Prussian Blue Nanocubes Research Articles

Prussian blue nanocubes with an open framework structure coated with polyoxometalates as a highly sensitive platform for ascorbic acid detection in drinks/human urine

A novel PB NC@POM platform was constructed and demonstrated high electrochemical response to ascorbic acid due to the excellent synergistic effect.

Novel acetic acid induced Na-rich Prussian blue nanocubes with iron defects as cathodes for sodium ion batteries

Novel Na-enriched Prussian blue with Fe defects is for the first time created, exhibiting sufficient activation of low-spin FeLS(C) redox-couple Na-involved reactions.

Improving Stem Cell Delivery to the Trabecular Meshwork Using Magnetic Nanoparticles

Glaucoma is a major cause of blindness and is frequently associated with elevated intraocular pressure. The trabecular meshwork (TM), the tissue that primarily regulates intraocular pressure, is known to have reduced cellularity in glaucoma. Thus, stem cells, if properly delivered to the TM, may offer a novel therapeutic option for intraocular pressure control in glaucoma patients. For this purpose, targeted delivery of stem cells to the TM is desired. Here, we used magnetic nanoparticles (Prussian blue nanocubes [PBNCs]) to label mesenchymal stem cells and to magnetically steer them to the TM following injection into the eye’s anterior chamber. PBNC-labeled stem cells showed increased delivery to the TM vs. unlabeled cells after only 15-minute exposure to a magnetic field. Further, PBNC-labeled mesenchymal stem cells could be delivered to the entire circumference of the TM, which was not possible without magnetic steering. PBNCs did not affect mesenchymal stem cell viability or multipotency. We conclude that this labeling approach allows for targeted, relatively high-efficiency delivery of stem cells to the TM in clinically translatable time-scales, which are necessary steps towards regenerative medicine therapies for control of ocular hypertension in glaucoma patients.

In situ growth of Prussian blue nanocubes on polypyrrole nanoparticles: facile synthesis, characterization and their application as fiber optic gas sensor

Polypyrrole (PPy) and polypyrrole/Prussian blue (PPy–PB) nanocomposite-based fiber optic gas sensors are developed for gas sensing application. Prussian blue (PB) nanocubes are successfully grown on polypyrrole (PPy) nanoparticles by in situ oxidative polymerization method to obtain PPy–PB nanocomposite. PPy and PPy–PB are evaluated based on structural, morphological and electrical properties. The characteristic peaks present in the FTIR spectra of pure PPy and PB nanoparticles are also present in the FTIR spectrum of PPy–PB nanocomposite with small shifts in the absorption maximum. The XRD pattern reveals the semicrystalline structure of PPy–PB nanocomposite with an average crystallite size of 22 nm, and the morphology (FESEM) shows the formation of PB nanocubes over PPy matrix. AC conductivity measurements show slight improvement in the conductivity value of PPy–PB in comparison with PPy. Dielectric studies in the frequency range of 50 Hz–5 MHz reveal that PPy–PB nanocomposite is a high-k dielectric material. At 50 Hz, PPy–PB exhibits high dielectric constants of 1149 and 766 with low dielectric loss values of 9.9 and 4.6 at 150 and 120 °C, respectively. Further, their application as fiber optic gas sensors in sensing various gases is studied using fiber optic technique. The spectral response is studied for various concentrations (0–500 ppm) of ammonia, acetone and ethanol gases at room temperature. The study shows that the spectral intensity increases linearly with different concentrations of all gases. The clad-modified fiber optic sensor with PPy–PB nanocomposite exhibits enhanced sensitivity for ethanol than clad-modified fiber optic sensor with PPy nanoparticles. TGA studies reveal the high thermal stability of PPy–PB nanocomposite. Hence, PPy–PB-based fiber optic sensors can be used to sense toxic ethanol vapor not only at room temperature but also in a composite environment where a temperature variation is expected.

Human HSP70 Promoter‐Based Prussian Blue Nanotheranostics for Thermo‐Controlled Gene Therapy and Synergistic Photothermal Ablation

AbstractRealizing precise control of the therapeutic process is crucial for maximizing efficacy and minimizing side effects, especially for strategies involving gene therapy (GT). Herein, a multifunctional Prussian blue (PB) nanotheranostic platform is first designed and then loaded with therapeutic plasmid DNA (HSP70‐p53‐GFP) for near‐infrared (NIR) light‐triggered thermo‐controlled synergistic GT/photothermal therapy (PTT). Due to the unique structure of the PB nanocubes, the resulting PB@PEI/HSP70‐p53‐GFP nanoparticles (NPs) exhibit excellent photothermal properties and pronounced tumor‐contrast performance in T1/T2‐weighted magnetic resonance imaging. Both in vitro and in vivo studies demonstrate that mild NIR‐laser irradiation (≈41 °C) activates the HSP70 promoter for tumor suppressor p53‐dependent apoptosis, while strong NIR‐laser irradiation (≈50 °C) induces photothermal ablation for cellular dysregulation and necrosis. Significant synergistic efficacy can be achieved by adjusting the NIR‐laser irradiation (from ≈41 to ≈50 °C), compared to using GT or PTT alone. In addition, in vitro and in vivo toxicity studies demonstrate that PB@PEI/HSP70‐p53‐GFP NPs have good biocompatibility. Therefore, this work provides a promising theranostic approach for controlling combined GT and PTT via the heat‐shock response.

In situ synthesis and characterization of polyaniline/prussian blue/zinc oxide nanocomposite

A new ternary nanocomposite of polyaniline (PANI), prussian blue (PB) and zinc oxide (ZnO), i.e., PANI–PB–ZnO was successfully synthesized in one pot process through chemical oxidative polymerization of aniline using ammonium persulfate as oxidizing agent. The morphological studies showed the formation of PB nanocubes and agglomerated quasi-spherical ZnO nanoparticles over PANI matrix, and the elemental composition of PANI–PB–ZnO was analyzed with energy-dispersive X-ray spectroscopy. The XRD measurements reveal the semicrystalline structure of the PANI–PB–ZnO nanocomposite after the polymerization reaction. The various functional groups present in PANI–PB–ZnO were identified using FTIR spectroscopy which confirms the presence of ZnO, PB and PANI in the synthesized ternary nanocomposite. From thermogravimetric analysis, the thermal degradation mechanism of PANI–PB–ZnO nanocomposite was explored and the activation energy (EA) was calculated from Coats–Redfern plot and was found to be 14.33 kJ/mol. 38 wt% of PANI–PB–ZnO nanocomposite was obtained as a residue at 800 °C indicating the high thermal stability. The bulk ionic conductivity value of the synthesized nanocomposite was found to be 8.509 × 10−5 Ω−1 cm−1 at 30 °C and 1.22 × 10−4 Ω−1 cm−1 at 100 °C. The ionic conductivity was found to increase with temperature for the synthesized material which showed an increase in the number of effective charge carriers. The characteristic absorption bands were detected using UV–Vis spectroscopy that confirms the formation of PANI–PB–ZnO nanocomposite. X-ray photoelectron spectroscopy measurements confirmed the valence states of constituent elements in ZnO nanoparticles and ternary PANI–PB–ZnO nanocomposite. I–V studies revealed that hybrid PANI–PB–ZnO nanocomposite has higher conductivity (2.4 × 10−4 S cm−1) than ZnO nanoparticles (3.5 × 10−10 S cm−1).

Water-Dispersible Prussian Blue Hyaluronic Acid Nanocubes with Near-Infrared Photoinduced Singlet Oxygen Production and Photothermal Activities for Cancer Theranostics.

Design and development of photosensitizers that can efficiently convert energy of near-infrared (NIR) laser irradiation are of major importance for cancer photoassisted therapeutics. Herein, for the first time, it is demonstrated that Prussian blue (PB), a classic coordination compound, can act as a novel photosensitizer with efficient generation of singlet oxygen and excellent photothermal conversion via NIR photoirradiation-induced energy transfer. After modification with hyaluronic acid (HA), the as-prepared HA-modified PB nanocubes (HA@PB) are highly dispersible in aqueous and physiological solutions, as well as show excellent photothermal/photodynamic activities under NIR (808 nm) photoexcitation. On the basis of these features, HA@PB is used to study their in vitro and in vivo combined therapeutic effect. Owing to the CD44 ligand of HA, HA@PB have specific uptake by CD44-positive cells in vitro and can be precisely in vivo delivered to the tumor site. HA@PB as one of the synergistically photodynamic/photothermal combination nanoplatforms could achieve excellent therapeutic efficacy with targeted specificity under the guidance of dual-modality photoacoustic/infrared thermal imaging. Hence, this work is expected to pave the way for using PB-based nanomaterials as a promising multifunctional theranostic nanoplatform in biomedical fields.

Prussian blue nanocubes supported on graphene foam as superior binder-free anode of lithium-ion batteries

The integration of active materials into graphene foam (GF) is of fundamental importance for developing superior binder-free electrodes. In the present design, Prussian blue (PB) nanocubes were uniformly grown into the GF network by a facile immersion approach. This is the first example of GF supported metal cyanides and their applications as electrode materials. The as-prepared PB and GF/PB samples have been characterized systematically. This free-standing and flexible GF/PB composite electrode exhibited a high reversible gravimetric (areal) capacity of 514 mAh g−1 (0.47 mAh cm−2) at 100 mA g−1 over 150 cycles and superior cycling stability with 99% capacity retention as well as good rate capability of ∼150 mAh g−1 at 1 A g−1. Such outstanding electrochemical behaviors were attributed to the synergistic integration of both GF and PB components. Thus, the GF/PB system can be employed as potential superior binder-free anode candidates for high-performance lithium-ion batteries.

A 3D graphene current collector boosts ultrahigh specific capacity in a highly uniform Prussian blue@graphene composite as a freestanding cathode for sodium ion batteries.

For the first time, a uniform graphene aerogel (GA) supported Prussian blue (PB) nanocube structure was synthesized by fitting the nanocube into the GA with a specific pore size and employing it in a freestanding sodium ion battery cathodic electrode. In this electrode, the graphene framework not only offers mechanical support, but also plays the role of a binder-free current collector. The theoretical specific capacity of Prussian blue was exceeded with an ultrahigh specific capacity of 214 mA h g-1 at 0.5 C. With the help of the electronic double layer capacitance of the graphene framework, this ultrahigh value can be achieved. We studied the influence of the mass loading of the PB nanocube on the specific capacity, finding that the GA-induced freestanding electrode has the potential to load a maximum of 72 wt% of the PB nanocube. Furthermore, we separated the capacitance and the capacity of the electrode through kinetic analysis, and discovered that the GA-induced carbon collector contributed to a surface-controlled capacitance, which accounted for 55% of the total capacity.

Ag-HPBs by a coating-etching strategy and their derived injectable implants for enhanced tumor photothermal treatment

Herein, we demonstrate a coating-etching strategy to directly synthesize hollow Prussian blue (PB) nanocubes with well-dispersed Ag nanoparticles (denoted as Ag-HPB). The method is accomplished by introduction of PB precursors, K3Fe(CN)6 and Fe3+ into a reaction system containing AgNO3 and ascorbic acid, in which a series reactions contain formation of Ag nanoparticles, coating of PB on the nanoparticles, and diffusion of Ag into the PB frameworks occur. The strategy for preparation of the hollow structured Ag-HPB is intrinsically simple and does not require pre-preparation of any sacrificial templates or toxic etching agents. The obtained Ag-HPB nanocubes possess uniform size (69 nm), well-defined hollow structure, strong near-infrared photothermal conversion capacity, and excellent photoacoustic and magnetic resonance imaging abilities. Furthermore, an injectable photothermal implants are prepared for the first time by mixing the Ag-HPB nanocubes with clinically used biological glue, which significantly enhance photothermal anti-tumor efficacy, showing great potential for clinical tumor treatment.

Photochemical one-pot synthesis of reduced graphene oxide/Prussian blue nanocomposite for simultaneous electrochemical detection of ascorbic acid, dopamine, and uric acid

Abstract The practical application of Prussian blue (PB) for sensors is still limited due to its electrochemical properties that are dependent on factors such as the low stability at pH close to 7.0, the size and the shape of the material. In this sense, we report a green and facile strategy for one-pot synthesis of reduced graphene oxide/Prussian blue nanocomposites via photochemical method for sensing application. In the proposed method, graphene oxide was reduced simultaneously with the formation of PB nanocubes with controllable size, using sodium nitroprusside as precursor. The nanocomposite is more stable and sensible to electro-reduction of H2O2 when compared to PB at pH 7.4. The observed behavior is due to the ability of graphene to anchor the nanocubes and facilitate the electron transfer between the electrode and PB. Moreover, we also investigated the performance of the nanocomposite for simultaneous detection of ascorbic acid (AA), dopamine (DA) and uric acid (UA). The sensor presented limits of detection of 34.7 μmol L−1, 26.2 μmol L−1, 8.0 μmol L−1, for AA, DA, and UA, respectively.

Effect of light source and applied potential in the electrochemical synthesis of Prussian blue on carbon nanotubes

In this study it was investigated the application of different potentials range and distinct light sources in the formation of Prussian blue (PB) on single walled carbon nanotubes (SWCNT) thin films. The carbonaceous films were deposited through liquid-liquid interface method, with posterior voltammetric cyclic technique been employed for PB deposition and consequent formation of the SWCNT/Prussian blue nanocomposite. The range of applied potential has a great influence on the amount of electrosynthesized PB nanocubes, with the potential window of −0.3 to 1.4V leading to the maximum formation of product. The process of Prussian blue film formation is accelerated by both UVA, UVC and white light radiation. UVA radiation provided the best condition for hexacyanoferrate dissociation, with consequent increase in current and PB deposition. The Prussian Blue/SWCNT films were characterized by different spectroscopic, microscopic, and electrochemical techniques and exhibit high electrochemical stability.

Prussian Blue Nanocubes with an Open Framework Structure Coated with PEDOT as High-Capacity Cathodes for Lithium-Sulfur Batteries.

It is shown that Prussian blue analogues (PBAs) can be a very competitive sulfur host for lithium-sulfur (Li-S) batteries. Sulfur stored in the large interstitial sites of a PBA host can take advantage of reversible and efficient insertion/extraction of both Li+ and electrons, due to the well-trapped mobile dielectron redox centers in the well-defined host. It is demonstrated that Na2 Fe[Fe(CN)6 ] has a large open framework, and as a cathode, it both stores sulfur and acts as a polysulfide diffusion inhibitor based on the Lewis acid-base bonding effect. The electrochemical testing shows that the S@Na2 Fe[Fe(CN)6 ]@poly(3,4-ethylenedioxythiophene) composite achieves excellent reversibility, good stability, and fast kinetics. Its outstanding electrochemical properties should be ascribed to the internal transport of Li+/e- , maximizing the utilization of sulfur. Moreover, the open metal centers serve as the Lewis acid sites with high affinity to the negatively charged polysulfide anions, reducing the diffusion of polysulfides out of the cathode and minimizing the shuttling effect. The fundamental basis of these exceptional performance characteristics is explored through a detailed analysis of the structural and electrochemical behavior of the material. It is believed that the PBAs will have a useful role in ensuring more effective and stable Li-S batteries.

Transformation of Rusty Stainless‐Steel Meshes into Stable, Low‐Cost, and Binder‐Free Cathodes for High‐Performance Potassium‐Ion Batteries

AbstractTo recycle rusty stainless‐steel meshes (RSSM) and meet the urgent requirement of developing high‐performance cathodes for potassium‐ion batteries (KIB), we demonstrate a new strategy to fabricate flexible binder‐free KIB electrodes via transformation of the corrosion layer of RSSM into compact stack‐layers of Prussian blue (PB) nanocubes (PB@SSM). When further coated with reduced graphite oxide (RGO) to enhance electric conductivity and structural stability, the low‐cost, stable, and binder‐free RGO@PB@SSM cathode exhibits excellent electrochemical performances for KIB, including high capacity (96.8 mAh g−1), high discharge voltage (3.3 V), high rate capability (1000 mA g−1; 42 % capacity retention), and outstanding cycle stability (305 cycles; 75.1 % capacity retention).

Transformation of Rusty Stainless-Steel Meshes into Stable, Low-Cost, and Binder-Free Cathodes for High-Performance Potassium-Ion Batteries.

To recycle rusty stainless-steel meshes (RSSM) and meet the urgent requirement of developing high-performance cathodes for potassium-ion batteries (KIB), we demonstrate a new strategy to fabricate flexible binder-free KIB electrodes via transformation of the corrosion layer of RSSM into compact stack-layers of Prussian blue (PB) nanocubes (PB@SSM). When further coated with reduced graphite oxide (RGO) to enhance electric conductivity and structural stability, the low-cost, stable, and binder-free RGO@PB@SSM cathode exhibits excellent electrochemical performances for KIB, including high capacity (96.8 mAh g-1 ), high discharge voltage (3.3 V), high rate capability (1000 mA g-1 ; 42 % capacity retention), and outstanding cycle stability (305 cycles; 75.1 % capacity retention).

In-situ secondary growth of nanocube-based Prussian-blue film as an ultrasensitive biosensor

A regular nanostructure has been widely confirmed to result ina marked improvement in material performance in biosensing applications. In the present study, a regular nanostructured Prussian blue (PB) film with two heterogeneous crystal layers was synthesized in-situ using a secondary growth method. A PB seed layer was first controlled to form uniform cube-like crystal nuclei through an ultrasonic reaction with a single reactant. Then, well-defined 100nm PB nanocubes were further crystallized on this seed layer using a self-assembly approach. In order to accelerate the electron transfer rate during the enzyme reaction for glucose detection, the graphene was used as the main cross-linker to immobilize glucose oxidase on the PB film. The as-prepared biosensor exhibited high electrocatalysis and electron conductivity for the detection of trace glucose with a sensitivity of 141.5μAmM−1cm−2, as well as excellent anti-interference ability in the presence of ascorbic acid and uric acid under a low operation potential of −0.05V.

Prussian blue nanocubes as cathode materials for aqueous Na-Zn hybrid batteries

Abstract Rechargeable aqueous battery is very attractive as a promising alternative energy storage system, based on its safety and environmental-friendly properties. An aqueous rechargeable Na-Zn hybrid battery is assembled by using Prussian blue nanocubes and metallic zinc as cathode and anode, respectively. This Na-Zn cell delivers a high specific capacity of 73.5 mA h g −1 and a good cycling stability (ca. 80% capacity retention after 1000 cycles at 300 mA g −1 ) due to the impressive structure stability of Prussian blue nanocubes. These remarkable features are realized by a simple synthetic method and a feasible battery manufacturing process, which can provide guidance for the development of rechargeable batteries in a large scale.

Three-dimensional hollow CoS2 nanoframes fabricated by anion replacement and their enhanced pseudocapacitive performances

Three-dimensional (3D) hollow CoS2 nanoframes (HCSN) have been fabricated by partial anion replacement of Co-based Prussian blue (PB) nanocubes. The initial self-assembled Co-based PB nanocubes can be converted to hollow Co3[Fe(CN)6]2 nanostructures by corrosion reactions with thioacetamide (TAA) under suitable hydrothermal environment. The pure CoS2 are precipitated simultaneously on the surfaces of hollow Co3[Fe(CN)6]2 nanostructures by ion replacement of [Fe(CN)6]3− in Co-based PB nanocubes with S2− in TAA to form the 3D HCSN. The as-synthesized 3D HCSN exhibit large specific surface area due to their uniform broken hollow structure with good dispersion, which results in their good electrochemical performances including a high specific capacitance of 568Fg−1 at 0.5Ag−1 and good cycling stability with 88.3% specific capacitance retention after 5000 cycles. The asymmetric supercapacitor made from the 3D HCSN can present a high energy density of 32.3Whkg−1 at a power density of 4kWkg−1. These 3D HCSN also shows good structural stability and low density, which further promotes their potential application in high-performance supercapacitors.

Dual-textured Prussian Blue nanocubes as sodium ion storage materials

Sodium ion batteries are being highlighted as a promising energy storage system to resolve the critical issues associated with lithium ion battery usage due to a limited quantity of lithium resources on the earth. Although recent advances in sodium ion battery technology have been remarkable, the reversible capacities and cyclic performance of sodium ion batteries should be further advanced prior to their successful implementation. Herein, we demonstrate dual-textured Prussian blue nanocubes prepared via simple acid etching as a reliable sodium storage material. Taking advantage of their hybrid microstructure composed of porous and non-porous domains, dual-textured Prussian blue nanocubes exhibit high reversible capacities, good rate capabilities, and stable cyclic performance. Moreover, the nanocubes exhibit excellent dimensional stability even after 100 cycles, offering new opportunities for the development of robust and high-performance sodium rechargeable batteries.

Rational design and synthesis of SnO2-encapsulated α-Fe2O3 nanocubes as a robust and stable photo-Fenton catalyst

In situ transformation of metal-organic frameworks (MOFs) is becoming a fascinating strategy to construct porous metal oxides with excellent performance in many fields. In this work, Prussian blue (PB) nanocubes are employed as the precursor of porous Fe2O3 to fabricate SnO2-encapsulated α-Fe2O3 (Fe2O3@SnO2) nanocubes by pre-coating Sn(OH)Cl on the surface of PB nanocubes. It is very interesting to find that SnO2 shells can not only preserve the microstructure of Fe2O3 nanocubes from high-temperature treatment, but also facilitate the phase variation from metastable γ/β-phase to stable α-phase. The thickness of SnO2 shells can be controlled by manipulating the amount of stannous chloride. When Fe2O3@SnO2 nanocubes are applied as heterogeneous photo-Fenton catalysts, they will exhibit much better catalytic efficiency for the degradation of Rhodamine B (RhB) than PB-derived Fe2O3 and commercial α-Fe2O3. The characterization results reveal that Fe2O3@SnO2 nanocubes have similar catalytic mechanism to conventional α-Fe2O3, and stable microstructure and preferable crystalline phase are primarily responsible for this significant enhancement. Some influential factors, including H2O2 concentration, catalyst dosage, pH value, and reaction temperature are investigated and analyzed in details. Moreover, Fe2O3@SnO2 nanocubes can maintain their catalytic efficiency during the repeated batch experiments. We believe Fe2O3@SnO2 nanocubes can be a new kind of high-performance green heterogeneous catalyst for the degradation of organic pollutants, and this study may provide a new idea to upgrade the performance of some conventional catalysts by rational design in the future.