Double-shelled Hollow Structure Research Articles

Coupling effects of dielectric loss in N-doped carbon double-shelled hollow particles for high-performance microwave absorption

Microwave absorbing materials with lightweight and high-performance are of great significance for electronic technique, ecological environment and defense applications. The hollow structure of carbon microspheres is beneficial to achievement of high-performance microwave absorption due to high interfacial polarization. However, the key characteristic is still unclear to control interfacial polarization. Herein, double-shelled N-doped carbon hollow particles derived from polypyrrole by self-sacrifice template were synthesized. The polymerization process was controlled by the interface between solid and pyrrole acid liquid in Fe3O4 disperse system, subsequently, micro-nano structure of carbon was tuned. The N-doped carbon double-shelled hollow particles (DSHS) show a strong dielectric loss due to coupling effect of resistance loss and interfacial polarization owing to the double-shelled hollow structure. Thus, DSHS shows a high-performance microwave absorption with minimum reflection loss (RLmin) of −75.10 dB at a thickness of 2.48 mm and effective absorption bandwidth (RL ≤ -10 dB) of 6.08 GHz and 4.05 GHz covering the whole Ku band and almost the whole X with a thickness of 2.21 mm and 3.00 mm, respectively. This work provides a simple approach for synthesizing N-doped carbon particles with distinct micro-nano hierarchical structure, double-shelled hollow microspheres assembled by nanoparticles have potential application as a high-performance MAM.

Design of double-shelled NiS-FeS@NC hollow nanocubes for high-performance sodium-ion batteries

Mixed metal sulfides (MMSs) are highly noticeable as prospective materials for sodium storage due to their prominent electrochemical reversibility and excellent redox activity. Nevertheless, the fast capacity decay and poor rate capability hinder their application in sodium-ion batteries (SIBs). In this work, a facile template method, using Prussian blue analogue as the precursor, was employed to fabricate the double-shelled hollow structure with nitrogen (N)-doped carbon layer coated on the outer shell of NiS-FeS hollow nanocubes (NiS-FeS@NC). Specifically, the NiS-FeS@NC composite provides a glorious reversible capacity (395.8 mAh g−1 after 200 cycles at 1.0 A g−1) and superior rate capability (322.2 mAh g−1 at 5.0 A g−1) when employed as electrode material for SIBs. In addition, the designed NiS-FeS@NC= |Na3V2(PO4)2 @C full battery can maintain an excellent reversible capacity (68.7 mAh g−1 after 200 cycles at 1.0 A g−1) as well as robust cycling stability. The improvement of the sodium storage performance can be mainly attributed to the synergistic coupling of the N-doped carbon coating layer and the hollow nanostructure, which can effectively maintain the integrity of the nanocube structure and accelerate the transportation of electrons/ions, thus contributing to improving the electrochemical sodium storage performance. Importantly, the unique modification strategy reported in this paper, combining with the mechanism and kinetics revealing, is expected to provide insights for facilitating high-performance electrodes for SIBs.

Template-free formation of BiOCl double-shelled hollow microspheres with enhanced carbamazepine removal efficiency

Constructing three-dimensional (3D) hierarchical structure is regarded as an effective strategy to alleviate the inherent drawbacks of the BiOCl bulk structure and realize the optimization of photocatalytic performance. Herein, a unique BiOCl double-shelled hollow microsphere structure with adjustable shell thickness is fabricated through a template-free one-pot solvothermal method for the first time. A plausible formation mechanism is proposed by exploring the morphological changes during the growth process. The as-obtained hollow microspheres photocatalyst exhibits excellent carbamazepine (CBZ) degradation efficiency (97.5%) under simulated solar irradiation, the corresponding apparent rate constant is about 4 times and 3 times than that of conventional BiOCl solid microspheres. The experimental and characterization results show that the existence of nanosheet subunits and porous structures shorten the diffusion length of charge carriers, which is conducive to the separation and transfer of photogenerated. Meanwhile, the construction of double-shelled hollow structure achieves higher light utilization. This work demonstrates the superior performance of catalysts with hierarchical hollow structures for pollutant degradation and provides new ideas to further optimize the photocatalytic performance of BiOCl-based materials.

Highly efficient synthesis of CeO2@g-C3N4 double-shelled hollow spheres for ultrasensitive self-enhanced electrochemiluminescence biosensors

In this work, CeO2@g-C3N4 double-shelled hollow spheres were skillfully synthesized as a novel type self-enhanced electrochemiluminescent (ECL) emitter by a highly efficient outside-in hard template method. Thanks to its great catalytic ability, CeO2 were served as a co-reaction accelerator for improving ECL performance of the hollow g-C3N4 spheres (HCNSs)/S2O82− system. In addition, the self-enhanced ECL emitter is designed as a complex containing a co-reaction accelerator and a luminophore to shorten the electron transfer path, which decreases the energy loss of the luminophore significantly. More importantly, the unique double-shelled hollow structure not only greatly decreases the inner filtering effect, but also maximizes the utilization efficiency of the ECL luminophores by increasing a CeO2 shell inside the HCNSs as co-reaction accelerator, effectively enhancing the ECL intensity. Under the optimal conditions, the designed ECL immunosensor showed excellent performance in the determination of CA19-9 with a linear range of 0.50 mU mL−1 –500.00 U mL−1 and a low detection limit of 0.039 mU mL−1. Importantly, the resulting biosensor has good stability, high sensitivity and reliable reproducibility, suggesting its potential application in clinical research.

Engineering tandem double p-n heterostructured CeO2@CdS-Cu8S5 hollow spheres for remarkable photocatalytic CO2 reduction

Carbon cycling and value-added CO2 utilization through photocatalytic CO2 reduction are effective strategies for solving environmental problems and energy crises. Here, we rationally design and fabricate a double p-n heterostructured CeO2@CdS-Cu8S5 double-shelled hollow sphere (DSHSs) photocatalyst, which efficiently and stably performs photocatalytic CO2 reduction under visible light irradiation. Firstly, CeO2 hollow spheres were prepared by the template-assisted method. Then ultrathin CdS nanolayers were grown in situ by the chemical bath deposition method. Finally, part of the CdS was converted to Cu8S5 by cation exchange, resulting in the CeO2@CdS-Cu8S5 hybrid with uniform interfacial contact and ultrathin double-shelled hollow spherical structure. The constructed tandem double p-n heterostructure contributes to the excellent photo-induced charge separation and migration capability of the CeO2@CdS-Cu8S5 photocatalyst. Thanks to the multiple light scattering inside the double-shelled hollow structure, solar radiation can be absorbed more efficiently. In addition, the abundant exposed active sites also significantly contribute to the chemisorption of CO2 molecules and the progress of surface redox reactions. Based on the above properties, the optimized CeO2@CdS-Cu8S5 DSHSs without any noble metal cocatalyst exhibited excellent activity (18.25 µmol g–1h−1) and high selectivity (89.3%) during the photocatalytic reduction of CO2 deoxygenation to CH4.

Cefazolin-Loaded Double-Shelled Hollow Mesoporous Silica Nanoparticles/Polycaprolactone Nanofiber Composites: A Delivery Vehicle for Regenerative Purposes.

Purpose: As important challenges in burn injuries, infections often lead to delayed and incomplete healing. Wound infections with antimicrobial-resistant bacteria are other challenges in the management of wounds. Hence, it can be critical to synthesize scaffolds that are highly potential for loading and delivering antibiotics over long periods. Methods: Double-shelled hollow mesoporous silica nanoparticles (DSH-MSNs) were synthesized and loaded with cefazolin. Cefazolin-loaded DSH-MSNs (Cef*DSH-MSNs) were incorporated into polycaprolactone (PCL) to prepare a nanofiber-mediated drug release system. Their biological properties were assessed through antibacterial activity, cell viability, and qRT-PCR. The morphology and physicochemical properties of the nanoparticles and nanofibers were also characterized. Results: The double-shelled hollow structure of DSH-MSNs demonstrated a high loading capacity of cefazolin (51%). According to in vitro findings, the Cef*DSH-MSNs embedded in polycaprolactone nanofibers (Cef*DSH-MSNs/PCL) provided a slow release for cefazolin. The release of cefazolin from Cef*DSH-MSNs/PCL nanofibers inhibited the growth of Staphylococcus aureus. The high viability rate of human adipose-derived stem cells (hADSCs) in contact with PCL and DSH-MSNs/PCL was indicative of the biocompatibility of nanofibers. Moreover, gene expression results confirmed changes in keratinocyte-related differentiation genes in hADSCs cultured on the DSH-MSNs/PCL nanofibers with the up-regulation of involucrin. Conclusion: The high drug-loading capacity of DSH-MSNs presents these nanoparticles as suitable vehicles for drug delivery. In addition, the use of Cef*DSH-MSNs/PCL can be an effective strategy for regenerative purposes.

Double‐shell and yolk‐shell structured ZnSe ‐carbon nanospheres as anode materials for high‐performance potassium‐ion batteries

Transition-metal chalcogenides are prospective anode materials for potassium-ion batteries. Herein, crystalline ZnSe nanocrystal-loaded hollow carbon nanospheres (ZnSe-HC) are synthesized by infiltration of zinc nitrate and selenium dioxide into hollow carbon nanospheres and subsequent selenization. The electrochemical reaction mechanism of ZnSe with K-ion is systematically examined by ex-situ X-ray photoelectron spectroscopy and transmission electron microscopy. Two samples with distinctive nanostructures, which are double-shelled hollow structure and yolk-shelled structure, can be fabricated by controlling the selenization temperature, and their K-ion storage performances are compared. The double-shelled ZnSe-HC, which is prepared at a lower temperature, exhibits superior cycling and rate performances to those of the yolk-shelled ZnSe-HC. For double-shelled ZnSe-HC, small ZnSe nanocrystals embedded in the carbon shell and dispersed over the inner carbon shell contribute to the structural stability and fast kinetics during repeated cycles. As a result, the double-shelled ZnSe-HC exhibits a stable cycling performance (400 mA h g−1 at 0.1 A g−1 after 100 cycles) and excellent rate capability (240 mA h g−1 at 3.0 A g−1).

Double-shelled Mn-doped NiCo2S4 hollow nanowire arrays for high-reactivity hybrid supercapacitors

Double-shelled Mn-doped NiCo2S4 (NiCoMn–S-h) hollow nanowire arrays are synthesized for optimized reactivity of hybrid supercapacitors. The NiCoMn–S-h is converted based on anion exchange reaction, which maintains the overall array structure of precursor and forms a double-shelled hollow structure. It is found that Mn composition lowers outer diffusion rate of precursor for the formation of inner shell of double-shelled structure. The specific structure and Mn-doping promote the performance of sulfides. As a result, the NiCoMn–S-h shows high specific capacity, improved rate performance and low charge transfer resistance as the battery electrode for hybrid supercapacitors. The NiCoMn–S-h exhibits a specific capacity of 948 C g−1 at 1 A g−1 combined with a highly retained specific capacity of 614 C g−1 at 50 A g−1. The NiCoMn–S-h displays well matched performance with the capacitive electrode in hybrid supercapacitors, which exhibits both high-energy and high-power performances with specific energy of 44.9 Wh kg−1 at 780 W kg−1 and 19.2 Wh kg−1 at 23.4 kW kg−1 delivered.

Mo2 C/C Hierarchical Double-Shelled Hollow Spheres as Sulfur Host for Advanced Li-S Batteries.

One of the major challenges regarding the sulfur cathode of Li-S batteries is to achieve high sulfur loading, fast Li ions transfer, and the suppression of lithium polysulfides (LiPSs) shuttling. This issue can be solved by the development of molybdenum carbide decorated N-doped carbon hierarchical double-shelled hollow spheres (Mo2 C/C HDS-HSs). The mesoporous thick inner shell and the central void of the HDS-HSs achieve high sulfur loading, facilitate the ion/electrolyte penetration, and accelerate charge transfer. The microporous thin outer shell suppresses LiPSs shuttling and reduces the charge/mass diffusion distance. The double-shelled hollow structure accommodates the volume expansion during lithiation. Furthermore, Mo2 C/C composition renders the HDS-HSs cathode with improved conductivity, enhanced affinity to LiPSs, and accelerated kinetics of LiPSs conversion. The structural and compositional advantages render the Mo2 C/C/S HDS-HSs electrode with high specific capacity, excellent rate capability, and ultra-long cycling stability in the composed Li-S batteries.

Double-Shelled Hollow SiO2 @N-C Nanofiber Boosts the Lithium Storage Performance of [PMo12 O40 ]3.

Polyoxometalates (POMs)-based materials, with high theoretical capacities and abundant reversible multi-electron redox properties, are considered as promising candidates in lithium-ion storage. However, the poor electronic conductivity, low specific surface area and high solubility in the electrolyte limited their practical applications. Herein, a double-shelled hollow PMo12 -SiO2 @N-C nanofiber (PMo12 -SiO2 @N-C, where PMo12 is [PMo12 O40 ]3- , N-C is nitrogen-doped carbon) was fabricated for the first time by combining coaxial electrospinning technique, thermal treatment and electrostatic adsorption. As an anode material for LIBs, the PMo12 -SiO2 @N-C delivered an excellent specific capacity of 1641 mA h g-1 after 1000 cycles under 2 A g-1 . The excellent electrochemical performance benefited from the unique double-shelled hollow structure of the material, in which the outermost N-C shell cannot only hinder the agglomeration of PMo12 , but also improve its electronic conductivity. The SiO2 inner shell can efficiently avoid the loss of active components. The hollow structure can buffer the volume expansion and accelerate Li+ diffusion during lithiation/delithiation process. Moreover, PMo12 can greatly reduce charge-resistance and facilitate electron transfer of the entire composites, as evidenced by the EIS kinetics study and lithium-ion diffusion analysis. This work paves the way for the fabrication of novel POM-based LIBs anode materials with excellent lithium storage performance.

Nanocatalyst-mediated oxygen depletion in epoxy coating for active corrosion protection

Smart coatings depending on external nanocontainers are often complex and expensive, which can only inhibit local corrosion depending on the microenvironment change after corrosion. In this work, nanocatalytic anticorrosion based on silica coated nitrogen enriched hollow carbon spheres (NHCs@mSiO2) is developed to achieve the prolongation of coating lifetime and long-term protection of metals. Obtained NHCs@mSiO2 by confined space pyrolysis strategy shows a double-shelled hollow structure with interior N-doped carbon shell and exterior silica shell. Moreover, the NHCs@mSiO2 spheres possess favorable catalytic ability for oxygen thanks to the incorporation of nitrogen. When blended into epoxy coatings, amphiphilic NHCs@mSiO2 spheres distribute uniformly and occupy the pores or cracks in composite coatings. The diffused oxygen through coating micropores are preferentially adsorbed by NHCs@mSiO2 and directly reduced to water through four-electron pathways. Therefore, the corrosion is greatly avoided due to the depletion of oxygen. The introduction of nano-catalyst with excellent dispersity and oxygen reduction ability will pave the way toward the development of new smart coatings with active corrosion resistance.

Preparation of Co3O4/NiCo2O4@NC double-shelled catalyst and its high performance for degradation of levodopa in Electro-Fenton system

Based on the pyrolysis of zeolitic imidazolate framework-67/Ni-Co layered double hydroxide (ZIF-67/Ni-Co LDH) precursor, we successfully prepare a novel Co3O4/NiCo2O4@NC double-shelled hollow structure catalyst. After carbonization, Co3O4/NiCo2O4@NC inherit the polyhedral shape from ZIF-67/Ni-Co LDH. At the same time, obvious inter-shell pores appear between the inner shell and outer shell of Co3O4/NiCo2O4@NC. Compared with simple single-shell Co3O4@NC catalyst, more complex hollow structure brings better electrochemical performance of the material. Co3O4/NiCo2O4@NC modified graphite felt (GF) electrode is used to degrade levodopa in Electro-Fenton (EF) system. According to the experimental results, the removal rate of levodopa and TOC have reached 99.07% and 60.16%, respectively after 2 h reaction. The EF reaction for the degradation of levodopa follows a pseudo first-order kinetic model. Based on the intermediate product, we propose a possible degradation pathway of levodopa. In addition, we have evaluated the reusability of Co3O4/NiCo2O4@NC-GF electrode in EF reaction. Finally, we believe that the Co3O4/NiCo2O4@NC-GF electrode is a promising cathode for the treatment of pharmaceutical wastewater in EF field.

Rational Construction of Ruthenium‐Cobalt Oxides Heterostructure in ZIFs‐Derived Double‐Shelled Hollow Polyhedrons for Efficient Hydrogen Evolution Reaction

Transition metal oxides (TMOs) and their heterostructure hybrids have emerged as promising candidates for hydrogen evolution reaction (HER) electrocatalysts based on the recent technological breakthroughs and significant advances. Herein, Ru-Co oxides/Co3 O4 double-shelled hollow polyhedrons (RCO/Co3 O4 -350 DSHPs) with Ru-Co oxides as an outer shell and Co3 O4 as an inner shell by pyrolysis of core-shelled structured RuCo(OH)x @zeolitic-imidazolate-framework-67 derivate at 350 °C are constructed. The unique double-shelled hollow structure provides the large active surface area with rich exposure spaces for the penetration/diffusion of active species and the heterogeneous interface in Ru-Co oxides benefits the electron transfer, simultaneously accelerating the surface electrochemical reactions during HER process. The theory computation further indicates that the existence of heterointerface in RCO/Co3 O4 -350 DSHPs optimize the electronic configuration and further weaken the energy barrier in the HER process, promoting the catalytic activity. As a result, the obtained RCO/Co3 O4 -350 DSHPs exhibit outstanding HER performance with a low overpotential of 21mV at 10mA cm-2 , small Tafel slope of 67mV dec-1 , and robust stability in 1.0 m KOH. This strategy opens new avenues for designing TMOs with the special structure in electrochemical applications.

Bimetal carbonaceous templates for multi-shelled NiCo2O4 hollow sphere with enhanced xylene detection

Abstract Xylene (C8H10) is one of the most hazardous volatile organic compounds, thus highly sensitive gas sensor with real-time monitoring capabilities at lower concentration level is crucial. Hollow and multi-shelled oxide nanostructures are very promising design options for gas sensors due to their low density, high surface area and well-aligned nano-porous structures with less agglomerated configurations. Here, NiCo2O4 double-shelled hollow spheres (DHSs) with porous surfaces are successfully synthesized via a self-templating strategy followed by a simple post-annealing process, in which bimetal self-assembly carbonaceous microspheres (CMS) are employed as a sacrificial template. The crystallinity, morphology, and microstructure of NiCo2O4 DHSs are detailedly characterized. The formation mechanism of double-shelled hollow structure is also discussed. The as-prepared NiCo2O4 DHSs possess large specific surface area as high as ∼93.5 m2 g−1, which not only supply outstanding gas permeability and more reactive sites but also accelerate the diffusion of gas molecules. The sensitivity and response time based on NiCo2O4 DHSs are 23.3 and 15.4 s to 100 ppm xylene at the optimal working temperature (240 °C), respectively.

SnO2/ZnSnO3 double-shelled hollow microspheres based high-performance acetone gas sensor

In this study, the preparation process and the sensing performance toward acetone of SnO2/ZnSnO3 composite microspheres with the double-shelled hollow structure were reported. It was synthesized by one-step chemical vapor deposition (CVD) method using sucrose as solid precursor pyrolysis carbon template. In addition, the internal structure of the composite microspheres can be effectively controlled by changing the sucrose concentration. The perfect double-shelled hollow structure (average diameter of about 500 nm) of the prepared sensitive materials was observed through SEM and TEM. It is noteworthy that the double-shelled hollow structure had a large specific surface area (188.60 m2/g), which can both increase the internal and external reactive sites of the sensitive material effectively. Compared with other obtained composite microspheres, the SnO2/ZnSnO3 sample with double-shelled hollow structure presented the best sensing performance, and the response to 100 ppm acetone reached 30 at 290 °C. Furthermore, it also presented excellent selectivity and long-term stability to acetone. The excellent performance was attributed to the synergistic effect of the double-shelled hollow structure with large specific surface area and the n-n heterojunction at the interface of the SnO2/ZnSnO3 composite. The sensing mechanisms of the double-shelled hollow SnO2/ZnSnO3 composite material were discussed in detail.

Activating peroxydisulfate with Co3O4/NiCo2O4 double-shelled nanocages to selectively degrade bisphenol A – A nonradical oxidation process

In this study, zeolitic imidazolate framework-67 (ZIF-67) derived Co3O4/NiCo2O4 double-shelled nanocages (DSNCs) were fabricated and utilized as catalysts to activate peroxydisulfate (PDS) for bisphenol A (BPA) degradation. The results showed that Co3O4/NiCo2O4 DSNCs exhibited superior BPA degradation performance over Co3O4 NCs and NiCo2O4 NCs. PDS combined with the interfaces of both the Co3O4 inner shell and NiCo2O4 outer shell to form complex, inducing the nonradical oxidation of BPA by electron abstraction. The double-shelled hollow structure helped to increase the instantaneous concentration of reactants in the void space of Co3O4/NiCo2O4 DSNCs, thus promoting the decomposition of BPA. The Co3O4/NiCo2O4 DSNCs had high selectivity for BPA degradation and were resistant to halogens and background organic matter in wastewater. Our work indicated that metal-organic framework (MOF)-derived nanomaterials with a hollow structure have a promising application prospect for persulfate-based advanced oxidation technology.

Enhanced ammonia detection using wrinkled porous CoFe2O4 double-shelled spheres prepared by a thermally driven contraction process

Hierarchical CoFe2O4 double-shelled hollow spheres (DHSs) with wrinkled porous surfaces are successfully synthesized via a self-templating strategy followed by a simple post-annealing process. The crystallinity, morphology, and microstructure of CoFe2O4 DHSs are detailedly characterized. The as-prepared CoFe2O4 DHSs are composed of homogeneous primary nanoparticles with uniform size and morphology that are hierarchically assembled into well-defined double-shelled spheres with high porosity. The formation mechanism of double-shelled hollow structure is also discussed. Because of their large specific surface area and easily penetrable hierarchical shells, the as-synthesized CoFe2O4 DHSs exhibit high sensitivity to ammonia and fast response-recovery capability at the optimal working temperature.

Preparation and NH3 Gas-Sensing Properties of Double-Shelled Hollow ZnTiO3 Microrods.

A novel double-shelled hollow (DSH) structure of ZnTiO3 microrods was prepared by self-templating route with the assistance of poly(diallyldimethylammonium chloride) (PDDA) in an ethylene glycol (EG) solution, which was followed by calcining. Moreover, the NH3 gas-sensing properties of the DSH ZnTiO3 microrods were studied at room temperature. The morphology and composition of DSH ZnTiO3 microrods films were analyzed using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The formation process of double-shelled hollow microrods was discussed in detail. The comparative gas-sensing results revealed that the DSH ZnTiO3 microrods had a higher response to NH3 gas at room temperature than those of the TiO2 solid microrods and DSH ZnTiO3 microrods did in the dark. More importantly, the DSH ZnTiO3 microrods exhibited a strong response to low concentrations of NH3 gas at room temperature.

Facile fabrication of double-shelled hollow SnO2@C nanoparticles with improved lithium storage via a novel heterogeneous template strategy

Tin dioxide (SnO2) has been considered as one of the most promising candidates to surpass the capacity limitation of conventional graphite anode of lithium-ion batteries. However, the tremendous volume change of SnO2 generated during cycling process gives rise to poor cycling performance and thus seriously impedes the practical use of SnO2 anode in lithium-ion batteries. It is suggested that fabrication of double-shelled hollow nanostructured SnO2/C composites is expected to be able to solve above problem effectively, but is difficult to be achieved because of the increased complexity of the structures. Herein, we for the first time demonstrate a novel heterogeneous template strategy to facilely fabricate double-shelled hollow SnO2@C nanoparticles (DSH SnO2@C). It is worthy of noting that the double-shelled hollow structure is formed in one-step hydrothermal process, due to the rational adoption of a heterogeneous template and therefore shows facile characteristic. The shells of DSH SnO2@C consist of ultra-fine SnO2 nanocrystals as well as the outer ultra-fine SnO2 nanocrystals are further coated by a thin layer of amorphous carbon, hence have many structural characteristics such as large specific surface area, rich pores, adequate free space, and carbon coating. As expected, the as-prepared DSH SnO2@C presents improved lithium storage performance as an anode for lithium-ion batteries, exhibiting a high capacity of 769 mAh g−1 at 200 mA g−1 after even 350 cycles, which is around 98.6% retention of the second cycle. Moreover, thus concept of heterogeneous template strategy may be extended to design and fabrication of other metal oxides-based nanocomposites with double-shelled hollow structures for application in other various fields such as catalysis, drug delivery and sensor.

A novel nonenzymatic electrochemical sensor based on double-shelled CuCo2O4 hollow microspheres for glucose and H2O2

CuxCo3-xO4 (x = 0.5, 1, 1.5, 2) are successfully synthesized through hydrothermal and calcination processes. A series of electrochemical tests reveal that all of them exhibit electrocatalytic activity towards glucose and H2O2. Among them, CuCo2O4 (x = 1) has a unique double-shelled hollow structure and shows higher catalytic performance. The electrochemical sensor based on CuCo2O4 displays a linear range from 2.5 μM to 7.9 mM, with a sensitivity of 400.0 μA mM−1cm−2 for the detection of glucose. As for H2O2, it shows a linear range from 10.0 μM to 8.9 mM, with a sensitivity of 94.1 μA mM−1cm−2. The sensor also exhibits short response time (<3 s), good selectivity, reproducibility, and stability over 18 days. Thus, this novel non-enzyme sensor has potential application in glucose and H2O2 detection.