWs. Compared with pure CuO NWs, the polyhedral Cu2O NP–CuO NW hierarchical hybrid nanostructures exhibit enhanced ability to photodegrade methyl orange under visible light, which is attributed to the synergic effects of CuO NWs and Cu2O NPs. [ABSTRACT FROM AUTHOR]

Compared to the high-temperature hot injection (HI) technique, the room-temperature supersaturated recrystallization (SR) approach is more hopeful to realize the industrialized production of CsPbX 3 (X = Cl, Br, and I) nanomaterials. However, accurate compositional control of the product is still difficult, and the role and underlying mechanism of antisolvents in the reprecipitation process remain unclear. Herein, CsPbBr 3 particles and CsPbBr 3 /Cs 4 PbBr 6 composites with certain proportions are synthesized using different antisolvents with the SR method. By adjustment of the polarity or functional group of antisolvents, it is found that the functional groups of antisolvents have a major impact on the composition of the products. Furthermore, the influential mechanism of different antisolvents on the compositions of products is investigated by combining electrostatic potential calculations and ultraviolet-visible absorption spectroscopy. It suggests that the interaction between functional groups of antisolvents and organic ligands influences the coordination status of the intermediate Pb-complex and further affects the separating rate of the Pb(II)-intermediate, leading to the formation of products with different compositions. A physicochemical mechanism is proposed to explain the formation of Cs 4 PbBr 6 and CsPbBr 3 . This work deepens the understanding of the formation mechanism of all-inorganic metal halide perovskite-related materials based on the SR method and provides new routes to achieve their controllable preparation.

All-inorganic metal halide perovskites have attracted considerable attention due to their high application potentials in optoelectronics, photonics, and energy conversion. Herein, two-dimensional (2D) CsPbBr 3 nanosheets with a thickness of about 3 nm have been synthesized through a simple chemical process based on a hot-injection technique. The lateral dimension of CsPbBr 3 nanosheets ranges from 11 to 110 nm, which can be tuned by adjusting the ratio of short ligands (octanoic acid and octylamine) over long ligands (oleic acid and oleylamine). The nanosheets result from the self-assembly of CsPbBr 3 nanocubes with an edge length of about 3 nm, which possess the same crystal orientation. In addition, an amorphous region of about 1 nm in width is found between adjacent nanocubes. To investigate both the structure and the growth mechanism of these nanosheets, microstructural characterizations at the atomic scale are conducted, combined with X-ray diffraction analysis, 1 H nuclear magnetic resonance ( 1 H NMR) measurement, and density functional theory (DFT) calculation, aiming to determine the configuration of different ligands adsorbed onto CsPbBr 3 . Our results suggest that the adjacent nanocubes are mainly connected together by short ligands and inclined long ligands. On the basis of the DFT calculation results, a relationship is derived for the volume ratio of short ligands over long ligands and the lateral dimensions of CsPbBr 3 nanosheets. Moreover, a physicochemical mechanism is proposed to explain the 2D growth of CsPbBr 3 nanosheets. Such a finding provides new insights regarding the well-ordered self-arrangement of CsPbBr 3 nanomaterials, as well as new routes to synthesize 2D CsPbX 3 (X = Cl and I) nanosheets of suitable dimensions for specific and large-scale applications.

The photocatalytic mechanism of a Cu 2 O/CuO hybrid system is disclosed in detail by density functional theory (DFT) calculations. The synergistic relationship of the two counterparts is confirmed by hydrogen peroxide (H 2 O 2 ) formation on the CuO nanowires and dissociation on the Cu 2 O nanoparticles; this enables the system to self-sufficiently produce hydroxyl radicals, which is highly efficient in the photocatalytic degradation of methyl orange. The exposed surfaces are found to be crucial in the cooperative photocatalytic system, especially the Cu 2 O(111) surface, in the dissociation of H 2 O 2 . The distinct positions of the conduction band minimum and valence band maximum for CuO and Cu 2 O and synergic surface reactions enable the effective utilization of the electrons and holes generated by visible-light irradiation. Our results will contribute to a greater understanding of the specific mechanism of photodegradation catalyzed by Cu 2 O/CuO heterostructures, which may lead to promising directions in structure optimization for photocatalysts with high photocatalytic efficiency.

Bicrystalline α-Fe2O3 nanoblades (NBs) synthesized by thermal oxidation of iron foils were reduced in vacuum, to study the effect of reduction treatment on microstructural changes and photocatalytic properties. After the vacuum reduction, most bicrystalline α-Fe2O3 NBs transform into single-layered NBs, which contain more defects such as oxygen vacancies, perfect dislocations and dense pores. By comparing the photodegradation capability of non-reduced and reduced α-Fe2O3 NBs over model dye rhodamine B (RhB) in the presence of hydrogen peroxide, we find that vacuum-reduction induced microstructural defects can significantly enhance the photocatalytic efficiency. Even after 10 cycles, the reduced α-Fe2O3 NBs still show a very high photocatalytic activity. Our results demonstrate that defect engineering is a powerful tool to enhance the photocatalytic performance of nanomaterials.