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1.
BMC Musculoskelet Disord ; 24(1): 43, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36653778

RESUMO

PURPOSE: When it comes to treating lumbar spinal stenosis (LSS), a procedure known as microscope-assisted fenestration decompression has expediently become the gold standard. With the advancement of spinal endoscopy, the Delta large-channel approach has shown promising clinical outcomes in the management of lumbar spinal stenosis. However, case studies of this method being used to treat lumbar spinal stenosis are still uncommon. The purpose of this research was to examine how well microscopy-assisted laminectomy and the Delta large-channel approach work in treating LSS in the clinic. METHODS: From May 2018 to June 2020, 149 patients diagnosed with LSS were divided into 80 patients in Delta large-channel technique groups (FE group) and 69 patients in microscope groups (Micro group). Lower back and lower limb pain were measured using the visual analogue scale (VAS-LBP and VAS-LP), while lower limb numbness was evaluated using the 11-point numerical rating scale (NRS-LN); modified Oswestry Disability Index (ODI) was used to evaluate the quality of life, and modified MacNab criteria were used to assess the clinical efficacy before surgery and at one week, three months, six months, and 12 months after surgery. All patients had single-level lumbar spinal stenosis, and clinical data such as hospital stay, operation time, intraoperative blood loss were statistically analyzed. RESULTS: Finally, 111 patients (62 in FE group and 49 in Micro group) completed follow-up. Compared with preoperative results, postoperative VAS-LBP, VAS-LP, NRS-LN score and modified ODI score were significantly improved in 2 groups (P < 0.05), but there was no significant difference in postoperative follow-up at each time point (P > 0.05), Except 1 week after surgery, VAS-LBP in FE group was lower than that in Micro group (P < 0.05). It is noteworthy that the FE group had a shorter hospital stay, less intraoperative blood loss, and a quicker time of getting out of bed when compared with the microscope group,but the operation time was just the opposite (P < 0.05). The excellent and good rate was 83.87% in FE group and 85.71% in Micro group (P > 0.05). CONCLUSIONS: Both microscope-assisted laminar fenestration decompression and Delta large-channel procedures provide satisfactory treatment outcomes, however the Delta large-channel approach has some potential advantages for the treatment of LSS, including quicker recovery and sooner reduced VAS-LBP. Long-term consequences, however, will necessitate additional follow-up and research.


Assuntos
Estenose Espinal , Humanos , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/cirurgia , Descompressão Cirúrgica/métodos , Perda Sanguínea Cirúrgica , Microscopia , Estudos Prospectivos , Qualidade de Vida , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Endoscopia/métodos , Resultado do Tratamento , Estudos Retrospectivos
2.
Soft Matter ; 18(46): 8840-8849, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36373235

RESUMO

We investigate three azo-chromophore-containing photoswitches (1, 2 and 3) for molecular solar thermal storage (MOST) based on reversible Z-E isomerization. 1, 2 and 3 are photoswitchable compounds that contain one, two and three azo chromophores, respectively. In solution, 1, 2 and 3 were charged via UV-light-induced E-to-Z isomerization. Among these three compounds, 2 exhibited an energy density as high as 272 ± 1.8 J g-1, which showed the best energy storage performance. This result originated from the low molecular weight, a high degree of photoisomerization, and moderate steric hindrance of 2, which demonstrated the advantages of the meta-bisazobenzene structure for MOST. In addition, we studied the performances of these photoswitches in the solvent-free state. Only 1 showed photoinduced reversible solid-to-liquid transitions, which enabled the charging of 1 in a solvent-free state. The stored energy density for 1 in a solvent-free state was 237 ± 1.5 J g-1. By contrast, 2 and 3 could not be charged in the solvent-free state due to the lack of solid-state photoisomerization. Our findings provide a better understanding of the structure-performance relationship for azobenzenebased MOST and pave the way for the development of high-density solar thermal fuels.

3.
Angew Chem Int Ed Engl ; 58(29): 9712-9740, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30737869

RESUMO

Heating and cooling can induce reversible solid-to-liquid transitions of matter. In contrast, athermal photochemical processes can induce reversible solid-to-liquid transitions of some newly developed azobenzene compounds. Azobenzene is photoswitchable. UV light induces trans-to-cis isomerization; visible light or heat induces cis-to-trans isomerization. Trans and cis isomers usually have different melting points (Tm ) or glass transition temperatures (Tg ). If Tm or Tg of an azobenzene compound in trans and cis forms are above and below room temperature, respectively, light may induce reversible solid-to-liquid transitions. In this Review, we introduce azobenzene compounds that exhibit photoinduced reversible solid-to-liquid transitions, discuss the mechanisms and design principles, and show their potential applications in healable coatings, adhesives, transfer printing, lithography, actuators, fuels, and gas separation. Finally, we discuss remaining challenges in this field.

4.
Analyst ; 140(15): 5205-15, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26057132

RESUMO

Inspired by a sequential hydrolysis-precipitation mechanism, morphology-controllable hierarchical cupric oxide (CuO) nanostructures are facilely fabricated by a green water/ethanol solution-phase transformation of Cu(x)(OH)(2x-2)(SO4) precursors in the absence of any organic capping agents and without annealing treatment in air. Antlerite Cu3(OH)4(SO4) precursors formed in a low volume ratio between water and ethanol can transform into a two-dimensional (2D) hierarchical nanoporous CuO ribbon assembly of free-standing nanoneedle building blocks and hierarchical nanoneedle-aggregated CuO flowers. Brochantite Cu4(OH)6(SO4) precursors formed in a high volume ratio between water and ethanol can transform into hierarchical nanoplate-aggregated CuO nanoribbons and nanoflowers. Such 2D hierarchical nanoporous CuO ribbons serving as a promising electrode material for nonenzymatic glucose detection show high sensitivity, a low detection limit, fast amperometric response and good selectivity. Significantly, this green water-induced precursor-hydrolysis method might be used to control effectively the growth of other metal oxide micro-/nanostructures.


Assuntos
Cobre/química , Nanoestruturas/química , Técnicas Biossensoriais , Técnicas Eletroquímicas , Eletrodos , Glucose , Modelos Moleculares , Nanoestruturas/ultraestrutura , Nanotecnologia , Porosidade
5.
Phys Chem Chem Phys ; 17(44): 29479-82, 2015 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-26486757

RESUMO

Novel etched Cu2O cubes with exposed {110} facets are synthesized via an oxidative etching method at room temperature. The photocatalytic performance indicates that these architectures show higher photocatalytic activity than that of the normal Cu2O cubes in the degradation of methylene orange.

6.
Phys Chem Chem Phys ; 16(35): 18918-25, 2014 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-25084025

RESUMO

Morphology is a primary part of designing metal nanocrystals and nanomaterials with controlled functional properties. Here, we demonstrate the potential of foreign sulfate ions to tune the silver dendrites to highly branched chains through a simple galvanic replacement reaction without introducing any organic surfactants. We further illustrate the underlying mechanism according to diffusion-limited aggregation (DLA) in the presence of sulfate ions. The special aspects of this simple synthetic strategy are the control of both the nucleation process and the subsequent crystal growth stage by using sulfate ions as the ionic surfactants thereby tuning the total surface energies on various crystal facets in solution and transforming crystal growth habits of the products. Moreover, the highly branched silver chains (HBSCs) with pure surfaces have been successfully employed as a Raman probe for surface-enhanced Raman spectroscopic analysis of rhodamine 6G (R6G). The particular morphology of those HBSCs also makes them find potential applications in biosensing, catalysis and optics.

7.
Phys Chem Chem Phys ; 16(38): 20424-8, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25166218

RESUMO

For the first time, one-pot solution-phase selective-etching to create cuboctahedral Cu2O crystals enclosed by both stepped {111} surfaces and smooth {100} surfaces has been demonstrated. Investigation of photocatalytic performances indicates that the stepped cuboctahedral Cu2O crystals have higher photocatalytic activities than those of the common smooth ones.

8.
Phys Chem Chem Phys ; 15(26): 10921-9, 2013 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-23702827

RESUMO

Two poly(4-vinylpyridine)-b-polystyrene diblock copolymer/silica core-shell nanoparticles (P4VP-b-PS/SiO2 NPs) are developed in this work. Confirmed by DLS analysis and TEM observation, one comprises a SiO2 core surrounded by a P4VP-b-PS shell and the other comprises a P4VP-b-PS core surrounded by a SiO2 shell, which is facilely prepared by the in situ hydrolysis of tetraethyl orthosilicate (TEOS) using cationic P4VP-b-PS micelles obtained in a THF-H2C2O4 (aq, 0.1 mol L(-1)) mixture and a DMF-H2C2O4 (aq, 0.01 mol L(-1)) mixture as template, respectively. The SCA, CAH, SA and SEM measurements reveal that one-step deposition of P4VP-b-PS/SiO2 NPs with SiO2 cores formed at a high level of TEOS creates a superhydrophobic surface with an SCA of 160°, a CAH of 2° and an SA of around 4° originating from the formation of a typical micro-nanoscale binary structure (MNBS). For the NPs with SiO2 cores formed at a low level of TEOS, the superhydrophobicity with a SCA of 151°, CAH of 3° and SA of around 5° can be induced by the transition of the surface microstructure from an uneven and discontinuous MNBS, created by a one-step deposition process, to the coexistence of MNBS and a nanoscale structure (NS) after annealing with toluene for 30 min. In contrast, one-step deposition of P4VP-b-PS/SiO2 NPs with P4VP-b-PS cores and SiO2 shells usually results in the inhomogeneous precipitation of SiO2 from bulk P4VP-b-PS along with the production of micro-cracks, with which is impossible to achieve surface superhydrophobicity.

9.
Phys Chem Chem Phys ; 15(38): 15964-70, 2013 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-23959074

RESUMO

We have demonstrated significant evidence of a solvent-dependent synthesis of hierarchical Cu7S4 polycrystalline nanocage assemblies with controllable aggregation-based building blocks by a sacrificial Cu2O template approach. The formation of a hierarchical Cu7S4 polycrystalline nanocage is essentially determined by a Kirkendall effect, which is attributed to the tailored-aggregation behaviour of the nanoscale building blocks during the replacement/etching process in different polarities of solvent. The hierarchical Cu7S4 polycrystalline nanocage assembly of nanoparticle building blocks was prepared in pure water, while the hierarchical Cu7S4 polycrystalline nanocage assembly of twinned nanoplate building blocks was successfully synthesized in an anhydrous ethanol capping environment. Such a hierarchical Cu7S4 polycrystalline nanocage assembly of twinned nanoplate building blocks exhibits a higher photocatalytic activity than that of the common polycrystalline ones. A nanotwin-dependent photochemical mechanism has been proposed. Significantly, this study is of great importance in bottom-up assembly of controllable ordered architectures, and offers a good opportunity to understand the fundamental importance of the formation mechanism and growth process of hierarchical Cu7S4 polycrystalline nanocages with controllable aggregation-based building blocks.

10.
Phys Chem Chem Phys ; 15(26): 10904-13, 2013 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-23698563

RESUMO

For the first time, a facile, one-pot water/ethanol solution-phase transformation of Cu2(NO3)(OH)3 precursors into bicomponent CuO hierarchical nanoflowers is demonstrated by a sequential in situ dissolution-precipitation formation mechanism. The first stage produces a precursory crystal (monoclinic Cu2(NO3)(OH)3) that is transformed into monoclinic CuO nanoflowers during the following stage. Water is a required reactant, and the morphology-controlled growth of CuO nanostructures can be readily achieved by adjusting the volume ratio between water and ethanol. Such a bicomponent CuO hierarchical nanoflower serving as a promising electrode material for a nonenzymatic glucose biosensor shows higher sensitivity and excellent selectivity. The findings reveal that the different Cu(x)M(y)(OH)(z) (M = acidic radical) precursors synthesized in a water/ethanol reaction environment can be utilized to obtain new forms of CuO nanomaterials, and this unique water-dependent precursor-transformation method may be used to effectively control the growth of other metal oxide nanostructures.


Assuntos
Técnicas Biossensoriais , Cobre/química , Glucose/análise , Nanoestruturas/química , Técnicas Eletroquímicas , Eletrodos , Etanol/química , Polímeros de Fluorcarboneto/química , Água/química
11.
Chemosphere ; 329: 138643, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37031838

RESUMO

Element doping coupled with heterojunction construction and morphology control is an efficient way to improve the properties of photocatalytic materials. Here, a thiourea-modified 2D/2D cobalt-doped (BiO)2CO3/BiOCl heterojunction photocatalyst (denoted as Co-(BC/BL)Tu) was constructed by a simple one-pot hydrothermal method. The photocatalytic property of Co-(BC/BL)Tu product was evaluated by the photocatalytic degradation of tetracycline hydrochloride (TC-HCl). Compared with the pure (BiO)2CO3 sample, the as-prepared Co-(BC/BL)Tu product displayed outstanding visible-light-driven photodegradation property. The photodegradation rate constant k value of the Co-(BC/BL)Tu product was 5.2 times higher than that of pure (BiO)2CO3, which was the result of the synergistic effect of the 2D/2D structure, cobalt doping and type-Ⅱ heterostructures. It could simultaneously boost the visible light harvesting of the photocatalytic system as well as charge separation. This study provides a facile and promising strategy for constructing a high-effective photocatalytic system by combining morphology control engineering, doping engineering, and heterostructure engineering.


Assuntos
Cobalto , Tetraciclina , Luz , Tioureia
12.
Chemosphere ; 315: 137742, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36608890

RESUMO

Tailoring energy band structure of bismuth oxychloride (BiOCl)-based photocatalysts by virtue of the metal and/or non-metal elements is one of the promising strategy to address environmental issues, especially plays a crucial role in water remediation. However, it still remains a great challenge to balance the light-harvesting and charge carriers separation. Herein, a feasible strategy was proposed for the simultaneous integration of energy-band modulation and surface hydroxylation to alleviate the as-mentioned contradiction and long-standing issues. By using a simple one-pot hydrothermal method, In-S-co-doped BiOCl photocatalyst coupling with surface hydroxylation (denoted as In/BOC-S-OH) was prepared by the simultaneous co-precipitation and ripening process and exhibited a good photocatalytic activity for removing tetracycline (TC) under visible light-irradiation than the counterparts of In-doped BiOCl (In/BOC), S-doped BiOCl (In/BOC-S) or surface -OH modification BiOCl (In/BOC-OH). Such satisfied photocatalytic efficiency benefits from the synergistic effect on the visible light capture, charge migration and separation associated with the introduction of intermediate energy levels and surface defect, respectively. Accompanying with the introduction of In and S hetero-atoms intercalation, both the potentials of valence and conduction bands were adjusted and the reduction of the bandgap could promote the capture of photons. Meanwhile, the powerful polarization effect associated with the non-uniform charge distribution could promote the special separation of carriers. More importantly, the surface defects induced by hydroxylation could act as traps for photogenerated electrons to stimulate the rapid separation of carriers, thereby causing the cleavage of antibiotics on the catalytic surface. This research offers a reliable strategy and promising scheme via effective solar energy conversion and charge carrier separation to advance photocatalytic wastewater remediation.


Assuntos
Luz , Tetraciclina , Hidroxilação , Antibacterianos/química , Oxirredução
13.
ACS Appl Mater Interfaces ; 14(30): 34855-34866, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35867986

RESUMO

Dielectric ceramics with relaxor characteristics are promising candidates to meet the demand for capacitors of next-generation pulse devices. Herein, a lead-free Sb-modified (Sr0.515Ba0.47Gd0.01) (Nb1.9-xTa0.1Sbx)O6 (SBGNT-based) tungsten bronze ceramic is designed and fabricated for high-density energy storage capacitors. Using a B-site engineering strategy to enhance the relaxor characteristics, Sb incorporation could induce the structural distortion of the polar unit BO6 and order-disorder distribution of B-site cations as well as the modulation of polarization in the SBGNT-based tungsten bronze ceramic. More importantly, benefiting from the effective inhibition of abnormal growth of non-equiaxed grains, Sb introduction into SBGNT-based ceramics could effectively suppress the conductivity and leakage current density, enhancing the breakdown strength, as proved by the electrical impedance spectra. Consequently, a remarkable comprehensive performance via balancing recoverable energy density (∼3.26 J/cm3) and efficiency (91.95%) is realized simultaneously at 380 kV/cm, which surpasses that of the pristine sample without the Sb dopant (2.75 J/cm3 and 80.5%, respectively). The corresponding ceramics display superior stability in terms of fatigue (105 cycles), frequency (1∼200 Hz), and temperature (20∼140 °C). Further charge-discharge analysis indicates that a high power density (89.57 MW/cm3) and an impressive current density (1194.27 A/cm2) at 150 kV/cm are achieved simultaneously. All of the results demonstrate that the tungsten bronze relaxors are indeed gratifying lead-free candidate materials for dielectric energy storage applications.

14.
Chemosphere ; 307(Pt 3): 135979, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35977567

RESUMO

Bismuth oxychloride (BiOCl) has appeared as a popular candidate in photocatalysis field but is plagued by its poor visible light harvesting and low carriers-flow steering inherited from wide band gap. Integration of doping and heterojunction engineering into the bulk has proven to be an optimal and generally applied method for enabling excellent photocatalytic activity. Nevertheless, the previous reported BiOCl-based photocatalysts fabricated by the above strategies are still suffered from harsh synthesis process, poor interface stability and narrow application area. Here, we introduce a facile one-pot hydrothermal strategy to achieve in-situ growth of TaON as a medium on the surface of Bi2O3 and S-doped BiOCl (denoted as S-BiOCl) for constructing ternary TaON/Bi2O3/S-BiOCl heterostructures, which were obtained by the simultaneous coprecipitation and ripening process. Current investigation suggests that such a unique TaON/Bi2O3/S-BiOCl exhibits a relatively much higher photocatalytic activity for visible light-driven removal of rhodamine B (RhB), tetracycline (TC) and tetracycline hydrochloride (TC-HCl) than those of hybrid Bi2O3/S-BiOCl and pristine S-BiOCl. It is ascribed to the synergetic effect on the introduction of S dopant level in BiOCl lattice as well as the construction of intimate double heterointerfaces among Bi2O3, TaON and S-BiOCl, which endows the TaON/Bi2O3/S-BiOCl photocatalysts with considerable advantages for highly elevating photocatalytic performances, such as the intensive optical absorption, high redox potential as well as high-efficient photocharge separation originated from type-I and Z-scheme pathways. This work delivers novel insights for design and one-pot preparation of high-active BiOX (X = Cl, Br and I)-based photocatalysts towards organic dye and antibiotic removal in the future research.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Antibacterianos/química , Bismuto , Catálise , Luz , Tetraciclina , Poluentes Químicos da Água/química
15.
Nanoscale Adv ; 3(16): 4851-4857, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36134308

RESUMO

Heterojunction engineering is an effective strategy to enhance the photodegradation activity via improving the spatial charge separation. However, the poor interface interactions and stability limit the photocatalytic activity and stability of traditional heterojunctions. Herein, robust BiOCl/ZnO p-n heterojunctions with semi-coherent interfaces were prepared by a one-pot hydrothermal method to improve the activity and stability toward photocatalytic degradation than that of the counterpart, in which the semi-coherent interfaces exhibited lower phase boundary energy, resulting in highly-stable interfaces between BiOCl and ZnO as well as the formation of the built-in electric field in this robust p-n heterojunction for enhanced charge separation. The cycle test results verified that the BiOCl/ZnO heterojunctions with semi-coherent interfaces can maintain the photocatalytic degradation activity at the initial level even after 10 cycles, while deactivation of the sample without semi-coherent interfaces occurred after 3 cycles only. Optical and electrical properties revealed that BiOCl/ZnO heterojunctions with semi-coherent interfaces possessed the highest electron migration and charge separation efficiency, resulting in the highest photodegradation activity. Density functional theory (DFT) calculations and electron spin-resonance (ESR) results verified that the enhanced charge separation was assigned to the type-II photocatalytic mechanism, leading to the enhancement of ˙OH and ˙O2 - reactive oxygen species. This work would provoke the development of one-step construction of new highly active BiOX (X = Cl, Br, and I)-based heterogeneous photocatalysts with stable semi-coherent interfaces.

16.
J Nanosci Nanotechnol ; 21(1): 495-504, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33213648

RESUMO

The production and evolution of fractures during coal creep will directly affect the occurrence, extraction and flow law of gas in a coal seam. The coal fracture evolution under creep conditions was studied by qualitative analysis and quantitative characterization. At a room temperature of 24 °C, triaxial compression creep tests of coal samples from the Zhaogu No. 2 coal mine in Jiaozuo were carried out under different loading conditions (0 MPa, 6 MPa, 9 MPa and 12 MPa), and low field nuclear magnetic resonance technique tests and industrial CT scanning experiments were performed. The obtained CT images were analyzed with the MATLAB software for equalization and binary image processing. The development and distribution of fractures in coal samples under different loading conditions were studied. The results show that the internal fractures are unevenly distributed and controlled by the main fracture, and the expansion direction of fractures is parallel to the direction of the maximum effective compressive stress. The number of fractures shows an increasing trend with the increase of axial stress, and the pace of growth of new fractures accelerates. The primary fractures in the coal body expand and generate new fractures, which improves the connectivity of the fractures in the coal body. The research results can provide a basis for studying the gas flow rule around the borehole and determining the influence range of the borehole.

17.
Nanoscale ; 13(27): 11867-11877, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34190279

RESUMO

Mesocrystals with highly ordered subunits can provide good charge transfer tunnels and more active sites for catalytic reactions. So far, single-component mesocrystals have been well-developed in metals or metal oxides in the past decades, but the construction of mesocrystals in nanocomposites has been a great challenge. Herein we demonstrated a simple, one-pot wet chemical strategy for the preparation of plate-like Ag-Cu2O composited mesocrystals (CMCs) without any organic capping agent, which broke through the traditional dependence on organic capping agents for the synthesis of mesocrystals. As expected, these unprecedented Ag-Cu2O CMCs displayed superior visible-light-driven photodegradation performance toward tetracycline solution compared to the core-shell Ag@Cu2O and pure Cu2O photocatalysts. The improved photocatalytic activity of Ag-Cu2O CMCs could be ascribed to the synergistic effect of an ordered crystallographic orientation, the Schottky barrier and localized surface plasmon resonance (LSPR) for simultaneously enhancing charge separation and transfer as well as visible light harvesting. This research might stimulate in-depth investigations on the exploration of new synthetic methods for the design and construction of novel composited mesocrystals.

18.
Nanoscale ; 12(32): 16657-16677, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32766646

RESUMO

Micro-/nanostructures exposed with special crystallographic planes (surface or crystal facets) exhibit distinctive physicochemical properties because of their unique atomic arrangements, resulting in their widespread applications in the fields of catalysis, energy conversion, sensors, electrical devices and so on. Therefore, tremendous progress has been made in facet-dependent investigation of various micro-/nanocrystals over the past decades. However, a lot of beginners including undergraduate students as well as graduate students lack systematic knowledge and don't know how to identify the Miller indices of a crystallographic plane in the actual research process. So far, to the best of our knowledge, there is no specialized review article in this respect. Herein, we present a tutorial and a comprehensive review on the identification of the Miller indices of a crystallographic plane, including fundamental theory, universal methods based on different case studies, and matters needing attention. Hopefully, this tutorial review will be a beneficial theoretical and practical reference for beginners currently focusing on the controllable preparation and facet-dependent investigation of micro-/nanocrystals.

19.
Nanoscale ; 12(3): 1912-1920, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31907507

RESUMO

As promising photocatalysts, nano-sized Cu2O particles suffer from severe charge recombination and insufficient light absorption, resulting in their unsatisfactory photocatalytic performance. Herein, we have designed a core-shell structured Au nanorod@octahedron Cu2O with preferentially edge-loaded Au nanoparticles (Au(R)@Cu2O-Au(P)) for an efficient photocatalytic degradation reaction. A "push-pull" synergetic effect of Au(R) and Au(P) was found to improve the transfer and separation of charge carriers from the bulk to the surface of Cu2O. Furthermore, the light beyond Cu2O particles' absorption range can penetrate the shell (Cu2O) and for being utilized by the Au(R) core via its localized surface plasmon resonance effect (LSPR) to inject hot electrons into the conduction band of Cu2O for photocatalytic reactions. Moreover, the investigation of the size effect of Au(R)@Cu2O-Au(P) reveals that both the short charge transfer distance and the more efficient charge transfer have contributed to its enhanced photocatalytic activity.

20.
Chem Commun (Camb) ; 55(64): 9418-9431, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31334510

RESUMO

Water is one of the most commonplace solvents employed in wet chemical synthesis; however, it can sometimes play important roles such as an effective inducer or morphology-directing agent when introduced into a special reaction system, resulting in the formation of inorganic micro-/nanostructures with well-defined configurations. A better understanding of the key roles of water in the chemical synthesis will unlock a door to the design of many more novel single-component and hybrid nanocomposite architectures. Therefore, it is imperative to comprehensively review the topic of water-guided synthesis of well-defined micro-/nanostructures. Unfortunately, the significance of water has been underestimated and an in-depth study about the exact action of water in morphology-control is still lacking. In this review, we focus on the recent advances made in the development of the shape-controlled synthesis of inorganic micro-/nanostructures achieved by only adjusting the amount of water through some typical examples, including noble metals, metal oxides, perovskites, metal sulfides and oxysalts. In particular, the theory principles, synthesis strategies and growth mechanisms of the water-guided synthesis of well-defined inorganic micro-/nanostructures have been mainly highlighted. Finally, several current issues and challenges of this topic that need to be addressed in future investigations are briefly presented.

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