Facile One-step Solvothermal Route Research Articles

The preparation of Bi3+ quantum dots modified SnS nanosheets gas sensor for detecting TEA

A facile one-step solvothermal route was exploited to synthesis the Bi3+ quantum dots decorated flower-like SnS (tin sulfide) nanosheets (the Bi3+-SnS). The result of the SEM analysis techniques showed that the 6% (the molar mass proportion) Bi3+-SnS samples exhibit optimum self-assembly pearl-flower morphology formed from nanosheets than those of 3% and 9%. The XRD and TEM techniques display the samples of 6% Bi3+-SnS with orthorhombic and obvious crystal lattices. What's more, the gas sensitive characteristic revealed that the sensor based 6% Bi3+-SnS exhibited a relatively highter sensing performance than others samples to 50 ppm TEA at the optimal operating temperature of 200 °C. Hence this study may be helpful for constructing a promising material of the Bi3+ quantum dots decorated SnS for detecting TEA at lower temptature in practical application.

Physical and Electrochemical Properties of Graphene Decorated with ZnO Hollow Spheres for Supercapacitor Applications

Single-layer graphene-ZnO hollow sphere (SLG-ZnO(HS)) composites were successfully prepared through facile one-step solvothermal synthesis route. The morphological structures of the samples were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Hollow spheres consisting of ZnO nanoparticles with a diameter of approximately 30 nm are decorated to both sides of the SLG sheets. The electrochemical performances were tested by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance (EIS). The SLG-ZnO(HS) composite electrode synthesized at a concentration of 0.25 mM Zn precursor exhibited an enhanced specific capacitance of 34.7 F/g at a scan rate of 1 mV/s with energy and power densities of 5.39 W h/kg and 1.73 kW/kg, respectively.

Orange emissive N-doped carbon dots and their application in detection of water in organic solvents and the polyurethane composites

In this work, efficient orange emissive N-doped carbon dots (N-CDs) were synthesized through a facile one-step solvothermal route using 1,4-phenylene diisocyanate as the only raw precursor. The as-prepared N-CDs exhibited strict excitation independent luminescence with a maximum emission peak at 581 nm. The absolute photoluminescence quantum yield was up to 38%. A reasonable formation process of N-CDs was explored in detail. Interestingly, the N-CDs was sensitive to water and thus, could be exploited as an excellent fluorescent probe directly for quantitative detection of water in organic solvents. Moreover, various orange-emitting N-CDs/polymer composites were achieved by simply incorporating the N-CDs into different polymer matrices. The N-CDs could be better uniformly dispersed in polyurethane (PU) matrix through the in situ polymerization technique, and the emission intensity of N-CDs/PU composite films could be linearly modulated by changing the N-CDs concentration. These investigations broaden promising application potentials of CDs in sensor and optoelectronic devices.

Multifunctional Catalyst CuS for Nonaqueous Rechargeable Lithium-Oxygen Batteries.

Copper sulfide with flower-like (f-CuS) and carambola-like (c-CuS) morphologies was successfully synthesized by a facile one-step solvothermal route with different surfactants. When employed as cathode catalysts for lithium-oxygen batteries (LOBs), f-CuS outperforms c-CuS in terms of oxygen electrochemistry, judging from the faster kinetics and the higher reversibility of oxygen reduction/oxidation reactions, as well as the better LOB performance. Moreover, an abnormal high-potential discharge plateau was observed in the discharge profile of the LOB. To understand the different performances of f-CuS and c-CuS and the abnormal high-potential plateau, theoretical calculations were conducted, based on which a mechanism was proposed and verified with experiments. On the whole, CuS can work as a multifunctional catalyst for promoting LOB performance, which means that the dissolved CuS in LiTFSI/TEGDME electrolyte can serve as a liquid catalyst by the redox couples of Cu(TFSI)2/Cu(TFSI)2-/Cu(TFSI)22-, in addition to the function as a traditional solid catalyst in the cathode.

Fe2O3-decoration and multilayer structure design of Ti3C2 MXene materials toward strong and broadband absorption of electromagnetic waves in the X-band region

Although strong and effective absorption of electromagnetic waves in the X-band region is of utmost importance for practical applications, it still faces many challenges. In this work, we prepared Fe2O3-decorated Ti3C2 composites via a facile one-step solvothermal route. Scanning electron microscopy micrographs showed that Fe2O3 particles effectively cover the Ti3C2 surface and insert into the Ti3C2 layers. X-ray diffraction patterns demonstrated that the Fe2O3 particles are beneficial for the Ti3C2 delamination. A high attenuation constant and suitable impedance matching enabled wide-range microwave absorption properties; however, the minimum reflection loss was relatively high. To achieve both wide bandwidth and strong absorption, we designed a multi-layered structural absorber. When the thickness was 1.9 mm, the fourfold-layered structural absorber exhibited the optimal absorption properties with the minimum RL value of − 49.68 dB at 9.922 GHz and RL less than − 10.82 dB in the entire X-band region. Therefore, the synthesized multi-layered structural Ti3C2/Fe2O3 composites can be used for practical applications as a high-performance microwave absorber in the X-band region.

Synthesis and application of magnetic@layered double hydroxide as an anti-inflammatory drugs nanocarrier

BackgroundMagnetic nanocomposites with a core–shell nanostructure have huge applications in different sciences especially in the release of the drugs, because of their exclusive physical and chemical properties. In this research, magnetic@layered double hydroxide multicore@shell nanostructure was synthesized by the facile experiment and is used as novel drug nanocarrier.MethodsMagnetic nanospheres were synthesized by a facile one-step solvothermal route, and then, layered double hydroxide nanoflakes were prepared on the magnetic nanospheres by coprecipitation experiment. The synthesized nanostructures were characterized by FTIR, XRD, SEM, VSM, and TEM, respectively. After intercalation with Ibuprofen and Diclofenac as anti-inflammatory drugs and using exchange anion experiment, the basal spacing of synthesized layered double hydroxides was compared with brucite nanosheets from 0.48 nm to 2.62 nm and 2.22 nm, respectively.ResultsThe results indicated that Ibuprofen and Diclofenac were successfully intercalated into the interlay space of LDHs via bridging bidentate interaction. In addition, in-vitro drug release experiments in pH 7.4, phosphate-buffered saline (PBS) showed constant release profiles with Ibuprofen and Diclofenac as model drugs with different lipophilicity, water solubility, size, and steric effect.ConclusionThe Fe3O4@LDH-ibuprofen and Fe3O4@LDH-diclofenac had the advantage of the strong interaction between the carboxyl groups with higher trivalent cations by bridging bidentate, clarity, and high thermal stability. It is confirmed that Fe3O4@LDH multicore-shell nanostructure may have potential application for constant drug delivery.

Performance modulation of energy storage devices: A case of Ni-Co-S electrode materials

Abstract Nickel cobalt sulfides are deemed as promising electrode materials for energy storage devices due to their rich redox active sites as well as superior conductivity. Herein, we report P-doped Ni-Co-S@C (PNCS@C) assemblies consisting of many nanosheets through facile one-step solvothermal route and a subsequent phosphorization process. The as-obtained product is utilized as electrode material for supercapacitor, which shows a specific capacity of 1026 C g−1 at current density of 1 A g−1. An asymmetric supercapacitor (ASC) delivers an energy density of 131.40 Wh kg−1 at a power density of 1355.37 W kg−1. As anode material for lithium ion battery, it presents a discharge capacity of 2300.10 mAh g−1 at 0.1 A g−1. The superior electrochemical performance could be attributed to their unique spatial architectures and synergistic effect between composites.

Fabrication of dopamine enveloped WO3−x quantum dots as single-NIR laser activated photonic nanodrug for synergistic photothermal/photodynamic therapy against cancer

Tungsten oxide is a promising nanodrug in phototherapy via transforming light energy to reactive oxygen species and heat. Nevertheless, the phototherapeutic activity of the tungsten oxide nanomaterials is generally activated under 980 nm laser, which is close to the absorption of normal tissue, resulting in unfavorable heating effect on normal tissues. Therefore, the tungsten oxide nanomaterials which can be excited under 808 nm are highly required to avoid overheating and obtain deep tissue penetration of near-infrared (NIR) laser. Here, we successfully synthesized a novel dopamine enveloped tungsten oxide nanodots (WO3−x/Dpa-Mel NPs) via facile one-step solvothermal route, using dopamine as the template and reductant in triethylene glycol solvent. Under the 808 nm laser irradiation, the as-obtained WO3−x/Dpa-Mel NPs exhibit excellent photodynamic activity and stability. Meanwhile, the WO3−x/Dpa-Mel NPs also possess high photothermal conversion property. Thus, the photothermal therapy (PTT) and photodynamic therapy (PDT) can be triggered simultaneously under single 808 nm laser irradiation. Additionally, the inherited good biocompatibility and dispersity in aqueous solution from dopamine hydrochloride (Dpa-Mel) also make the WO3−x/Dpa-Mel NPs more suitable for in vivo application. The as-obtained WO3−x/Dpa-Mel NPs exhibit an excellent synergistic phototherapy effect on solid tumor ablation in vivo without damaging healthy tissues under single 808 nm NIR light irradiation, indicating WO3−x/Dpa-Mel NPs can serve as a multifunctional therapeutic nanoplatform to realize the synergistic cancer therapy.

Facile synthesis of cobalt-zinc ferrite microspheres decorated nitrogen-doped multi-walled carbon nanotubes hybrid composites with excellent microwave absorption in the X-band

Herein, nitrogen-doped multi-walled carbon nanotubes/cobalt-zinc ferrite (NMWCNTs/Co0·5Zn0·5Fe2O4) hybrid composites were synthesized through a facile one-step solvothermal route. Results of morphology observations revealed that Co0·5Zn0·5Fe2O4 microspheres were uniformly loaded on the surface of NMWCNTs and three-dimensional (3D) conductive networks were in-situ constructed by the entanglement of NMWCNTs in the as-prepared hybrid composites. Moreover, the influence of contents of NMWCNTs on the electromagnetic parameters and microwave absorption properties of NMWCNTs/Co0·5Zn0·5Fe2O4/paraffin wax composites were elaborately investigated. It was found that the obtained hybrid composites demonstrated superior microwave absorption performance in the X-band. Remarkably, the minimum reflection loss reached −64.7 dB with a matching thickness of 3.1 mm and effective absorption bandwidth achieved 4.3 GHz (11.7–16.0 GHz) with a thickness of merely 2.1 mm. Furthermore, a dual-band (C and Ku bands) microwave absorption characteristic was observed in the obtained hybrid composites. Besides, the microwave absorption properties of as-prepared hybrid composites could be facilely tuned by changing the matching thicknesses and contents of NMWCNTs. The superior microwave absorption properties of obtained hybrid composites mainly originated from the synergistic effects of magnetic loss, conduction loss and dielectric loss, and optimized impedance matching. It was believed that our results could be helpful for the structural design and facile fabrication of 3D MWCNTs-based hybrid composites as high-efficient microwave absorbers.

Synthesis of high-efficient red carbon dots for pH detection

A facile one-step solvothermal route for the preparation of high-efficient red fluorescence carbon dots (RCDs) is developed using 2-aminophenol as carbon source. The as-prepared RCDs indicate excitation-independent emission at 615 nm, high absolute photoluminescence (PL) quantum yield (24%) in ethanol, excellent water solubility, high optical stability and sensitive pH response behavior. The RCDs-based “off-on” reversible probe can be used to detect H+ and OH−. The quenching and recovering effects can be obviously observed by naked eyes due to the combination effect between the target ions and the surface functional groups of RCDs, resulting in breaking or recombination of the quenchers. Moreover, a remarkable fluorescence enhancement behavior with the increase of pH from 4 to 13 can be induced by the RCDs, which can be also used to detect H+ and OH− in urine of cattle and lake water, exhibiting a promising platform of the RCDs for environmental and biological sensing applications.

Facile one-step solvothermal synthesis of a luminescent europium metal-organic framework for rapid and selective sensing of uranyl ions.

A simple, cost-effective, and portable uranium sensory material with adequate selectivity is increasingly urgent and would be of great importance in environmental monitoring of radionuclides. Herein, we report a novel luminescent europium metal-organic framework (Eu-MOF) with plenty of Lewis basic sites for binding uranyl ions (UO22+), the most common form of uranium in solution, through a facile one-step solvothermal synthetic route. The mesoporous structure consists of europium nodes and flexible nitrogen-containing ligands with a 29.2 × 20.5Å2 channel along the c-axis. Furthermore, the obtained material displays characteristic fluorescence of trivalent Eu3+ and could be applied as a turn-off sensory probe targeting UO22+ in solution. Differential fluorescent quenching occurred upon a series of potential interfering ions compared to UO22+ and the detection limit as low as 0.9μM was achieved with a rapid response. Graphical abstract.

One step synthesis of Fe3O4@C composite as a high performance anode material for Li-ion batteries

Fe3O4@C composite was designed and synthesized by a facile one-step solvothermal route as an anode material for Li-ion batteries (LIBs). The carbon shell can effectively prevent the aggregation and buffer the volume expansion during charge/discharge process. The electrochemical performance displays that the Fe3O4@C composite exhibits high reversible capacity and good cycling performance. In particular, it displays excellent cycling stability at 2 C rate (640.5/642.2 mA h g−1 after 1000 cycles). The results indicate a simple and useful route to prepare Fe3O4@C composite as a promising LIBs anode material.

Fabrication of UV–Vis-NIR-driven photocatalysts Ag/Bi/BiOCl0.8Br0.2 with high catalytic activity

Abstract In this work, multiple heterojunction Ag/Bi/BiOCl0.8Br0.2 photocatalysts with novel porous micro-flower structure were fabricated via a facile one-step solvothermal route and characterized systematically. The TEM and HRTEM images clearly showed the heterogeneous nanostructures at the interface between Ag/Bi and BiOCl0.8Br0.2. The as-prepared Ag/Bi/BiOCl0.8Br0.2 composites displayed a strong optical absorption in the region of 250–1500 nm, especially in the unexploited near infrared region which accounts for most of the sunlight. The multiple heterojunction photocatalyst exhibited an outstanding photocatalytic activity for the degradation of Rhodamine B under the UV, visible and NIR light irradiation, respectively. The highly enhanced photocatalytic activity was attributed to the synergistic effects, including the reduced band gap, the surface plasmon resonance effect, efficient charge separation of photo-generated electron-holes. On the basis of the radical species trapping experiments, the holes and superoxide radicals were confirmed to be the mainly active species involved in the degradation of Rhodamine B under the NIR light irradiation. This study provides a novel strategy for designing highly performance plasmonic photocatalysts under the whole solar light irradiation.

One‐step synthesis and characterisation of LuAG nanoparticles via solvothermal route

Lutetium aluminium garnet (Lu3Al5O12, LuAG) nanoparticles were well prepared via a facile and low temperature one-step solvothermal route using aluminium nitrate and lutetium nitrate as raw materials and ethylenediamine (en) solution as the reaction medium. Here, en was employed both as the chelating agent and structure-directing agent. Influences of the reaction medium, temperature, time and dispersant on the synthesis of crystalline LuAG nanoparticles were investigated. Characterisation of LuAG nanoparticles was performed using X-ray diffraction, Fourier transform infrared, transmission electron microscopy and selected area electron diffraction. Optimum synthesis conditions of single-phase LuAG nanoparticles have been determined. The addition of citric acid as a dispersant can effectively decrease the particle size and increase dispersion of crystalline LuAG nanoparticles.

In situ grown hierarchical 50%BiOCl/BiOI hollow flowerlike microspheres on reduced graphene oxide nanosheets for enhanced visible-light photocatalytic degradation of rhodamine B

50%BiOCl/BiOI/reduced graphene oxide (50%BiOCl/BiOI/rGO) composite photocatalyst was synthesized successfully by a facile one-step solvothermal route in this work. Reduction of graphene oxide (GO) took place in the process of solvothermal reaction and a new Bi-C bond between rGO and 50%BiOCl/BiOI was formed. The introduction of rGO affected the morphology of 50%BiOCl/BiOI, resulting in the transformation of 50%BiOCl/BiOI from solid microspheres to hollow microspheres. Both the introduction of rGO and formation of 50%BiOCl/BiOI hollow microspheres can facilitate the light absorption. The strong interaction between 50%BiOCl/BiOI and rGO and the electrical conductivity of rGO greatly improved the effective separation of photogenerated carriers. Hence, GOB-5 demonstrated the highest photocatalytic activity which was over twice of the pristine 50%BiOCl/BiOI in the presence of visible light. Mechanism study revealed that 50%BiOCl/BiOI generated electrons and holes in the presence of visible light, and holes together with O2− generated from reduction of O2 by electrons degraded the pollutant directly. Overall, this work provides an excellent reference to the synthesis of chemically bonded BiOX/BiOY (X, Y = Cl, Br, I)/rGO nanocomposite and helps to promote their applications in environmental protection and photoelectric conversion.

Bifunctional Ag Doped SnS2 Photocatlyst and Electrocatlyst for Solar Energy Appliations

SnS2, as a mid-band-gap semiconductor shows a good potential as an excellent photocatalyst due to its low cost, wide light spectrum response and environment-friendly nature. At the same time, it is also considered as a prospective counter electrode (CE) electrocatlayst for dye-sensitized solar cells (DSSC) due to its good electrocatalytic property. However, to meet the demand of large-scale commercialization of both applications, SnS2 with superior properties are required. Doping is a facile method to manipulate the optical and chemical properties of semiconductor materials simultaneously. In this work, Ag-doped SnS2 samples with various doping amounts are prepared via a facile one-step solvothermal route. The product was characterized by XRD, SEM, TEM and UV-VIS spectrometry. The photocatalytic activity of the Ag-doped SnS2 is studied by degradation of methylene blue dye under solar light irradiation. It’s found increasing Ag dopant concentration can effectively increase solar light adsorption efficiency and accelerated heterogeneous photocatalysis. The optimal concentration of Ag dopant concentration was found to be 5 % with the highest rate constant of 1.8251 hour-1. It is also found that the DSSC based on 5% Ag-doped SnS2 CE demonstrates the best performance showing an impressive photovoltaic conversion efficiency of 8.70 % which exceeds the efficiency of Pt-based DSSC (7.88%) by 10.41%, while the DSSC consisting of undoped SnS2 only exhibits a PCE of 6.47%. Such enhanced efficiency of DSSC is attributed to the effectively improved electrocatalytic activity and mixed conductivity resulted from Ag dopant. Therefore, a proper amount of Ag doping can effectively increase the photocatalytic and electrocatalytic performance of SnS2 and may pave a new way for large-scale solar energy applications.

Novel Li3VO4/MoS2 composite materials with high electrochemical performance as anode for lithium ion batteries

Novel Li3VO4/MoS2 composite used as anode materials for lithium ion batteries was first synthesized through a facile one-step solvothermal route. The Li3VO4/MoS2 composite compounds achieved excellent electrochemical performance such as high specific capacity, superior stable cycling and good rate performance. Under a current density of 100mAg−1, the discharge/charge capacity of the Li3VO4/MoS2 composite electrode was 690/679mAhg−1 after 100 cycling, which was superior to the Li3VO4-based anode materials reported previously. The unique coordination effect originated from the one-step preparation process was responsible for the high electrochemical performance of Li3VO4/MoS2 composite.

Facile one-step synthesis of Ag@CeO2core–shell nanospheres with efficient catalytic activity for the reduction of 4-nitrophenol

Ag@CeO2 core–shell nanospheres were synthesized by a facile one-step solvothermal route from Ce(NO3)3·6H2O, AgNO3, poly(N-vinylpyrrolidone) (PVP), and ethanol. The structure, composition, BET specific surface area and optical properties of Ag@CeO2 core–shell nanospheres were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, high resolution transmission electron microscopy, N2 adsorption–desorption isotherm analysis, and UV-vis diffuse reflectance spectroscopy. Field emission scanning, high resolution transmission electron microscopy and X-ray photoelectron spectroscopy etching results of the as-synthesized Ag@CeO2 nanospheres revealed that the as-synthesized Ag@CeO2 nanospheres consist of a Ag core and a CeO2 shell. The catalytic results demonstrated that the as-synthesized Ag@CeO2 nanospheres possessed higher catalytic activity than pure Ag (which was synthesized by a similar solvothermal method) in the reduction of 4-nitrophenol. Their enhanced catalytic activity is found to be due to the unique oxidized Ag species induced by the strong interaction between the core surface of Ag nanospheres and surface defects (oxygen vacancies) of the CeO2 shell. The herein proposed Ag@CeO2 core–shell nanospheres are promising catalytic candidates for the reduction of p-nitrophenol because of their simple preparation route and high catalytic activity.

Preparation and characterisation of TiO2 nanorod and nanotube films as photoanodes for dye-sensitised solar cells

TiO2 nanorod arrays are successfully synthesised on the transparent conductive fluorine-doped tin oxide glass through a facile one-step solvothermal route without any surfactant and template, TiO2 nanotube arrays were obtained through acid etching afterwards. Dye-sensitised solar cells based on these two different one-dimensional TiO2 photoelectrodes show the power conversion efficiency of 1.68 and 3.89% for nanorod and nanotube cells, respectively. The nanotube cell has better photoelectric performance than nanorod cell because of lower recombination, faster electron transformation, higher specific surface area for adsorbing more dye molecules and superior light scattering capacity for boosting the light-harvesting efficiency.

High-performance dye-sensitized solar cells based on Ag-doped SnS2counter electrodes

Tin disulfide (SnS2) has been considered as a prospective counter electrode (CE) material for dye-sensitized solar cells due to its good electrocatalytic properties. However, its low electronic and ionic conductivities pose challenges for using it in high-performance dye-sensitized solar cells (DSSCs). Herein, doping is utilized to improve the properties of SnS2 for application as a DSSC counter electrode. Ag-doped SnS2 samples with various doping amounts are prepared via a facile one-step solvothermal route. It is found that the DSSC based on a 5% Ag-doped SnS2 CE demonstrates the best performance showing an impressive photovoltaic conversion efficiency (PCE) of 8.70% which exceeds the efficiency of a Pt-based DSSC (7.88%) by 10.41%, while the DSSC consisting of undoped SnS2 only exhibits a PCE of 6.47%. Such an enhanced efficiency of the DSSC is attributed to the effectively improved electrocatalytic activity and mixed conductivity resulting from the Ag dopant. Therefore, the Ag-doped SnS2 CE proves to be a promising alternative to the expensive Pt CE in DSSCs and may pave a new way for large-scale production of new-generation DSSCs.