Search

Glycerol is a byproduct of biodiesel production. Selective photoelectrochemical oxidation of glycerol to high value‐added chemicals offers an economical and sustainable approach to transform renewable feedstock as well as store green energy at the same time. In this work, we synthesized monoclinic WO3 nanosheets with exposed (002) facets, which could selectively oxidize glycerol to glyceric acid (GLYA) with a photocurrent density of 1.7 mA cm−2, a 73 % GLYA selectivity and a 39 % GLYA Faradaic efficiency at 0.9 V vs. reversible hydrogen electrode (RHE) under AM 1.5G illumination (100 mW cm−2). Compared to (200) facets exposed WO3, a combination of experiments and theoretical calculations indicates that the superior performance of selective glycerol oxidation mainly originates from the better charge separation and prolonged carrier lifetime resulted from the plenty of surface trapping states, lower energy barrier of the glycerol‐to‐GLYA reaction pathway, more abundant active sites and stronger oxidative ability of photogenerated holes on the (002) facets exposed WO3. Our findings show great potential to significantly contribute to the sustainable and environmentally friendly chemical processes via designing high performance photoelectrochemical cell via facet engineering for renewable feedstock transformation. [ABSTRACT FROM AUTHOR]

Herein, a scalable electrodeposition strategy is proposed to achieve hierarchical CuO/nickel–cobalt–sulfide (NCS) electrodes using two-step potentiostatic deposition followed by high-temperature calcination. The introduction of CuO provides support for the further deposition of NSC to ensure a high load of active electrode materials, thus generating more abundant active electrochemical sites. Meanwhile, dense deposited NSC nanosheets are connected to each other to form many chambers. Such a hierarchical electrode prompts a smooth and orderly transmission channel for electron transport, and reserves space for possible volume expansion during the electrochemical test process. As a result, the CuO/NCS electrode exhibits superior specific capacitance (Cs) of 4.26 F cm−2 at 20 mA cm−2 and remarkable coulombic efficiency of 96.37%. Furthermore, the cycle stability of the CuO/NCS electrode remains at 83.05% within 5000 cycles. The multistep electrodeposition strategy provides a basis and reference for the rational design of hierarchical electrodes to be applied in the field of energy storage. [ABSTRACT FROM AUTHOR]

ZnIn2S4 is a promising candidate for photocatalysis. However, it is still facing great challenge to improve its photocatalytic activity through rationally regulating its microstructures. Herein, ZnIn2S4 micro-flowers with different self-assembly microstructures were synthesized by solvent induced through one-step hydrothermal method, and were used as catalytic dehydrogenation of 1,2,3,4-tetrahydroisoquinoline to 3,4-dihydroisoquinolines. Different solvents have great effects on the microstructure of ZnIn2S4. The surface of ZIS-H2O petals is relatively smooth, and the petals of ZIS-EtOH are micro-discoid and relatively rough. The microstructure of ZIS-EG is the smallest and consists of countless irregular thin nanosheet. The results show that ZIS-EG assembled with ethylene glycol as solvent has the best photocatalytic activity in the catalytic dehydrogenation. The maximum conversion of 98% as well as the selectivity of 99% of 3,4-dihydroisoquinolines was accomplished under air condition with 7-h visible-light irradiation. The excellent photocatalytic activity of ZIS-EG benefits from its excellent absorption of visible light as well as the separation efficiency of photogenerated carriers. Therefore, this work has provided an effectively method to accelerate the photocatalytic activity through solvent-induced controlling microstructures. A series of ZnIn2S4 photocatalysts with different microscopic morphologies were synthesized, and were used as catalytic dehydrogenation of 1, 2, 3, 4-tetrahydroisoquinoline to 3, 4-dihydroisoquinolines. The results show that ZnIn2S4 synthesized in ethylene glycol solvent has the best photocatalytic dehydrogenation activity. [ABSTRACT FROM AUTHOR]

Multipores engineering composed of micro/mesopores is an effective strategy to improve potassium storage performance via providing enormous adsorption sites and shortened ions diffusion distance. However, a detailed exploration of the role played by macropores in potassium storage is still lacking and has been barely reported until now. Herein, a superstructure carbon hexahedron (DGN‐900) is synthesized using poly tannic acid (PTA) as precursor. Due to the spatially confined two‐step local contraction of PTA along different directions and dimensions during pyrolysis, defective nanosheets with macropores are formed, while realizing a balance between defects content and graphitization degree by regulating temperature. The presence of macropores is conducive to accelerating electrolyte ions rapid infiltration within electrode, and its pore volume can accommodate electrode structure fluctuation upon cycling, while the most suitable ratio of defects to graphitic provides rich ions adsorption sites and sufficient electrons transfer channels, simultaneously. These advantages enable a prominent electrochemical performance in DGN‐900 electrode, including high rate (202.9 mAh g−1 at 2 A g−1) and long cycling stability over 2000 cycles. This unique fabrication strategy, that is, defects engineering coupled with macropores structure, makes fast and durable potassium storage possible. [ABSTRACT FROM AUTHOR]

Porous nanomaterials have attracted much attention in the field of electrochemiluminescence (ECL) analysis research because of their large specific surface area, high porosity, possession of multiple functional groups, and ease of modification. Porous nanomaterials can not only serve as good carriers for loading ECL luminophores to prepare nanomaterials with excellent luminescence properties, but they also have a good electrical conductivity to facilitate charge transfer and substance exchange between electrode surfaces and solutions. In particular, some porous nanomaterials with special functional groups or centered on metals even possess excellent catalytic properties that can enhance the ECL response of the system. ECL composites prepared based on porous nanomaterials have a wide range of applications in the field of ECL biosensors due to their extraordinary ECL response. In this paper, we reviewed recent research advances in various porous nanomaterials commonly used to fabricate ECL biosensors, such as ordered mesoporous silica (OMS), metal–organic frameworks (MOFs), covalent organic frameworks (COFs) and metal–polydopamine frameworks (MPFs). Their applications in the detection of heavy metal ions, small molecules, proteins and nucleic acids are also summarized. The challenges and prospects of constructing ECL biosensors based on porous nanomaterials are further discussed. We hope that this review will provide the reader with a comprehensive understanding of the development of porous nanomaterial-based ECL systems in analytical biosensors and materials science. [ABSTRACT FROM AUTHOR]

In this work, a composite photocatalyst consisted of the porous graphitic carbon nitride (pg‐C3N4) nanosheets decorated with in‐situ grown gold (Au) nanoparticles were prepared. By characterizing and analyzing chemical compositions and structures, and optical and electrical properties of this Au/pg‐C3N4 composite, the excellent photocatalytic performance mainly comes from the following aspects: firstly, pg‐C3N4 synthesized from melamine by high‐temperature calcination with the assistance of ascorbic acid has larger specific surface area and narrower band gap width than common g‐C3N4; secondly, localized surface plasmon resonance (LSPR) effect of Au nanoparticles can enhance light absorption of pg‐C3N4 via near‐field enhancement‐induced excitation; thirdly, the heterojunction formed between Au nanoparticles and pg‐C3N4 nanosheets can promote electron transfer. Consequently, Au/pg‐C3N4 presented the obvious improvement of photocatalytic activity on the degradation of rhodamine B and amaranth under simulated solar irradiation that the kinetic rate constant of degradation reaction can be increased by 3.9 and 5.7 times compared with g‐C3N4, respectively. [ABSTRACT FROM AUTHOR]

The synthesis of carbamates by electrocatalytic reduction of CO2 is an effective method to realize the utilization of CO2 resources. The development of high‐performance electrocatalysts to complete this process more efficiently is of great significance to sustainable development. Owing to their unique structural characteristics, single‐atom catalysts are expected to promote the reaction process more efficiently. In this study, an atomically dispersed Cu species on N‐doped carbon nanosheet composite material (Cu−N−C) was prepared by metal‐organic framework derivatization. Compared with traditional Cu bulk electrodes, the Cu−N−C material has better catalytic performance for the synthesis of methyl N‐phenylcarbamate; and the optimized yield reached 71 % at room temperature and normal pressure. The Cu−N−C material has good stability that the catalytic performance does not decrease after repeated use for 10 times. In addition, the Cu−N−C material has good applicability to this catalytic system, and a variety of amines can be smoothly converted into corresponding carbamates. [ABSTRACT FROM AUTHOR]

The multifunctional photocatalysts (Au-Pd/SnNb 2 O 6 ultrathin nanosheets) are developed for selective hydrogenation of cinnamaldehyde to hydrocinnamaldehyde under visible light. The superior catalytic performance is attributed to a synergistic effect of Au, Pd nanoparticles, and SnNb 2 O 6 ultrathin nanosheets. [Display omitted] • Au-Pd/SnNb 2 O 6 (SN) as photocatalysts for selective hydrogenation of cinnamaldehyde. • The C = C of cinnamaldehyde would be absorbed on the surface Lewis acid sites of SN. • Photogenerated electrons promoted H 2 dissociation on Pd, Au reduced overhydrogenation. • The superior performance is attributed to a synergistic effect of catalyst component. Au-Pd bimetallic nanoparticles (NPs) supported on SnNb 2 O 6 ultrathin nanosheets (SN) were developed as multifunctional photocatalysts for the selective hydrogenation of cinnamaldehyde (CAL) to hydrocinnamaldehyde (HCAL) under visible light irradiation. A representative catalyst (Au 6 -Pd 1 /SN) exhibits optimum performances with 99.8% conversion and 91.0% selectivity. The structure and surface properties of the prepared samples were revealed by SEM, TEM, BET, TPD, XPS, and EPR. The results of in situ FTIR spectra and NH 3 -TPD reveal that the rich surface Lewis acid sites on SN can chemisorb and activate CAL via the C = C...Nb coordination. EPR experiments indicate that H 2 would dissociate to activated H atoms on Pd NPs following a photopromoted surface catalytic process. Experimental results suggest that Au NPs reduce the over hydrogenation of HCAL by inhibiting the formation of Pd-H species. The superior catalytic performance is attributed to a synergistic effect of Au, Pd NPs and SN. Finally, a possible synergetic mechanism for Au-Pd/SN is proposed to illustrate the photocatalytic process. This work offers a reference to guide a novel and more effective photocatalyst design for precise organic synthesis driven by sunlight. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Uniform silver nanowires (AgNWs) with high aspect ratio are significant to fabricate high-performance transparent conductive films (TCFs). In this work, AgNWs were synthesized through polyol method using AgCl as seeds. The growth mechanism of AgNWs upon AgCl particles was demonstrated, which provided a clear understanding of heterogeneous nucleation for synthesizing crystal. The amounts and the reaction time of AgCl were discussed to probe the effect on morphology of final AgNWs. Apart from that, the temperature was also tuned to provide appropriate thermal energy for synthesis of AgNWs. Uniform AgNWs with thin diameter about 52 nm and aspect ratio above 1000 were synthesized by optimizing the amounts, reaction time of AgCl and the temperature. These AgNWs were utilized to fabricate TCFs firstly through spin-coating at a variable speed. The resulting films coated at variable spin-speed largely improved the performance of films compared with those of films coated at constant spin-speed, exhibiting a low sheet resistance of 54 Ω sq−1 and high transmittance of 92% at 550 nm with haze of 5.4%. [ABSTRACT FROM AUTHOR]

Ca-doped BiFeO3 nanofibres have been fabricated by electrospinning method. Our results indicate that phase transition from space group R3c to C222 can be observed by the Ca doping. These BiFeO3 nanofibres show obvious room temperature ferromagnetic behaviors, and saturation magnetization can be enhanced with the Ca-doping concentration increasing, which could be correlated with the variation of the ratio of Fe2+/Fe3+ valence state. The BiFeO3 nanofibres show obvious photocatalytic performance and can be improved by the Ca-doping. [ABSTRACT FROM AUTHOR]

Direct light-to-work conversion enables manipulating remote devices in a contactless, controllable, and continuous manner. Although some pioneering works have already proven the feasibility of controlling devices through light-irradiation-induced surface tension gradients, challenges remain, including the flexible integration of efficient photothermal materials, multifunctional structure design, and fluidic drag reduction. This paper reports a facile one-step method for preparing light-driven floating devices with functional surfaces for both light absorption and drag reduction. The direct laser writing technique is employed for both arbitrary patterning and surface modification. By integrating the functional layer at the desired position or by designing asymmetric structures, three typical light-driven floating devices with fast linear or rotational motions are demonstrated. Furthermore, these devices can be driven by a variety of light sources including sunlight, a filament lamp, or laser beams. The approach provides a simple, green, and cost-effective strategy for building functional floating devices and smart light-driven actuators. [ABSTRACT FROM AUTHOR]

In this study, a Schottky-type ultraviolet (UV) photodetector based on double-layered nanostructured TiO 2 /Au films was fabricated. Double-layered titanium dioxide (TiO 2 ) nanostructures composed of one layer of TiO 2 nano-flowers on one layer of TiO 2 nanorods on fluorine-doped tin oxide (FTO) pre-coated glass substrates were synthesized via a convenient hydrothermal method using titanium butoxide and hydrochloric acid as the starting precursor, without involving the use of any other surfactants and catalysts. A granular-shaped thin-layer of Au film using vacuum sputter coating technique was subsequently deposited on TiO 2 for the formation of Schottky-type photodetector. The as-fabricated Schottky device showed various photocurrent responses when irradiated with different wavelength of UV light. This suggests that the newly-developed photodetectors have promising potential for identifying different UV light wavelengths. [ABSTRACT FROM AUTHOR]

Advances in synthesis and processing of nanocarbon materials particularly carbon nanotubes and graphene have presented the opportunity to design novel Li-ion battery (LIB) anode materials that can meet the power requirements of next-generation power devices. This mini-review presents an overview of recent studies on the electrochemical behavior of three-dimensional (3D) nanostructured anode materials formed by coupling graphene sheets with alloying type active materials (metals or metal oxides). A number of promising 3D graphene-based hybrid anodes ranging from sheet-like, core-shaped, to foam-like morphologies are discussed. The significant improvement observed in the LIB performance of the 3D hybrid anodes is largely attributed to the unique properties of graphene and the resulting 3D architecture. [ABSTRACT FROM AUTHOR]

Surface Engineering Improving Selective Hydrogenation of p -Chloronitrobenzene over AuPt alloy/SnNb 2 O 6 ultrathin nanosheets under Visible light. [Display omitted] • Bimetallic alloy AuPt decorated SnNb 2 O 6 nanosheet (AuPt/SN) as a photocatalyst has been constructed successfully. • The catalyst (Au 0.5 Pt 0.5 /SN) exhibits a high catalytic conversion efficiency for p -chloronitrobenzene (99.8%) with a selectivity of p -chloroaniline (99.1%). • SN could activate p -chloronitrobenzene via a Sn2+···–NO 2 coordination. • A synergetic effect among Lewis base sites (Sn2+), AuPt alloy and photogenerated electrons is proposed. • A photocatalytic mechanism is determined at molecule scale. AuPt alloy/SnNb 2 O 6 ultrathin nanosheet (AuPt/SN) as a photocatalyst is constructed for selective hydrogenation of p -chloronitrobenzene (p -CNB) under visible light irradiation. A typical catalyst (Au 0.5 Pt 0.5 /SN) exhibits a high conversion of halonitrobenzenes (99.8%) and selectivity of haloaniline (99.1%). The results of in situ ATR-IR, XPS and Raman indicate a preferential chemoselective adsorption of –NO 2 that Lewis base sites (Sn2+) on the catalyst could selectively coordinate with –NO 2 whereas C-Cl bond is not be bonded, improving the catalytic selectivity. Atom Pt in alloy is responsible for the formation of ·H, while Au inhabits the dissociation of C-Cl via repressing the generation of Pt-H. The photogenerated electrons can accelerate the ·H formation. ·H could be transferred to Sn2+ sites for the hydrogenation of –NO 2 by hydrogen spillover. Therefore, the high performance of the catalyst can be attributed to a surface synergetic effect among Lewis base sites (Sn2+), AuPt alloy and photogenerated electrons. [ABSTRACT FROM AUTHOR]

By employing dopamine as a nitrogen source and reducing agent, the block copolymer P123 as a pore forming agent, and graphene oxide as a carbon precursor, we present, for the first time, a convenient and controllable approach to the preparation of a novel uniformly nitrogen doped porous graphene (N-PGR) material. Using the prepared N-PGR as the supporting material, a novel nitrogen doped porous graphene/Pt nanoflower material (Pt/N-PGR) was obtained by a green and simple method. The characterization results of scanning electron microscopy (SEM), element mapping, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) demonstrate that Pt nanoflowers are uniformly dispersed on nitrogen doped porous graphene. Electrochemical measurements show that Pt/N-PGR-900/GCE exhibits improved electrocatalytic activity towards H2O2 reduction and glucose oxidation. Linear responses are found for H2O2 and glucose in the range of 0.5–40 326 μM and 0.5–133.5 mM with the detection limit (S/N = 3) of 0.2 μM and 0.05 mM, respectively. In addition, Pt/N-PGR-900/GCE exhibits high sensitivity and good anti-interference ability. The superior catalytic activity and selectivity make Pt/N-PGR a promising nanomaterial for application in electrochemical biosensing studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu 3 Pd 1 /SN exhibits a high performance for semihydrogenation of phenylacetylene. • Cu 3 Pd 1 /SN could activate phenylacetylene via C≡C → Nb π-bonded coordination. • The photogenerated electrons facilitate the production of active H. Bimetallic alloy of CuPd nanoclusters decorated SnNb 2 O 6 nanosheet (CuPd/SN) as a multifunctional photocatalyst has been constructed successfully. Compared with SN, CuPd/SN achieves an excellent performance for semihydrogenation of phenylacetylene under visible light irradiation. Especially, CuPd/SN with the Cu:Pd molar ratio of 3:1 exhibits the highest catalytic conversion efficiency for phenylacetylene (99.6%) with high selectivity of phenylethylene (99.4%). In situ FTIR result reveals that SN could activate phenylacetylene via a C≡C → Nb π-bonded coordination which improves the selectivity of phenylethylene. Experiment results indicate that atom Pd in alloy is responsible for dissociation H 2 , while Cu represses the overhydrogenation. Electrochemical measurements suggest that CuPd alloy on SN surface could greatly minimize the recombination of photogenerated electron − hole pairs. The separated electrons further facilitate the production of active H. Hydrogen spillover would transfer active H to Nb site for phenylacetylene semihydrogenation. Finally, a synergetic catalytic mechanism is deeply discussed at molecule scale. This work would provide a deep insight for designing a multifunctional photocatalyst. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, using copper as an etching agent, a novel and easy method to prepare porous graphene nanosheet (P-GR) was reported. With a large number of pores, more acidic groups and edge defect sites (EDSs) compared with graphene (GR), the prepared P-GR was used as an electrochemical biosensing platform for the first time. Using voltammetry and amperometry as detection methods, some important electroactive compounds, including dopamine (DA), ascorbic acid (AA), uric acid (UA), epinephrine (EP), guanine (G), adenine (A), xanthine (XA), hypoxanthine (HX), hydrogen peroxide and β-nicotinamide adenine dinucleotide (NADH) were employed to study their electrochemical responses on P-GR modified glassy carbon electrode (P-GR/GCE). The results show that P-GR/GCE exhibits better electrochemical performance to these substances compared with GR modified glassy carbon electrode (GR/GCE) and edge plane pyrolitic graphite electrode (PGE). The remarkable electrochemical advantage of P-GR makes it a promising material in electrochemical biosensing field. [Copyright &y& Elsevier]

Abstract: Three different kinds of highly ordered mesoporous carbon (HMC) matrices with different morphologies (hexagonal, spherical and fibrous), particle sizes (700nm, 400–900nm and 1–4μm) and pore diameters were compared as drug carriers for a model drug, simvastatin (SIM). The physicochemical properties of the SIM-loaded composites were studied using field emission scanning electron microscopy (FESEM), specific surface area analysis, differential scanning calorimetry (DSC), wide-angle X-ray scattering (WAXS), HPLC, solubility measurement and dissolution testing. Furthermore, the oral bioavailability of SIM-loaded SHMC (spherical HMC nanomatrix) in beagle dogs was compared with that of the reference formulation (Zocor®). The results obtained showed that SIM molecules are encapsulated in a noncrystalline state due to geometric confinement in the nanopores of HMC. In vitro dissolution testing showed that the dissolution rate of SIM released from monodispersed SHMC was significantly faster compared with that of crystalline SIM and other SIM-loaded composites. In addition, in vivo bioavailability study demonstrated that the relative bioavailability of SIM and SIM β-hydroxy acid (an active metabolite of SIM) for SIM-loaded SHMC formulation was 138.42% and 163.55%, respectively. In conclusion, monodispersed SHMC appear to be a more promising candidate as a new oral drug delivery vehicle providing a rapid drug release and enhanced oral bioavailability. [Copyright &y& Elsevier]

[Display omitted] • The P3HT nanosheets decorated TiO 2 nanorod arrays is fabricated. • The photoelectrode shows good charge separation performance. • The photoelectrode shows enhanced photoelectrocatalytic degradation for organic pollutant. TiO 2 /P3HT photoelectrodes were prepared by hydrothermal method followed with a dip-coating method. The solar response range of TiO 2 /P3HT is broadened from 410 nm to 650 nm. The photocurrent of TiO 2 /P3HT-3 photoelectrode is 2 times of TiO 2. The degradation of bisphenol A (BPA) over TiO 2 /P3HT-3 photoelectrode is 15% higher than TiO 2. Besides, A synergetic effect of photoelectrocatalysis (PEC) was attained over TiO 2 /P3HT composite photoelectrode. Moreover, the composite photoelectrode has good stability. [ABSTRACT FROM AUTHOR]

Electrocrystallization of nanoneedles and nanorods of silver-tetracyanoquinodimethane (AgTCNQ) onto a gold substrate has been achieved from the ionic liquid, 1-n-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4), containing dissolved TCNQ and Ag+. In ionic liquid media, underpotential deposition (UPD) and overpotential deposition (OPD) of metallic Ag at a gold electrode occur at more positive potentials than that for reduction of TCNQ to TCNQ−. In contrast, the reduction of TCNQ and Ag+occurs at almost the same potential in MeCN. The different thermodynamics that apply in the ionic liquid environment enables controlled electrocrystallization of AgTCNQ viapotential-dependent mechanisms. Nanoneedles AgTCNQ could be obtained at 0.3 V vs.Fc0/+(Fc = ferrocene), while nanorods could be formed at −0.2 V vs.Fc0/+. Raman, IR and X-ray diffraction data imply that the formation of highly pure and crystalline phase of AgTCNQ on gold, and that AgTCNQ electrocrystallized under UPD or OPD conditions only differ in morphology and not in phase. The study highlights the capability of the electrocrystallization method to precisely control the morphology of nanomaterials, and also using ionic liquids as media for preparation of technologically important metal-TCNQ charge transfer complexes. [ABSTRACT FROM AUTHOR]

Differential scanning calorimetry (DSC) and transmission electron microscopy (TEM) are employed to investigate the crystallization behavior in metallic Zr70Cu20Ni10 glass during continuous heating. It is found that the DSC curves of metallic Zr70Cu20Ni10 glass exhibit two exothermic peaks, indicating that the crystallization process proceeds via a double stage mode. TEM microstructural analysis confirms that the first exothermic reaction in the DSC traces of metallic Zr70Cu20Ni10 glass mainly corresponds to the precipitation of the Zr2Cu phase, while the second one corresponds to the formation of nano-scale Zr2Ni particles. Ni plays an important role in the stability of the nanocrystals, and its effect is also discussed. [Copyright &y& Elsevier]

Carbamates, carbon dioxide, copper, electrocatalysis, single-atom catalysts Cover Feature: Atomically Dispersed Copper on N-Doped Carbon Nanosheets for Electrocatalytic Synthesis of Carbamates from CO2 as a C1 Source (ChemSusChem 9/2021) Keywords: carbamates; carbon dioxide; copper; electrocatalysis; single-atom catalysts EN carbamates carbon dioxide copper electrocatalysis single-atom catalysts 1971 1971 1 05/08/21 20210506 NES 210506 B The Cover Feature b shows an atomically dispersed Cu species on N-doped carbon nanosheet composite material for electrocatalytic synthesis of carbamates using CO SB 2 sb under mild conditions. [Extracted from the article]

Trenbolone (TB) is used for treating malnutrition in livestock and increasing their muscle mass. However, its excessive intake can lead to metabolic and reproductive disorders in animals. In addition, it causes adverse effects in humans even at very low concentrations. Herein, an innovative electrochemiluminescence (ECL) immunosensor based on a double-assisted signal amplification strategy has been proposed for the sensitive detection of TB. Nb 2 O 5 -decorated TiO 2 nanorods, with a large surface area, good biocompatibility, and excellent catalytic properties, were used as the substrates for the effective loading of TB antibodies. In addition, Co 3 O 4 -Co 3 (PO 4) 2 nanosheets, used as labels, improved the ECL signals and were used to incorporate TB antigens for designing competitive ECL immunosensors. Various experimental factors, such as the pH of the phosphate buffer solution, concentration of the co-reactant, and time of incubation, were examined. The proposed ECL immunosensor exhibited high sensitivity, good repeatability, and high stability for TB concentration and was successfully implemented for the analysis of real water samples. Under optimal conditions, the proposed immunosensor responded linearly to relevant concentrations of TB from 1.0 × 10−3 to 1.0 × 103 ng/mL, with a detection limit of 0.39 × 10−3 ng/mL (S/N = 3). Notably, this study fabricated a simple and ultrasensitive TB detection system with novelty of practical application in environmental monitoring. • This work proposed double-assisted signal amplification strategy due to synergistic effect of Nb 2 O 5 -TiO 2 and Co 3 O 4 -Co 3 (PO 4) 2. • The fabricated ECL immunosensor exhibits excellent selectivity and sensitivity towards TB detection. • TB was detected with LOD low as 0.39 × 10−3 ng/mL along with effective environmental applications. [ABSTRACT FROM AUTHOR]

Room‐temperature (RT) sodium–sulfur (Na–S) batteries are attractive cost‐effective platforms as the next‐generation energy storage systems by using all earth‐abundant resources as electrode materials. However, the slow kinetics of Na–S chemistry makes it hard to achieve high‐rate performance. Herein, a facile and scalable approach has been developed to synthesize hollow sodium sulfide (Na2S) nanospheres embedded in a highly hierarchical and spongy conductive carbon matrix, forming an intriguing architecture similar to the morphology of frogspawn coral, which has shown great potential as a cathode for high‐rate performance RT Na–S batteries. The shortened Na‐ion diffusion pathway benefits from the hollow structures together with the fast electron transfer from the carbon matrix contributes to high electrochemical reactivity, leading to superior electrochemical performance at various current rates. At high current densities of 1.4 and 2.1 A g−1, high initial discharge capacities of 980 and 790 mAh g−1sulfur can be achieved, respectively, with reversible capacities stabilized at 600 and 400 mAh g−1sulfur after 100 cycles. As a proof of concept, a Na‐metal‐free Na–S battery is demonstrated by pairing the hollow Na2S cathode with tin‐based anode. This work provides guidance on rational materials design towards the success of RT high‐rate Na–S batteries. Frogspawn‐coral‐like hollow Na2S nanospheres embedded in a carbon matrix are synthesized and serve as a high‐rate performance cathode for Na–S batteries. This highly hierarchical structure significantly promotes Na–S electrochemical activity, contributing to a superior electrochemical performance at high current densities. By using this Na2S cathode with fully‐sodiated state, a Na‐metal‐free Na–S battery is demonstrated. [ABSTRACT FROM AUTHOR]

Through a facile and efficient method, Ni nanoparticles were uniformly embedded into nanoporous carbon nanorods (Ni-NCN), which are subsequently electrodeposited on CoFe-layered double hydroxide (LDH) nanosheets to produce highly efficient Ni-NCN/CoFe-LDH composites used for OER. [Display omitted] • CoFe-LDH directly grew on Ni-NCN surface through electrodeposition to form novel electrocatalyst. • Ni-NCN/CoFe-LDH supports strongly accelerated electron transfer, thereby improving the OER kinetics. • Ni-NCN/CoFe-LDH hybrids will hold promise in development of electrode materials. Owing to the high demand for clean and renewable energy technologies, several studies have focused on developing economically feasible, highly effective, and stable non-precious electrocatalysts for promoting the oxygen evolution reaction (OER). This development has stimulated an expansion of investigative quests and indicated the importance of advancing electrocatalytic research in this field. Through a facile and efficient method, Ni nanoparticles were uniformly embedded into nanoporous carbon nanorods (Ni-NCN), which are subsequently electrodeposited on CoFe-layered double hydroxide (LDH) nanosheets to produce highly efficient Ni-NCN/CoFe-LDH composites used for OER. The composite exhibited excellent catalytic activity toward OER owing to its low overpotential (ƞ10 mA = 280 mV), small Tafel slope (42 mV dec−1), and excellent durability. The Ni-NCN/CoFe-LDH catalyst exhibited higher OER activity owing to its uniformly dispersed Ni nanoparticles, large specific surface area, enhanced electron transport, and synergistic effect of multiple composites. Additionally, the enhanced synergistic effect of Ni-NCN promoted higher OER performance compared with Ni-undoped carbon nanorod/LDH, indicating that the Ni dopant and LDH significantly contributed to the overall OER performance. The synergistic effect of multiple composites significantly contributed to the excellent OER performance, indicating their potential as OER catalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuS nanosheets were grown uniformly on Co 9 S 8 nanotubes by low temperature oil bath. • The hollow structure of the synthesized Co 9 S 8 @CuS facilitated mass and charge transfer. • The synergistic effect of Co 9 S 8 @CuS improved its conductivity and electrochemical properties. • Co 9 S 8 @CuS/GCE showed excellent sensing performance to glucose and H 2 O 2 , respectively. Transition metal sulfides have found wide applications as promising catalysts and electrocatalysts. Herein, hollow Co 9 S 8 nanotubes were prepared through hydrothermal method, on which CuS nanosheets were grown at low temperature, and hollow Co 9 S 8 @CuS heterostructure nanocomposite was synthesized. The prepared hollow Co 9 S 8 nanotubes possess high specific surface area and efficient charge transfer ability, offering an ideal substrate for the growth of CuS nanosheets. Furthermore, the hollow structure of the synthesized Co 9 S 8 @CuS can accelerate mass transfer and provide more reaction sites with the specific area of 36.79 m2/g, and the heterostructure between Co 9 S 8 and CuS enhanced their synergistic effect on the conductivity and electrocatalytic activities. For analytical application, the synthesized Co 9 S 8 @CuS nanocomposite was applied for the determination of glucose and H 2 O 2 , with the charge transfer rate constants of 3.89 and 1.94 s−1, respectively. Under optimal conditions, the Co 9 S 8 @CuS-modified glassy carbon electrode exhibits wide linear ranges of 0.03–13 mM and 0.05–14 mM with detection limits of 5.64 μM and 6.06 μM for the oxidation of glucose and the reduction of H 2 O 2 , respectively. Additionally, real sample analyses demonstrate satisfying recoveries of 96.43 % and 101.65 % to glucose and H 2 O 2 , respectively, indicating its potential to quantitatively analyze the real samples. [ABSTRACT FROM AUTHOR]

Bismuth (Bi)-based catalysts have attracted great attention in electrocatalytic CO 2 reduction into formate, but suffer from modest activity due to insufficient active sites and slow protonation process. Here, two-dimensional (2D) defect-rich Bi 2 S 3 nanosheets are first achieved through chemical vapor sulfurization of Bi 2 O 3 solids. It is found that the defects enable the stable immobilization of S heteroatoms into 2D Bi lattice. A combination of computational and experimental analyses reveal that S dopants can not only facilitate water dissociation to construct proton-rich surface, but also concentrate potassium cations to stabilize *OCHO intermediates. Further cooperating with defects, the *OCHO formation can be both kinetically and thermodynamically boosted. Remarkably, the constructed Bi 2 S 3 nanosheets exhibit a high formate Faradaic efficiency (>90%) over a wide potential window and a high intrinsic stability over 200 h. The excellent performance in flow cell as well as promising solar-driven CO 2 electrocatalysis further demonstrate the great potential for practical implementation. [Display omitted] • 2D defective Bi 2 S 3 nanosheets were achieved through chemical vapor sulfurization. • The defects enable the stable immobilization of S heteroatoms into 2D Bi lattice. • S dopants can construct proton-rich surface by facilitating water dissociation. • The constructed Bi 2 S 3 NSs show a high formate Faradaic efficiency and stability. [ABSTRACT FROM AUTHOR]

Nanoalloy shows significant advantages and broad application prospects in chemical catalysis, due to the possessed high specific surface energy and abundant active sites can greatly promote their catalytic performance. In this work, morphology-controlled Cu-Sn alloy nanosheet arrays supported on carbon fiber paper (CP) substrate (Cu-Sn/CP) have been developed by a facile one-step electrodeposition technique at room temperature for the first time. Benefiting from the large active surface area, considerable ion transport channels and strong synergistic catalytic effect between Cu and Sn, the as-prepared Cu-Sn/CP served as a self-supported electrode for efficient nonenzymatic glucose sensing. Under optimized conditions, Cu-Sn/CP electrode offers wide linear ranges of 0.0005–2.0 mM and 2.0–10.0 mM, respectively. The detection limit is as low as 0.061 μM (S/N = 3). Cu-Sn/CP electrode also exhibited excellent selectivity and stability. Additionally, the proposed sensor is proven to be suitable for the detection of glucose in human serum samples. [Display omitted] • Morphology-controlled Cu-Sn/CP was first synthesized by a cost-efficient one step electrodeposition strategy. • Non-precious Cu-Sn alloy nanosheets were used for the electrocatalytic oxidation of glucose for the first time. • Cu-Sn/CP showed high electrocatalytic activity for glucose oxidation with wide linear range and low detection limit. • The as-proposed biosensor exhibited excellent anti-interference ability and stability. [ABSTRACT FROM AUTHOR]

Abstract: An aqueous route through MnO4 −/Mn2+ reaction under mild conditions was used to synthesize α-MnO2 nanorods. The morphological and structural evolution of α-MnO2 nanorods during their growth were tracked by Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and BET analysis. The crystallization of α-MnO2 nanorods was found to proceed through three steps: (1) Amorphous or poorly ordered nuclei formed first. (2) Then hollow nanoshperes consisting of γ-MnO2 nanorods formed via the Ostwald ripening process. (3) The hollow nanospheres broke down and the γ-MnO2 nanorods finally transformed into the α-MnO2 nanorods with increasing temperature or reaction time. The phase transformation from γ-MnO2 to α-MnO2 nanorods was accomplished by a short-range rearrangement of MnO6 octahedra. In addition, the performance of the MnO2 materials as a catalyst was evaluated in the aerobic oxidation of benzyl alcohol, showing that their catalytic activities were mainly dependent on their BET surface areas. [Copyright &y& Elsevier]

Rechargeable aqueous Zn//MnO 2 batteries are the promising alternatives to lithium-ion batteries owing to their high safety, high energy density, low cost, and environmental friendliness. However, the unstable MnO 2 cathode causes poor practical energy density and serious capacity fading. To overcome this issue, herein, a unique 2D nanosheets self-supported 3D δ -MnO 2 microflower hierarchical architecture is rationally designed and synthesized by taking advantage of its microwave-absorbing characteristics. The 2D nanosheets with high surface area could expose numerous active sites for ions/electrons transfer. Also, the 3D assembled structure acting as building blocks would ensure structural stability for long-life cycles. Benefiting from these synergistic merits, the δ -MnO 2 microflowers deliver a high capacity of 287.6 mA h g−1 at 0.5 C, an excellent rate capability of 202.7 mA h g−1 at 5 C, and a superior cycling retention of 76.5% over 1000 cycles at 10 C. Furthermore, a storage mechanism of H+/Zn2+ co-insertion accompanied by the deposition of zinc sulfate hydroxide hydrate is clarified by the aid of ex-situ XRD and SEM technologies. This work provides a new pathway for developing high capacity and long lifespan ZIBs. [Display omitted] [ABSTRACT FROM AUTHOR]

In the realm of photoelectrochemical (PEC) analysis, it is customary to employ a lone photoanode or photocathode system for analyte detection. Nonetheless, such a single detection scheme inherently carries some deficiencies. While photoanode-based PEC immunoassay methods do exhibit conspicuous photocurrent responses and heightened sensitivity, they do suffer from inadequate resistance to interference when detecting in real sample detection. Photocathode-based analysis methods are capable of effectively surmounting the limitations of photoanode-based analysis methods, but their stability is poor. Based on the above reasons, this paper reports a novel immunosensing system combining ITO/WO 3 /Bi 2 S 3 photoanode and ITO/CuInS 2 photocathode. The system that incorporates both photoanode and photocathode exhibits a steady and discernible photocurrent, possesses robust resistance to external interference, and has effectively accomplished the quantification of NSE in the linear range from 5 pg/mL to 30 ng/mL. Remarkably, the detection limit has been determined to be 1.59 pg/mL. Besides the notable advantages of satisfactory stability, exceptional specificity, and outstanding reproducibility, the sensing system also introduces an innovative approach to fabricate PEC immunosensors. [Display omitted] • A photoelectrochemical sensing platform integrating photoanode and photocathode is constructed. • The WO 3 /Bi 2 S 3 nanomaterial electrode replaces the Pt electrode as the counter electrode. • Overcome the inherent shortcomings of single-photoanode mode and single-photocathode mode. • Satisfactory detection of NSE. [ABSTRACT FROM AUTHOR]

Cyclic peptides have been widely applied in fields ranging from drug discovery to nanomaterials. After years of development, the preparation of peptide macrocycles, especially late-stage macrocyclization of peptides, remains challenging using traditional synthetic methods. This digest highlights recent developments in the synthesis of cyclic peptides. [ABSTRACT FROM AUTHOR]

[Display omitted] • KAUST-8 nanosheets are successfully synthesized with an aspect ratio of 30. • The KAUST-8/Crosslinked poly(ethylene oxide) MMMs are fabricated at a maximum loading of 35 wt.%. • The simultaneously enhanced CO 2 permeability (290% up) and CO 2 /N 2 selectivity (30% up) breaking the 2008 trade-off line. The trade-off relationship between permeability and selectivity as well as plasticization issues have largely impeded the advancement of membrane technology. Mixed-matrix-membranes (MMMs) with the incorporation of fillers into the polymer matrix is one promising method to deal with these challenges by carefully tuning their chemical properties. Compared with nanoparticles, the counterpart of nanosheet has a larger external surface area with a tendency to have closer contact with a polymer matrix to form a defect-free membrane at higher loading. This work successfully synthesized a high aspect ratio (30/1) of KAUST-8 nanosheets with high CO 2 uptake (60 cm3/g). This enables an optimal loading of 30 wt.% in the CO 2 -attractive crosslinked poly(ethylene oxide) (XLPEO) membrane and results in the simultaneously enhanced CO 2 permeability and CO 2 /N 2 selectivity with 280 % and 30 % up, respectively in the mixed gas permeation measurements (50/50 vol.). The resultant membrane performance surpassed the 2008 Robeson upper bound. Meanwhile, the stabilized MMM performance of up to 6 bar and high thermal stability of up to 350 °C bring extra benefits to the KAUST-8-based XLPEO membrane for post-combustion flue gas treatment. [ABSTRACT FROM AUTHOR]

Generally, the photoanodic photoelectrochemical (PEC) immunoassay method has an outstanding photocurrent and low detection limit, but its poor anti-interference ability in the detection of real samples restricts its performance. The photocathode immunoassay method has an excellent ability to see interference in actual sample detection, but it has its own defect in that the photocurrent is not obvious. Here, a promising new cathodic PEC immunosensing platform is reported, which integrates a photocathode and photoanode. The photoanode and photocathode are WO 3 /Mn:CdS composite modified and reduced graphene oxide (RGO) modified indium tin oxide (ITO) electrodes, respectively. In addition to an excellent PEC response, the immunosensor constructed by the integrating the photoanode and photocathode also has good anti-interference ability in actual sample analysis. The constructed immunosensor achieves accurate detection of NSE with a range from 5.0 pg/mL to 20 ng/mL, and the limit of detection (LOD) is 1.2 pg/mL. The proposed immunoassay method has good stability, selectivity and reproducibility. Moreover, it introduces new ideas for the construction of PEC immunosensors. [ABSTRACT FROM AUTHOR]

Semiconducting photocatalysts composited with noble nanometals can be regarded as one of effective strategies to enhance the photocatalytic activity, attributed to a synergy of heterojuction formation and surface plasmon resonance effect. However, the dosage of nanometal in the composite for achieving an optimal performance is commonly larger than 10 wt%, causing high cost in raw materials. In this work, a composite photocatalyst of flower-like bismuth tungstate (Bi 2 WO 6) nanosheets decorated by low-dosage silver nanoparticles (Ag NPs) with the excellent photocatalytic activity for sulfamethoxazole (SMX) degradation was prepared. Further, the morphological and structural characteristics, chemical compositions, and photoelectrical properties of this composite photocatalyst (Ag/Bi 2 WO 6) were investigated. Different loading amounts of Ag NPs (1, 3 and 5 wt%) in Ag/Bi 2 WO 6 were modulated, and when the dosage of Ag NPs was controlled to be only 3 wt%, the composite photocatalyst exhibited the most efficient degradation that 95.04% of SMX was removed within 60 min under visible light irradiation, which has around 3 times enhancement compared to single Bi 2 WO 6. The sacrificial agent experiment indicated that •O2− and •OH are the main active substances in the photocatalytic degradation of SMX. And the cyclic experiment further confirmed the Ag/Bi 2 WO 6 composite with high stability and reusability. The photocatalytic mechanism was verifiably proposed that the enhanced degradation performance was derived from more effective light absorption and photogenerated charge separation by loading Ag NPs onto Bi 2 WO 6. Our primary results provide a basic platform for exploring the high catalytic-activity photocatalysts with low-dosage noble nanometals. [ABSTRACT FROM AUTHOR]