Prussian Blue Microcubes Research Articles

Quantification of Neuronal Cell-Released Hydrogen Peroxide Using 3D Mesoporous Copper-Enriched Prussian Blue Microcubes Nanozymes: A Colorimetric Approach in Real Time and Anticancer Effect.

Despite the effectiveness and selectivity of natural enzymes, their instability has paved the way for developing nanozymes with high peroxidase activity using a straightforward technique, thereby expanding their potential for multifunctional applications. Herein, meso-copper-Prussian blue microcubes (Meso-Cu-PBMCs) nanozymes were successfully prepared via a cost-effective hydrothermal route. It was found that the Cu-PBMCs nanozymes, with three-dimensional (3D) mesoporous cubic morphologies, exhibited an excellent peroxidase-like property. Based on the high affinity of Meso-Cu-PBMCs toward H2O2 (Km = 0.226 μM) and TMB (Km = 0.407 mM), a colorimetric sensor for in situ H2O2 detection was constructed. On account of the high catalytic activity, affinity, and cascade strategy, the Meso-Cu-PBMCs nanozyme generated rapid multicolor displays at varying H2O2 concentrations. Under optimized conditions, the proposed sensor exhibits a preferable sensitivity of 18.14 μA μM-1, a linear range of 10 nM-25 mM, and a detection limit of 6.36 nM (S/N = 10). The reliability of the sensor was verified by detecting H2O2 in spiked human blood serum and milk samples, as well as by detecting in situ H2O2 generated from the neuron cell SH-SY5Y. Besides, the Meso-Cu-PBMCs nanozyme facilitated the catalysis of H2O2 in cancer cells, generating •OH radicals that induce the death of cancer cells (HCT-116 colon cancer cells), which holds substantial potential for application in chemodynamic therapy (CDT). This proposed strategy holds promise for simple, rapid, inexpensive, and effective intracellular biosensing and offers a novel approach to improve CDT efficacy.

3D Honeycomb Fe/MXene Derived from Prussian Blue Microcubes with a Tunable Structure for Efficient Low-Frequency and Flexible Electromagnetic Absorbers.

The unique layered structure and high conductivity of MXene materials make them highly promising for microwave absorption. However, the finite loss mechanism and severe agglomeration present challenging obstacles for ideal microwave absorbers, which could be effectively improved by constructing a three-dimensional (3D) porous structure. This study reports a 3D honeycomb MXene using a straightforward template method. The 3D MXene framework offers ample cavities to anchor the Prussian blue microcubes and their derivatives including Fe microboxes and Fe clusters by a simple annealing process. Based on the superiority of the 3D honeycomb architecture and magnetic-dielectric synergistic effects, the Fe/MXene absorbers demonstrate outstanding microwave absorption capabilities with the optimum reflection loss value of -40.3 dB at 2.00 mm in the low-frequency range from 4.2 to 5.6 GHz. The absorber also manifests superior radar wave attenuation by finite element analysis and exhibits great potential to be a flexible and thermal insulation material in a wide range of temperatures. This work proposes a useful reference for the design of 3D MXene-based porous architectures, and the synergistic magnetic-dielectric strategy further expands the potential of MXene-based absorbers, enabling them to be used as flexible and highly efficient microwave absorbers.

Prussian blue microcubes-derived FeF3 cathodes for high-energy and ultra-stable lithium and lithium-ion batteries

Iron trifluoride (FeF3) is highlighted as a competitive cathode for next-generation lithium and lithium-ion batteries with higher energy densities and lower cost. However, the FeF3 cathode is typically hindered by rapid capacity fade for their poor electronic/ionic conductivity and unstable electrode/electrolyte interphase. Herein, a microcubic FeF3@C composite, where the nanosized FeF3 particles (<40 nm) are encapsulated by graphitized carbon and linked through surrounding amorphous carbon matrix, is firstly synthesized through the Prussian blue microcubes. When using as the cathode of coin-type lithium batteries, it can achieve stable and ultralong lifespan (over 1000 cycles) at FeF3 mass loading of ∼2 mg cm−2, ascribing to the compact and thick wrapping of carbon shell and stable cathode solid electrolyte interphase (CEI) during cycling. Besides, the FeF3–Li pouch cell, FeF3 full batteries with pre-lithiated Li4Ti5O12 (PLLTO) and pre-lithiated mesocarbon microbeads (PLMCMB) anodes are successfully constructed. To interpret the capacity rising of as-prepared FeF3 cathodes within initial cycles, the detailed electrochemical behaviors and electrode kinetics are investigated. The results show that the decay of the high-potential decomposition process cannot catch up with the activation of the low-potential conversion reaction The repeated electrochemical activation within initial cycles causes multiple interface and increased Li+ diffusion coefficient (resulted from the amorphization of FeF3 particle), which induce the capacity rising.

Preparation and fabrication of porous-Fe2O3/carbon black nanocomposite: a portable electrochemical sensor for psychotropic drug detection in environmental samples

Herein, we reported the fabrication of porous iron oxide/carbon black (P–Fe2O3/CB) composite through a two-step engineering method. At first, Prussian blue microcubes were used as a precursor and further calcined to form P–Fe2O3 microcubes. The intercalation of CB nanoparticles with P–Fe2O3 nanocubes was processed through the ultrasonication method. The obtained P–Fe2O3/CB were successfully scrutinized through various physiochemical characterization methods. The proposed P–Fe2O3/CB-modified glassy carbon electrode sensor was successfully implemented in the electrochemical sensing of chlorpromazine hydrochloride due to its very low charge transfer resistance (Rct) compared to the other electrode modifiers. The sensitive detection of CPMH through differential pulse voltammetry exemplifies an excellent electroanalytical performance such as a wide linear range of 0.5–1472 μM, a lower detection limit (0.001 μM), and an appraisable sensitivity of 1.99 μA/μM cm−2 due to its availability of a high number of active sites and its large surface area, respectively. It also expresses excellent selectivity, repeatability, reproducibility, and stability results. Moreover, the practical feasibility of the as-fabricated P–Fe2O3/CB/glassy carbon electrode sensor shows exquisite recovery (98.1–100.8%) results with an appraisable current response in various biological, pharmaceutical, and environmental samples.

Microstructured ZrO2 coating of iron oxide for enhanced CO2 conversion

This work provides a way to design oxygen carriers for chemical looping. Starting from Prussian blue microcubes, Zr-promoted Fe-based materials are developed for the conversion of CO2 into CO. Thermally induced oxidative decomposition of ZrO2-coated Prussian blue under the protection of the firstly formed ZrO2 shell leads to the formation of hollow structured materials.Detailed activity tests and in-situ characterization are used to investigate the relationship between material structure, stability and CO yield from CO2 conversion. Throughout one hundred H2-CO2 redox cycles, 10 %Fe2O3/ZrO2 exhibits a 27 times higher CO space-time yield (86mmol∙s-1∙kgFe2O3-1) than unpromoted, yet hollow structured Fe2O3. This superior performance derives from the dual role that ZrO2 plays: protecting the structure, thereby improving the iron oxide sintering resistance, and facilitating the reduction of iron oxide during redox cycles. The hollow structure and the interaction between Fe2O3 and ZrO2 are the main reasons for the enhanced redox activity.

Reversible structural evolution of sodium-rich rhombohedral Prussian blue for sodium-ion batteries

Iron-based Prussian blue analogs are promising low-cost and easily prepared cathode materials for sodium-ion batteries. Their materials quality and electrochemical performance are heavily reliant on the precipitation process. Here we report a controllable precipitation method to synthesize high-performance Prussian blue for sodium-ion storage. Characterization of the nucleation and evolution processes of the highly crystalline Prussian blue microcubes reveals a rhombohedral structure that exhibits high initial Coulombic efficiency, excellent rate performance, and cycling properties. The phase transitions in the as-obtained material are investigated by synchrotron in situ powder X-ray diffraction, which shows highly reversible structural transformations between rhombohedral, cubic, and tetragonal structures upon sodium-ion (de)intercalations. Moreover, the Prussian blue material from a large-scale synthesis process shows stable cycling performance in a pouch full cell over 1000 times. We believe that this work could pave the way for the real application of Prussian blue materials in sodium-ion batteries.

Flexible Na/K‐Ion Full Batteries from the Renewable Cotton Cloth–Derived Stable, Low‐Cost, and Binder‐Free Anode and Cathode

Flexible Na/K‐ion batteries (NIBs/KIBs) exhibit great potential applications and have drawn much attention due to the continuous development of flexible electronics. However, there are still many huge challenges, mainly the design and construction of flexible electrodes (cathode and anode) with outstanding electrochemical properties. In this work, a unique approach to prepare flexible electrode is proposed by utilizing the commercially available cotton cloth–derived carbon cloth (CC) as a flexible anode and the substrate of a cathode. The binder‐free, self‐supporting, and flexible cathodes (FCC@N/KPB) are prepared by growing Prussian blue microcubes on the flexible CC (FCC). Na/K‐ion full batteries (FCC//FCC@N/KPB) are assembled by using FCC and FCC@N/KPB as anode and cathode, respectively. Electrochemical performance, mechanical flexibility, and practicability of FCC//FCC@N/KPB Na/K‐ion full batteries are evaluated in both coin cells and flexible pouch cells, demonstrating their superior energy‐storage properties (excellent rate performance and cycling stability) and remarkable flexibility (they can work under different bending states). This work provides a new and profound strategy to design flexible electrodes, promoting the development of flexible NIBs/KIBs to be practical and sustainable.

Iron nanoparticles in capsules: derived from mesoporous silica-protected Prussian blue microcubes for efficient selenium removal.

A spatially confined reduction strategy for the fabrication of small nanoparticles in a micro-box is reported, where iron nanoparticles with uniform diameter are highly distributed in a carbon matrix and surrounded by a mesoporous silica layer. Due to their unique confined nanostructure, the Fe/C@mSiO2 capsules could effectively remove and recycle Se(iv) from a low concentration solution.

One-Pot Biosynthesis of Reduced Graphene Oxide/Prussian Blue Microcubes Composite and Its Sensitive Detection of Prophylactic Drug Dimetridazole

Herein, a robust novel electrochemical sensor for the detection of prophylactic drug Dimetridazole (DMZ) has been developed eco-friendly through the green synthesis of reduced graphene oxide/Prussian blue microcubes (rGO/PB MCs), and the fabrication was economically done by efficient screen-printed carbon electrode (SPCE) modification method. It is critical as DMZ excess level in poultry farm imposes carcinogenic threats. A responsive, reproducible and long-lasting DMZ sensor was established using the material composed of Prussian blue microcubes encapsulated by thin sheets of reduced graphene oxide (rGO/PB MCs). The rGO/PB MCs composite is prepared through a facile hydrothermal approach, and its elemental, structural, electrochemical and catalyzing abilities are examined. The composite is fabricated on the SPCE, and the resulting improved electrode showed outstanding electrocatalytic ability toward DMZ and the reduction peak current are correlated to the DMZ concentrations. It retains the more extensive working range between 0.02 μM and 1360.1μM and the detection limit reaches 3.2 nM. It also possesses appreciable sensitivity of 2.2935 μAμM−1cm−2. This technique is efficiently applied to the detection of DMZ in spiked samples of milk and egg.

Formation of Fe2O3 microboxes/ macroporous carbon hybrids from Prussian blue template for electrochemical applications

Iron oxide (Fe2O3) material is considered as a promising catalyst for electrochemical applications. This study reports a design of magnetically Fe2O3 microboxes loaded on macroporous carbon (MPC) hybrids for high-performance electrocatalysts. The obtained Fe2O3 microboxes were converted by decomposition of Prussian blue microcubes (FeIII4[FeII(CN)6]3·nH2O) at a moderate temperature of 350 °C in air. MPC materials with excellent conductivity can offer a platform for the incorporation of Fe2O3 microboxes to form novel hybrid nanostructures with synergetic effects. Because of the unique structural properties and synergetic catalytic effect, a sensitive electrochemical sensor for nitrobenzene was developed based on Fe2O3/MPC, which showed a wide linear range, low detection limit, high sensitivity, and good stability.

Real-time tracking and quantification of endogenous hydrogen peroxide production in living cells using graphenated carbon nanotubes supported Prussian blue cubes

Recent years have seen a growing interest towards real-time tracking and quantification of reactive oxygen species such as, H2O2 released in living cells, as they are potential biomarkers for pathogenesis. Herein, we described a rapid and sensitive enzymeless H2O2 assay using Prussian blue microcubes (PB MCs) decorated graphenated carbon nanotubes (g-CNTs) modified electrode for the tracking of in-vivo H2O2 production in mammalian cells. The hydrothermally prepared PB MCs were blended with g-CNTs to yield 3D hierarchical network of PB MCs/g-CNTs nanocomposite, suitable for efficient electrocatalysis. The g-CNTs/PB MCs film modified electrode was fabricated which displayed excellent electrocatalytic activity to H2O2 reduction at minimized overpotential. A straightforward amperometric sensor was constructed that displayed working range of 25 nM–1598μM, and detection limit of 13nM. The described non-enzymatic H2O2 assay is rapid, sensitive, selective, durable, reproducible and robust. The method was successful in sensing in-vivo H2O2 production from Raw 264.7 cells indicating its potential in biochemical and clinical applications.

1D to 3D hierarchical iron selenide hollow nanocubes assembled from FeSe2@C core-shell nanorods for advanced sodium ion batteries

3D hierarchical hollow nanocubes constructed by 1D FeSe2@C core-shell nanorods were successfully prepared by a thermally-induced selenization process of their Prussian blue microcubes precursor. Such novel nanorods-based FeSe2@C hollow structures exhibit high conductivity and special structural property which provide good charge transport kinetics by facilitating the charge transfer into the inner of FeSe2 nanorods. When used as anode materials for sodium ion batteries, the hierarchically hollow nanocubes showed excellent rate performance and ultra-stable long-term cycling stability at a high current density of 10Ag−1, suggesting a good sodium-ion storage material. This simple solid-phase process demonstrated in this work can be further used for the preparation of other metal selenide with unique and fascinating structure for the potential applications in the energy storage field.

MOFs-derived MgFe2O4 microboxes as anode material for lithium-ion batteries with superior performance

Hollow MgFe2O4 cubic particles are synthesized by using metal organic frameworks (MOFs) Prussian blue microcubes as the self-sacrificial templates, and are used as anode material for lithium-ion batteries. The regular MgFe2O4 microboxes are characterized by ~570 nm in size and shells of ~ 100 nm in thickness, which consists of crystallites with an average size of ~ 24 nm. They display an initial discharge capacity of 1278 mAh g−1 and maintain a discharge capacity of 646 mAh g−1 in the 100th cycle at 50 mA g−1. In addition, MgFe2O4 microboxes show a high discharge capacity of 781 mAh g−1 in the 550th cycle at 1.0 A g−1. They also exhibit a low charge-transfer resistance. The superior cycling and rate performance of MgFe2O4 anodes is attributed to their unique cubic hollow structure with porous shells, which facilitates charge transfer and Li+ diffusion. Additionally, the MgO matrix originated from MgFe2O4 decomposition prevents the agglomeration of active Fe and Fe2O3 tiny particles during cycling.

MgFe2O4 hollow microboxes derived from metal-organic-frameworks as anode material for sodium-ion batteries

Metal-organic-frameworks (MOFs) Prussian blue microcubes are used as the self-sacrificial templates to fabricate hollow MgFe2O4 microboxes via the process of hydrolysis, ion exchange and subsequent calcination. This hollow and porous architecture provides efficient sodium ion diffusion pathway and sufficient space to accommodate the volume expansion during the insertion/extraction of Na+. Obtained MgFe2O4 microboxes exhibit a good capacity of 406mAhg−1 at a current density of 50mAg−1 and maintain a reversible capacity of 135mAhg−1 after 150 cycles when evaluated as an anode material for sodium-ion batteries. With the increase of the amount of Super-P carbon black, the rate performance and conductivity of the MgFe2O4 microboxes electrode can be improved.

Facile synthesis and optical properties of Prussian Blue microcubes and hollow Fe2O3 microboxes

In this paper, we report a novel strategy for the synthesis of Prussian Blue microcubes via hydrothermal conditions by using K3[Fe(CN)6] and glucose for the first time, and then hollow Fe2O3 microboxes have been successfully fabricated by calcination from a Prussian Blue microcube precursors. The phase structures and morphologies were studied using X-ray powder diffraction (XRD), scanning electronic microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and high resolution transmission electron microscopy (HRTEM) with selected area electron diffraction (SAED). The results depict that highly pure and single crystalline monodisperse hollow Fe2O3 microboxes are successfully obtained, which have a diameter ranging from 3 to 5μm. The optical properties of the Prussian Blue microcubes and hollow Fe2O3 microboxes were observed by photoluminescence spectra.

Metal–Organic-Frameworks-Derived General Formation of Hollow Structures with High Complexity

Increasing the complexity of hollow structures, in terms of chemical composition and shell architecture, is highly desirable for both fundamental studies and realization of various functionalities. Starting with metal-organic frameworks (MOFs), we demonstrate a general approach toward the large-scale and facile synthesis of complex hollow microboxes via manipulation of the template-engaged reactions between the Prussian blue (PB) template and different alkaline substances. The reaction between PB microcubes with NaOH solution leads to the formation of Fe(OH)3 microboxes with controllable multishelled structure. In addition, PB microcubes will react with the conjugate bases of metal oxide based weak acids, generating multicompositional microboxes (Fe2O3/SnO2, Fe2O3/SiO2, Fe2O3/GeO2, Fe2O3/Al2O3, and Fe2O3/B2O3), which consist of uniformly dispersed oxides/hydroxides of iron and another designed element. Such complex hollow structures and atomically integrated multiple compositions might bring the usual physiochemical properties. As an example, we demonstrate that these complex hollow microboxes, especially the Fe2O3/SnO2 composite microboxes, exhibit remarkable electrochemical performance as anode materials for lithium ion batteries.