One-pot Solvothermal Process Research Articles

Fabrication of a novel microflower BiOCl composite incorporated with rosemary powder for enhanced oxygen vacancies and visible-light photocatalytic efficiency

Incorporating metallic or nonmetallic compounds is a promising method for enhancing the oxygen vacancies (OVs), charge transport, and visible light absorption of a bismuth oxychloride (BiOCl) semiconductor. This research aims to improve the properties of BiOCl by incorporating rosemary powder (RPC). BiOCl photocatalysts with enhanced OVs were synthesized through the addition of 1–4 wt% of RPC using a one-pot solvothermal process. The addition of 3 % RPC resulted in the formation of very small particles on the BiOCl lamellar structures, which were aligned with the (002) plane of carbon quantum dots (CQDs). The uniformly distributed CQDs transformed the BiOCl microstructure from a two-dimensional lamellar structure to a three-dimensional floral structure, leading to an increased surface area and pore volume. The incorporation of RPC enhanced the visible light absorption capacity of BiOCl. The carbon atoms in RPC readily attach to oxygen atoms in the Bi-O bond, disrupting the Bi-O lattice bond and forming OVs. The addition of RPC contributed to a higher number of OVs, which impacted both the energy difference between the valence and conduction bands and their locations. This resulted in better charge transfer and enhanced active species formation. The 3 %-RPC-BOC photocatalyst had the highest efficiency, achieving a 98 % degradation of rhodamine B (RhB) and a 45 % removal of organic carbon within 48 min under visible light. This composite also had excellent stability and reusability, as its crystal structure remained unaltered even after conducting 7 cycles. The primary active species of 3 %-RPC-BOC system is the superoxide radical (·O2-), while the hydroxyl radical (·OH) and hole (h+) operate as minor active species. Additionally, the 3 %-RPC-BOC achieved a high tetracycline (TC) removal rate of 82.1 %, which is 2.21 times higher than that of pure BiOCl.

Fabrication of Carbon Dots with Singlet Oxygen Generation and Their Potential Photodynamic Therapy Applications.

Due to the unique chemical and biomedical properties of carbon dots (CDs), they have increasingly obtained the attention in many research fields, for example, bioimaging, fluorescence sensing, and drug delivery, etc. Recently, it was found that, under light excitation, CDs can also be exploited as a novel photosensitizer to prepare reactive oxygen species (ROS), which expand their applications in the field of photodynamic therapy for cancer treatment. Nevertheless, the high cost and complex fabrication approach of CDs significantly limit their applications. To address this issue, bottom-up routes usually utilize sustainable and inexpensive carbon precursor as starting materials, employed N,N-dimethylformamide (DMF) or ethanol as an environmental-friendly solvent. Bottom-up approach was energy efficient, and the purification process was relatively simple by dialysis. Therefore, carbon dots (CDs) were facilely fabricated in a one-pot solvothermal process using 1-aminoanthraquinone as a precursor, and their application as photosensitizers for in vitro antitumor cells, especially photodynamic therapy (PDT) was established. Then the photophysical and nanoscale dimensions properties of the fabricated CDs were characterized via TEM, UV-visible, fluorescence, and FT-IR spectroscopy. The synthesized N-doped CDs can easily dissolve in water, possess very low biotoxicity, yellow-light emission (maximum peak at 587nm). More importantly, PDT studies demonstrated that the obtained CDs possess a high singlet oxygen yield of 35%, and exhibit significant phototoxicity to cancer cells upon 635nm laser irradiation. These studies highlight that N-doped CDs can be facilely synthesized from only one precursor, and are a potentially novel theranostic agent for in vivo PDT.

Improved performance of Pseudomonas fluorescens lipase immobilized on a magnetic mesoporous solvothermal hybrid-nanocarrier and its application in ultrasonication assisted estolide synthesis

The exponential growth of the biotechnological market necessitates the exploring novel, economically viable materials for enzyme immobilization to enhance the biocatalyst performance. This study involves preparing a hybrid carrier with a magnetic mesoporous nature, using milled rice husk (MRH) and multi-walled carbon nanotubes (MWCNTs) via a one-pot solvothermal process at 200 °C for 6 h. The carrier, rich in-NH2 groups, was chemically bonded to Pseudomonas fluorescens lipase (PFL) using EDC/NHS cross-linkers. The synthesized support achieved a maximum PFL loading of 94.92 mg of protein per gram of support. Moreover, the maximum activity recovery was achieved at 1196 %, under the optimal conditions: immobilization temperature 25℃, pH 9.0, immobilization time 2 h and PFL mass concentration 4 mg/mL. Subsequently, the derived enzyme was used to catalyze ricinoleic acid esterification to synthesize estolide under ultrasound-assisted conditions. The optimized principal parameters for reaction temperature, reaction time, and immobilized lipase loading were respectively determined to be 48.99 °C, 1.60 h, and 3.09 % via response surface methodology. Ricinoleic acid conversion reached 65.23 % under the optimal conditions with the assistance of 40 % power and 40 kHz ultrasonic frequency. Furthermore, remarkable operational stability was also observed, with a retention rate of 49.28 %, even after 10 consecutive batches. This study demonstrates promising prospects for industrial-scale application using ultrasound as a fast and ecologically friendly procedure.

Solvothermally synthesized magnetite nanorods for application in magnetic hyperthermia and photothermia

The development of the multi-functional nanostructures has recently been of particular interest in therapeutic research for various diseases including atherosclerosis, cancer, etc. Indeed, the use of multi-responsive nanostructures that can remotely be activated by different stimuli is a promising strategy to combine the advantages of standalone methods and overcome their intrinsic drawbacks. In this regard, thermal treatment using heat-generating magnetic nanostructures that can remotely respond to a wide range of electromagnetic stimuli is of especial importance, mainly applied through magnetic hyperthermia therapy (MHT) and photothermal therapy (PTT) modalities. In this work, magnetite (Fe3O4) nanorods (MNRs) were synthesized using a one-pot solvothermal process. Adjusting the amount of hexadecylamine capping ligand and the filling percentage of the autoclave, uniformed-sized MNRs of 4·46nm in diameter and 31·09nm in length were prepared and investigated in terms of their heat-generating ability for application in the MHT and PTT. The experimental results show the good heat-generating ability of the MNRs in both modalities with the maximum absorption rate (SAR) values of 228.51 W/g (MHT) and 56.59 W/g (PTT).

Microwave-Assisted Grafting of Coal onto Nitrogen-Doped Carbon Dots with a High Quantum Yield and Enhanced Photoluminescence Properties.

The fluorescent nitrogen-doped carbon dots (N-CDs) were synthesized via a facile one-pot solvothermal process using coal (Jin 15 Anthracite and Shaerhu lignite) as raw materials and dimethyl formamide (DMF) as the solvent, employing a microwave pyrolysis method. This approach demonstrates remarkable efficacy in the development of nitrogen-doped carbon dots (N-CDs) with a high quantum yield (QY). The N-CDs prepared have strong photoluminescence properties. Moreover, the obtained N-CDs emit blue PL and are easily dispersed in polymethyl methacrylate (PMMA), preserving the inherent advantages of N-CDs and the PMMA matrix. The JN-CDs exhibit a high quantum yield (QY) of 49.5% and a production yield of 25.7%, respectively. In contrast, the SN-CDs demonstrate a quantum yield of 40% and a production yield of 35.1%. It is worth noting that the production yield and quantum yield of coal-based carbon dots are inversely related indices. The lower metamorphic degree of subbituminous coal favors an enhanced product yield, while the higher metamorphic degree of anthracite promotes an improved quantum yield in the product, which may be attributed to the presence of amorphous carbon within it. Consequently, we propose and discuss potential mechanisms underlying N-CD formation.

Impact of tannic acid on iron oxide nanoclusters synthesized by a polyol solvothermal method

Raspberry-shaped iron oxide nanostructures (RSNs) correspond to oriented aggregated and hollow clusters of nanograins exhibiting a high saturation magnetization and a superparamagnetic behaviour. These nanostructures are promising for a wide range of applications, such as magnetic separation, catalysis, pollution control, and nanomedicine. However, for most applications, particularly nanomedecine and depollution, high colloidal stability is required, and the isoelectric point of iron oxide is around 6–7. Therefore, these nanoclusters need to be coated with a surfactant to obtain colloidal suspensions in water. Here, we have developed a one-pot polyol solvothermal synthesis process to coat these promising nanoclusters with tannic acid (TA), a natural compound with antimicrobial properties, which has been little studied with these nanoclusters. Different parameters of the synthesis were adjusted, such as the molar ratio TA:Fe, the synthesis temperature and duration. We showed that TA interferes deeply in the RSNs synthesis mechanism with the observed reduction of iron(III) to iron(II), the complexation of TA with iron, the formation of intermediate phases, as well as the growth of a parasitic iron carbonate phase and the loss of the oriented aggregation and hollowness of the iron oxide RSNs. Considering all these parameters, the optimal synthesis conditions were thus established (TA:Fe ratio = 0.010, temperature of 200°C and duration of 10.5 h), leading to RSNs with small nanograins, a rather high surface area (82 m2/g), high saturation magnetization (74 emu/g) and good colloidal stability. By combining different characterization techniques, a new synthesis mechanism was proposed different from previously established for RSNs without TA, based on strong TA-iron oxide interfaces.

One-pot synthesis of octahedral NiSe2 as a co-catalyst for enhanced CO2 photoreduction performance

Excessive CO2 concentrations in the atmosphere have a range of adverse effects, including climate change and the rise in sea levels. One approach to mitigate these issues is to utilize artificial photosynthesis, which transforms CO2 into valuable fuels. In this study, a unique octahedral nickel selenide (NiSe2) structure supported on one-dimensional (1D) nickel titanate nanofibers (NiTiO3 NFs) was created through a one-pot solvothermal process. The optimized NiTiO3 NFs/NiSe2 nanostructure exhibits exceptional CO2 photoreduction performance across a broader range of the solar spectrum (UV–vis). At a 0.09 wt% NiSe2 concentration, the yields of CH4 and CO were 3.14 and 1.47 times higher, respectively, than those produced by pure NiTiO3 NFs. The exceptional photocatalytic activity can be attributed to the efficient electron extraction and transfer from NiTiO3 NFs to NiSe2, as well as the enhanced light harvesting capacity. Furthermore, the introduction of NiSe2 generates more oxygen vacancies (OV) that can promote the adsorption and activation of CO2 and water, considerably reducing the free energy barrier for COOH* formation and accelerating the reaction kinetics. The results of this study are expected to create new opportunities for synthesizing efficient photocatalysts based on transition metal dichalcogenides that can be utilized in energy conversion applications.

Linker mediated enhancement in reusability and regulation of Pb(II) removal mechanism of Cu-centered MOFs

Our study demonstrates improved hydrolytic stability of Cu-centered MOFs through linker selection, resulting in enhanced and selective Pb(II) removal with contrasting removal mechanisms. A simple one-pot solvothermal process was employed to synthesize Copper 1,3,5-Benzene-Tricarboxylic Acid (Cu-BTC) MOF, Copper Imidazolate (Cu-Im) MOF and Copper Nicotinic Acid (Cu-NA) MOF, respectively. The synthesis of these MOFs was confirmed using characterization techniques such as XPS, XRD, FTIR and ICP-OES. Water stability studies using experimental and modelling approaches demonstrated that substituting the 1,3,5-benzene-tricarboxylic acid linker with either imidazolate or nicotinic acid, enhanced the hydrostability of the Cu-centered MOF from under 2 h to over 48 h, while showing a high Pb(II) adsorption capacity of 492 mg g−1. This improved hydrostability was observed across acidic and basic pH and at elevated temperatures. The improved stability of Cu-Im significantly enhanced its reusability and showed Pb(II) adsorption for 3 cycles, with 99.5 % removal efficiency at the end of the 3rd cycle and a desorption efficiency of 92.7 %. The experimental data obtained were substantiated with modelling studies (density functional theory) to gain insights into the 2D structure of Cu-Im and compare the hydrolytic stability of Cu-BTC and Cu-Im. Cu-Im, when tested on textile effluent showed a Pb(II) removal efficiency of 99 % within 2 h of treatment. This study opens up the possibility of using linker selection and design as a strategy to enhance the hydrostability of Cu-centered MOFs and in the process improve its applicability for environmental remediation applications.

CuBTC Metal-Organic Framework Decorated with FeBTC Nanoparticles with Enhance Water Stability for Environmental Remediation Applications.

Metal-organic frameworks (MOFs) based on Cu-benzene tricarboxylate (CuBTC) are widely used for gas storage and removal applications. However, they readily lose their crystal structures under humid conditions, limiting their practical applications. This structural decomposition reduces the specific surface area, gas adsorption capability, and recyclability of CuBTC considerably. In this study, a stable MOF against water exposure was designed based on FeBTC nanoparticle-covered CuBTC (FeCuBTC). A simple one-pot solvothermal process that enables the epitaxial growth of FeBTC on the CuBTC surface was proposed. Structural and morphological analyses after water exposure revealed that the water stability of FeCuBTC was better than that of CuBTC, which completely lost its crystallinity. This observed improvement in the water stability of the synthesized MOF proved to be beneficial for the adsorption of formaldehyde under humid conditions. The proposed strategy herein is simple yet highly effective in the design of hetero-bimetallic MOFs with considerably improved water resistance and extended applicability for environmental remediation processes.

Effect of carbon-based nanomaterials on the wave absorption properties of hollow ZnFe2O4

Hollow ZnFe2O4/carbon-based nanocomposite absorbers were successfully synthesized using a simple one-pot solvothermal process. Different methods were used to study the physical structure, microstructure, functional groups, and magnetic properties of the composite absorbers. The addition of different carbon-based nanomaterials improves the wave absorption properties in different ways. It not only improves the absorption strength, but also increases the effective absorption bandwidth. According to research findings, a maximum reflection loss of − 37.47 dB was obtained for pure hollow ZnFe2O4 at 1.6 mm, −49.17 dB for ZnFe2O4/rGO at 3.6 mm, −40.31 dB for ZnFe2O4/MWCNTs at 4.8 mm, and − 27.64 dB for ZnFe2O4/MWCNTs/rGO at 1.9 mm. The excellent electromagnetic wave absorption is attributed not only to the magnetic loss of the ferrite and the dielectric loss of the carbon-based nanomaterials, but also to the interfacial polarization between the different materials and the dipolar polarization of the residual functional groups.

Synthesis of magnetic Mn/Fe oxides derived from drinking water sludges from a one-pot solvothermal process for the degradation of tetracycline and mixed dyes: synergistic effect and mechanism study

The development of low-cost, sustainable, and efficient bimetallic nanocomposites is of remarkable importance but it remains a challenge, particularly as many of these composites tend to be synthesized using multiple steps in time-consuming processes. Herein we present a novel MnO/MnFe2O4 heterostructure loaded onto magnetic drinking water sludge (MF-MDWS) nanocomposite via a simple one-pot solvothermal process and evaluation of its catalytic performance at room temperature for the degradation of tetracycline (TC) and mixed dyes. TC was efficiently mineralized (TOC removal of approx. 49.1%) by PMS/MF-MDWS after 30 min of reaction, with a degradation efficiency of 98.3%. In addition, a synergistic factor and reaction stoichiometric efficiency as high as 73.4% and 4.1%, respectively, under conditions of 0.2 g/L MnO/MnFe2O4/SiO2, 10.0 mg/L TC, and 2.0 mM PMS were obtained over a broad pH range (between 3.1 and 9.0). These findings show that MF-MDWS has a synergistic effect, enhancing the chemical reactivity and stability of the catalyst by restricting the agglomeration of nanoparticles, creating Mn-Fe interactions, and promoting mutual electron transfer between Fe and Mn. It was illustrated that the degrading reaction followed pseudo-first-order kinetics and had a low activation energy of 18.9 kJ/mol. Furthermore, the synergic factor, the reaction stoichiometric efficiency, the specific oxidant efficiency, and the oxidant utilization ratio values for the PMS/MF-MDWS system were 73.4%, 5.7%, 0.03% and 87.5%, respectively. To further investigate the generation of the ROS (1O2> SO4•¯ >•OH) and their decontamination pathways, a series of radical quenching tests and electron paramagnetic resonance (EPR) analysis were carried out. In summary, this study systematically evaluated the performance of the PMS/bimetallic nanocomposite system for TC removal with the aim of treating wastewater as industrial waste, thereby laying a theoretical and practical foundation for the treatment of potential antibiotic/mixed dye wastewater on a large or full scale.

The Quick Removal of Toxic Dye Molecules by an Efficient Adsorptive BiOI/Bi2MoO6 Heterostructure

Adsorption is a low-energy, economical, and efficient method for pollutant removal from water. Because of their unique structure, large specific surface area (SSA), and non-toxicity, bismuth-based semiconductors, usually researched for the photodegradation of organic molecules, are also excellent for dark adsorption processes. Here, a three-dimensional adsorbent with a heterostructure with a hydrangea-like shape made of Bi2MoO6 (BMO) and BiOI (BOI) was synthesized by a one-pot solvothermal process and investigated for the adsorption of toxic dyes. BOI/BMO with an I-to-Mo ratio of 2.0 adsorbed 98.9% of the model pollutant rhodamine B (RhB) within 5 min with a maximum adsorption capacity of 72.72 mg/g in the dark at room temperature. When compared to pure BMO, the BOI2/BMO heterostructure was 14.1 times more performant because of its flower-like morphology with multiple planes, an SSA that was 1.6-fold larger, increased porosity, the formation of heterojunctions, and a negative surface charge attracting RhB. Further investigation indicated that adsorption by BOI2/BMO fitted the pseudo-second-order kinetic and the Langmuir isotherm models. In addition, the thermodynamic analysis showed that it was a spontaneous exothermic process probably relying on physisorption. Thus, the BOI/BMO adsorbent developed here is promising for the fast removal of toxic dyes from industrial wastewater.

Systematic Thiol Decoration in a Redox-Active UiO-66-(SH)2 Metal-Organic Framework: A Case Study under Oxidative and Reductive Conditions.

The practical applicability of thiolated metal-organic frameworks (MOFs) remains challenging due to their low crystallinity and transient stability. Herein, we present a one-pot solvothermal synthesis process using varying ratios of 2,5-dimercaptoterephthalic acid (DMBD) and 1,4-benzene dicarboxylic acid (100/0, 75/25, 50/50, 25/75, and 0/100) to prepare stable mixed-linker UiO-66-(SH)2 MOFs (ML-U66SX). For each variant, the effects of different linker ratios on the crystallinity, defectiveness, porosity, and particle size have been discussed in detail. In addition, the impact of modulator concentration on these features has also been described. The stability of ML-U66SX MOFs was investigated under reductive and oxidative chemical conditions. The mixed-linker MOFs were used as sacrificial catalyst supports to highlight the interplay of template stability on the rate of the gold-catalyzed 4-nitrophenol hydrogenation reaction. The release of catalytically active gold nanoclusters originating from the framework collapse decreased with the controlled DMBD proportion, resulting in a 59% drop in the normalized rate constants (9.11-3.73 s-1 mg-1). In addition, post-synthetic oxidation (PSO) was used to further probe the stability of the mixed-linker thiol MOFs under harsh oxidative conditions. Following oxidation, the UiO-66-(SH)2 MOF underwent immediate structural breakdown, unlike other mixed-linker variants. Along with crystallinity, the microporous surface area of the post-synthetically oxidized UiO-66-(SH)2 MOF could be increased from 0 to 739 m2 g-1. Thus, the present study delineates a mixed-linker strategy to stabilize the UiO-66-(SH)2 MOF under harsh chemical conditions through meticulous thiol decoration.

Polyhedral MnSe microparticles with specific Hg2+-suppressed oxidase-like activity: Toward a green and low-cost turn-off method for Hg2+ detection

With the attractive advantage of catalytic signal amplification, noble metal-based peroxidase-mimicking nanomaterials have been intensively used to establish optical methods for hypertoxic Hg2+ detection. However, in these methods the requirement of high-concentration H2O2 can lead to secondary pollution, and the noble metals used result in these assays’ high cost. Therefore, exploring new categories of enzyme mimics to develop environmentally friendly and low-cost approaches for Hg2+ sensing is highly desired. Herein we proposed a novel noble metal-free material, MnSe microparticles, featuring specific Hg2+-suppressed oxidase-like catalytic activity, to fabricate a green, cheap, and high-performance turn-off approach for Hg2+ detection. The MnSe microparticles with a polyhedral structure were obtained via a one-pot solvothermal process, showing excellent oxidase-like activity to catalyze the oxidation of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to its blue product. The introduction of Hg2+ can significantly mask their active sites via forming an inert layer of HgSe outside the MnSe microparticles, thus suppressing the TMB catalytic color reaction. Based on the turn-off principle, colorimetric quantification of Hg2+ was realized with high sensitivity and specificity. By integrating smartphone sensing with 3D-printed accessories and paper strips, a portable platform for the convenient detection of Hg2+ was further established, demonstrating its great practicability in real analysis.

Facile Strategy for Fabricating an Organosilica-Modified Fe3O4 (OS/Fe3O4) Hetero-nanocore and OS/Fe3O4@SiO2 Core-Shell Structure for Wastewater Treatment with Promising Recyclable Efficiency.

The development of a sustainable process for heavy metal ion remediation has become a point of interest in various fields of research, including wastewater treatment, industrial development, and health and environmental safety. In the present study, a promising sustainable adsorbent was fabricated through continuous controlled adsorption/desorption processes for heavy metal uptake. The fabrication strategy is based on a simple modification of Fe3O4 magnetic nanoparticles with organosilica in a one-pot solvothermal process, carried out in order to insert the organosilica moieties into the Fe3O4 nanocore during their formation. The developed organosilica-modified Fe3O4 hetero-nanocores had hydrophilic citrate moieties, together with hydrophobic organosilica ones, on their surfaces, which facilitated the further surface coating procedures. To prevent the formed nanoparticles from leaching into the acidic medium, a dense silica layer was coated on the fabricated organosilica/Fe3O4 (OS/Fe3O4). In addition, the prepared OS/Fe3O4@SiO2 was utilized for the adsorption of cobalt(II), lead(II), and manganese(II) from the solutions. The data for the adsorption processes of cobalt(II), lead(II), and manganese(II) on OS/(Fe3O4)@SiO2 were found to follow the pseudo-second-order kinetic model, indicating the fast uptake of heavy metals. The Freundlich isotherm was found to be more suitable for describing the uptake of heavy metals by OS/Fe3O4@SiO2 nanoparticles. The negative values of the ΔG° showed a spontaneous adsorption process of a physical nature. The super-regeneration and recycling capacities of the OS/Fe3O4@SiO2 were achieved, comparing the results to those of previous adsorbents, with a recyclable efficiency of 91% up to the seventh cycle, which is promising for environmental sustainability.

One-Step Solvothermal Synthesis by Ethylene Glycol to Produce N-rGO for Supercapacitor Applications.

Graphene and its derivatives have emerged as peerless electrode materials for energy storage applications due to their exclusive electroactive properties such as high chemical stability, wettability, high electrical conductivity, and high specific surface area. However, electrodes from graphene-based composites are still facing some substantial challenges to meet current energy demands. Here, we applied one-pot facile solvothermal synthesis to produce nitrogen-doped reduced graphene oxide (N-rGO) nanoparticles using an organic solvent, ethylene glycol (EG), and introduced its application in supercapacitors. Electrochemical analysis was conducted to assess the performance using a multi-channel electrochemical workstation. The N-rGO-based electrode demonstrates the highest specific capacitance of 420 F g-1 at 1 A g-1 current density in 3 M KOH electrolyte with the value of energy (28.60 Whkg-1) and power (460 Wkg-1) densities. Furthermore, a high capacitance retention of 98.5% after 3000 charge/discharge cycles was recorded at 10 A g-1. This one-pot facile solvothermal synthetic process is expected to be an efficient technique to design electrodes rationally for next-generation supercapacitors.

Mn-doped FeS with larger lattice spacing as advance anode for sodium ion half/full battery

Owing to their high theoretical capacity, transition metal sulfides are appearing as reliable electrode materials for sodium ion batteries (SIBs), but achieving both high capacity and enduring cyclic stability remain a serious challenge. Here, multi-core Mn-doped FeS/NC was synthesized by one-pot solvothermal and annealing process. Larger lattice spacing, inducing by doping Mn-atoms, provides more space to store sodium ions. The doping of Mn-atoms increases the conductivity, enhancing the transport of charge carrier and rate performance. Multi-core structure and attached carbon can improve tolerance of volume expansion, which is beneficial to the long-term cyclic performance. In addition, it is also proved by density functional theory (DFT) that Mn-doping FeS can enhance the conductivity and lattice spacing. As a result, Mn-doped FeS/NC delivers high reversible capacity (563.3 mAh·g−1 at 0.5 A·g−1), excellent rate capability (442.8 mAh·g−1 at 8 A·g−1) and enduring cyclic stability (206.2 mAh·g−1 after 8000 cycles) as an anode for SIBs. Specially, a cathode of Na3V2(PO4)3/C is paired with the anode of Mn-doped FeS/NC to assembled into a full battery, showing a highly energy density (281.4 Wh·kg−1 at a power density 625.3 W·kg−1) and capacity retention rate. The present work provide a promise strategy to improve electrochemical performance of the monometallic sulfide.

Oxygen vacancy triggering the broad-spectrum photocatalysis of bismuth oxyhalide solid solution for ciprofloxacin removal

The construction of a broad-spectrum photocatalytic system is of great significance for maximizing the utilization of solar energy. Herein, a surface oxygen vacancy triggering high-efficient broad-spectrum BiOCl0.5I0.5 solid solution photocatalyst was successfully fabricated via a one-pot solvothermal process. The UV–vis diffuse reflectance spectra revealed that the introduced oxygen vacancy appears to extend the absorption region of BiOCl0.5I0.5 to a wider wavelength range. Under λ > 580 nm light irradiation for 5 h, nearly 85.6% ciprofloxacin was degraded by BiOCl0.5I0.5 with rich oxygen vacancy, the ciprofloxacin removal efficiency was 3.4 times higher than that with less oxygen vacancy. Moreover, the density functional theory calculations and photoelectrochemical characterizations indicated the excited electrons would preferentially transfer to the new defect level induced by oxygen vacancy, thus greatly reducing the recombination of photogenerated carriers. This work tends to deepen the understanding of defect engineering in steering the construction of broad-spectrum Bi-based solid solution photocatalysts as well as its application in environmental remediation.

Ultrafast hydrogenation of magnesium enabled by tetragonal ZrO2 hierarchical nanoparticles

Transition metal catalysts are particularly effective in improving the reaction kinetics of light metal hydrides for reversible hydrogen storage. Herein, tetragonal ZrO2 hierarchical nanoparticles (nano-ZrO2) composed of primary particles of ∼4 nm in diameter are successfully synthesized by a facile one-pot solvothermal process. The unique hierarchical structure features homogeneous distributions of in situ formed multivalent Zr-based species, which allow superior catalytic activity for hydrogen storage in MgH2. The MgH2+10 wt% nano-ZrO2 starts releasing H2 at 163 °C after one activation, which is 107 °C lower than additive-free MgH2, and 50 °C lower than that of bulk ZrO2-doped MgH2. At 230 °C, 5.9 wt% of H is rapidly liberated within 20 min from the nano-ZrO2-containing MgH2. More importantly, the material shows superior hydrogenation kinetics compared with all reported catalyst-modified MgH2. The nano-ZrO2-containing Mg took up 4.0 wt% of H in only 12 s at 100 °C under 50 bar H2, 400 times faster than the bulk-ZrO2-modified sample. Even at 50 °C, approximately 1.8 wt% H was absorbed within 1 min. Our findings provide useful insights into the design and development of high-performance catalysts toward solid-state hydrogen storage materials.

One-Pot Synthesis of Magnetoplasmonic Au@FexOy Nanowires: Bioinspired Bouligand Chiral Stack.

One-dimensional hybrid nanostructures composed of a plasmonic gold nanowire core covered by a shell of magnetic oxide nanoparticles (Au@FexOy NWs) were synthesized by a one-pot solvothermal synthesis process. The effects of reaction temperature, time, reducing agent, and precursor as well as postsynthesis treatment were optimized to produce highly uniform NWs with a diameter of 226 ± 25 nm and a plasmonic core aspect ratio of 25 to 82. By exploiting the interaction of NWs with an external magnetic field, precise arrangements into highly periodic photonic structures were achieved, which can generate distinctive structural colors that are vividly iridescent and polarization-sensitive. Furthermore, a Bouligand-type chiral nematic film consisting of multistacked unidirectional layers of achiral NWs was fabricated using a modified layer-by-layer deposition method, which displays circular dichroism (CD) and chiral sensing capability. The addition of bovine serum albumin (BSA) as a model protein analyte induced a concentration-dependent wavelength shift of CD peaks. These intriguing properties of magnetoplasmonic anisotropic NWs and their self-assemblies could be consequently valuable for developing nature-inspired structural color imprints as well as solid-state chiral sensing devices.