BaTiO3 Nanoparticles Research Articles

Effect of Average Grain Size on the Uniformity and Ferroelectricity of BTO/PSX Thin Films Processed by Low-Temperature Solution Method.

In this study, we utilized 50 nm BaTiO3 (BTO) nanoparticles and polysiloxane (PSX) with a higher concentration of methyl and silica groups to fabricate insulating layers at a low curing temperature of 100 °C using a solution-based method. This approach aims to enhance film uniformity while retaining the ferroelectric properties. Consequently, we maintained a minimal leakage current in thin-film transistors (TFTs) while achieving transfer characteristics characterized by a distinct hysteresis. Moreover, we verified the presence of ferroelectricity in 50 nm BTO nanoparticles. Compared with prior research, we confirm that decreasing nanoparticle size effectively reduces film roughness but also leads to a reduction in polarization intensity due to smaller diameter BTO nanoparticles. Additionally, a higher proportion of methyl and silica groups effectively lowers the curing temperature of PSX. At the same time, the hydrogen ions released in the polycondensation reaction can also effectively suppress the oxygen vacancies at the interface between dielectric and channel layers, improving the TFT electrical characteristics.

Harnessing the Power of Nano‐Ferroelectrics: BaTiO3/MXene (Ti3C2Tx) Composites for Enhanced Lithium Storage

Abstract2D Ti3C2Tx MXene is a desirable electrode material for advanced lithium‐ion batteries (LIBs) in the pursuit of high energy and power densities, owing to its extensive reactive area and surface‐induced pseudo‐capacitance. Here, a novel synergistic strategy for fortifying lithium storage capability is first proposed, by in‐situ anchoring BaTiO3 ferroelectric nanoparticles on few‐layered Ti3C2Tx nanosheets (BT/f‐Ti3C2Tx) using a hydrothermal method. The uniform BaTiO3 nanoparticles effectively prevent the restacking of Ti3C2Tx nanosheets, successfully deplete metastable Ti atoms, and intriguingly form a thin and well‐adhered solid electrolyte interface layer, enhancing the aggregation‐resistant, oxidation‐resistant, and electrochemical properties of Ti3C2Tx. Simultaneously, the internal electric fields, originating from the spontaneous polarization of BaTiO3 ferroelectric nanoparticles, can augment the adsorption of Li+, boosting the lithium storage capacity and reaction kinetics. The resulting composite electrode displays a remarkable charge capacity of 84 mAh g−1 at 10 A g−1, almost five times that of pristine Ti3C2Tx electrode. The excellent rate performance and cyclability make BT/f‐Ti3C2Tx composites highly attractive for LIBs. Furthermore, this synthetic approach presented here is scalable and can be extended to other Ti‐based materials. This strategy is expected to underscore the considerable potential of ferroelectric composites for integration into high‐performance LIBs.

The effect of the acceleration voltage on the quality of structure determination by 3D-electron diffraction

Nowadays, 3D Electron Diffraction (3DED) is widely used for the structure determination of sub-micron-sized particles. In this work, we investigate the influence of the acceleration voltage on the quality of 3DED datasets acquired on BaTiO3 nanoparticles. Datasets were acquired using a wide range of beam energies, from common, high acceleration voltages (300 kV and 200 kV) to medium (120 kV and 80 kV) and low acceleration voltages (60 kV and 30 kV). It was observed that, in the integration process, Rint increases as the beam energy is reduced, which is mainly due to the increased dynamical scattering. Nevertheless, the structure was solved successfully in all cases. The structure refinement was comparable for all beam energies with small deficiencies such as negative atomic displacements for the heaviest atom in the structure, barium. Including extinction correction in the refinement noticeably improved the model for low acceleration voltages, probably due to higher beam absorption in these cases. Dynamical refinement, however, shows superior results for higher acceleration voltages, since the dynamical refinement calculations currently ignore inelastic scattering effects.

Evaluation of X-ray radiation shielding performance of Bi2O3 and BaTiO3 embedded in PVP and PEG polymer nanocomposite

This study addressed the limitations of lead-based radiation shields by developing lead-free, non-toxic, lightweight, and flexible shielding materials with high attenuation efficiency. To achieve this, single and triple layers of Bi2O3-BaTiO3/PVP-PEG nanocomposite films were synthesized. Polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) polymers (2:1 ratio) were used as the polymeric matrix in which fillers of Bi2O3 and BaTiO3 nanoparticles (NPs) with particle sizes ranging from 90 to 210 nm and <100 nm, respectively, were embedded. Four single-layer samples with 20%, 30%, 40%, and 50% NP concentrations were prepared; the samples were 1.05, 1.09, 1.27, and 1.42 mm thick, respectively. Two samples of triple-layered films were prepared with 30% and 50% NPs, measuring 3.78 and 4.23 mm in thickness, respectively. The attenuation efficiency of these films was investigated using X-ray tube voltages from 10 to 120 kVp. Further, the flexibility of the synthesized films was tested by manual handling. All single- and triple-layer nanocomposites exhibited effective radiation attenuation and desirable flexibility. Specifically, at the lowest tube voltage, all samples exhibited 100% attenuation, while at the highest tube voltage, the attenuation ranged from 27% to 84%, depending on the NP concentration and number of layers of the sample. The highest attenuation ratio, observed in the 50% triple-layer sample, reached 100% up to approximately 60 kVp and 84% at 120 kVp. Consequently, the most optimal film synthesized in this study had a triple-layer configuration with 50% Bi2O3-BaTiO3 NPs embedded in a PVP-PEG polymer with an average attenuation of 95.5% for all tube voltages (10–120 kVp). Therefore, this shielding is suitable for various diagnostic applications, such as mammography, dental X-rays, computerized tomography, and fluoroscopy. Highlights Single- and triple-layered nanocomposite Bi2O3-BaTiO3/PVP-PEG films were synthesized The attenuation efficiency of the films against X-rays was investigated A triple-layer configuration with 50% Bi2O3-BaTiO3/PVP-PEG was suitable for various diagnostic applications

Enhanced photocatalytic efficiency of BaTiO3 augmented by ZnS nanospheres via Type-II heterojunction for methyl orange degradation

The degradation of organic pollutants is significantly influenced by the recombination of photogenerated electron–hole pair, electron transfer and surface area of a photocatalyst. Barium titanate (BaTiO3) exhibits low photocatalytic activity due to the rapid recombination of photoinduced charge carriers. Hence, the photocatalytic performance of BaTiO3 (BTO) nanoparticles was improved by the construction of heterostructure with the addition of ZnS. BaTiO3 and ZnS were prepared using solid-state metathesis (SSM) and hydrothermal methods, respectively. Subsequently, a series of [(1-x)BaTiO3/(x)ZnS, x = 10, 30, 50 and 70 wt%] heterostructures were successfully constructed through a simple calcination method using pre-prepared BaTiO3 and ZnS. The XRD, FTIR, Raman, XPS and HRTEM analyses revealed the formation of heterostructure between the BTO and ZnS. The positron annihilation lifetime spectroscopy (PALS) results suggest the existence of defects within the materials. To explore the photocatalytic activity, the photodegradation of methyl orange (MO) dye was carried out under UV light illumination for 3 h. Among all the compositions, the heterostructure 70 BaTiO3/30 ZnS (BTZS(70-30)) demonstrated remarkable photocatalytic activity (91.38 %) which is 5.3 times higher than the pristine BTO (17.16 %). The improved photocatalytic activity of heterostructures may result from the effective charge carrier separation facilitated by the type –II band alignment structure between BTO and ZnS, as well as surface defects like oxygen (Vo), and sulphur (Vs) vacancies. The lowest photoluminescence of BTZS (70-30) clearly substantiated the observed high photocatalytic activity. The scavenger outcomes validated that superoxide radicals (•O2−) and holes (h+) played predominant role in the degradation of MO and a detailed explanation was provided for the plausible mechanism.

Enhancement of α to β phase transformation in poly (vinylidene fluoride) nanocomposites under uni-axial stretch: Contribution from restriction of nano-particles

Electroactive polyvinylidene fluoride (PVDF) with predominantly the β-phase is now challenging the fabricating of PVDF toward energy storage applications. Here, the comprehensive effect of BaTiO3 nano-particles and mechanical stretching on the improvement of the β-phase of PVDF was investigated. In situ synchrotron wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) measurements were performed to investigate this behavior. Consequently, the transformation rate of β-crystal for both pure PVDF (BT0) and PVDF/BaTiO3 (90/10) nanocomposites (BT1) decreases as the stretching temperature increases, implying that the high temperature is unfavorable to the formation of β-crystal phase. A synergistic enhancement of the β-phase of nano-particle additives and stretching was discovered. It was surprisingly observed that α-phase of PVDF would completely transform into β-crystal in BT1 sample at 100 °C during stretching. The mechanism of the synergistic effect of BaTiO3 nano-particles and mechanical stretching was proposed. Moreover, machine learning was implemented to predict the fraction of β-crystal phase (F(β)) of the PVDF/BaTiO3 composites under various uni-axial stretching conditions by Python 3.8. The results show that the machine learning technique can rapidly and efficiently discover the ideal value of F(β) and the optimal multivariate coupling conditions.

Polypropylene nanocomposite film with enhanced energy storage performance via a continuous preparation

Dielectric polymers have been extensively employed in renewable energy conversion, hybrid electric vehicle, and high voltage direct current transmission systems, owing to their excellent electrical insulation, processability, and self-healing capability. However, the challenge lies in their relatively low dielectric constant (εr) and limited discharge energy density (Ue), which hinder the advancement of integrated power modules. Despite numerous efforts aimed at enhancing Ue, the fabrication of scalable dielectric film with both enhanced Ue and high charge–discharge efficiency (η) remains a major obstacle. Herein, the polypropylene-based films with BaTiO3@PP-g-MAH (BTO@PP-g-MAH) core–shell nanoparticles are prepared through a continuous melt extrusion process. The resulting nanocomposite film, incorporated with 5 wt% BTO@PP-g-MAH, exhibits an impressive Ue of 5.15 J cm−3 and achieves a high η of 93.2 % at 433 MV m−1, along with excellent cycle dielectric stability. Such enhancements in εr and Ue are ascribed to the improved interfacial polarization facilitated by BaTiO3 nanoparticles and the enhanced interface binding achieved through the PP-g-MAH shell layers. Furthermore, the enhancement of electric breakdown strength (Eb) is comprehensively investigated based on electrical breakdown mechanism and electromechanical breakdown model. This study demonstrates a novel strategy to prepare nanocomposite dielectric films that are compatible with commercial capacitor fabrication process.

Properties of BaTiO3 nanoparticles based on FTIR derived using Nephelium lappaceum L. leaf extract

The properties of barium titanate (BaTiO3) nanoparticles synthesized with rambutan leaf extract (Nephelium lappaceum L.) were analyzed using Fourier transform infrared spectroscopy (FTIR) characterization techniques. Rambutan leaf extract contains bioactive compounds that have the potential to enhance unique physical and chemical properties. This study aims to analyze the properties of the nanoparticles and to characterize the functional groups present in BaTiO3 nanoparticles synthesized using rambutan leaves. The nanoparticle synthesis process involved extraction, followed by the preparation of a BaTiO3 solution and doping. The FTIR spectrum displayed characteristic peaks identifying the presence of functional groups. The results indicated that the region 3500 – 3200 cm-1 corresponds to O–H groups (alcohol and phenolic), the region 1700 – 1600 cm-1 to C=O groups (carbonyl), the region 1600 – 1500 cm-1 to C=C groups (alkene), and the region 1200 – 1000 cm-1 to C–O groups (ether). Each functional group exhibits distinct properties.

FTIR characterization analysis of BaTiO3 nanoparticles synthesized using Terminalia catappa leaf extract

Ferroelectric materials are materials that are in great demand in high-density memory applications, such as ferroelectric random access memory, ferroelectric field effect transistors, negative capacitance field effect transistors, and ferroelectric tunnel junctions. Barium titanate (BaTiO3) is a lead-free ferroelectric material with a high dielectric constant and low dielectric loss. The method used is sol gel for the synthesis of BaTiO3 solution, extract for ketapang (Terminalia catappa) leaves, and characterized by FTIR. The FTIR spectrum synthesized with ketapang leaf extract displays several characteristic peaks in the mid-infrared region (4000 – 400 cm-1). These peaks can be determined by the specific vibration mode of the structure and organic compounds contained in the ketapang leaf extract. BaTiO3 has a cubic perovskite structure with a peak wave number of 600 cm-1. Ketapang leaf extract is incorporated into the BaTiO3 structure. BaTiO3 has a Ti–O functional group. Ketapang leaf extract has C–O, C=O, C–H, and O–H functional groups.

Preparation and piezoelectric assisted photocatalytic degradation of BaTiO3/SrTiO3 nanocomposites

Piezoelectric materials capable of generating an inherent electric field under strain, exhibit promising applications in in-situ piezocatalysis and enhanced photocatalytic activities. SrTiO3 (STO) is a photocatalytic material, but it faces challenges such as low efficiency in photogenerated carrier separation and transfer, as well as limited reduction and oxidation reactions. To address these issues, this study utilized the piezoelectric properties of tetragonal BaTiO3 (BTO) nanoparticles and the photocatalytic properties of STO to prepare BaTiO3/SrTiO3 composite materials for piezoelectric assisted photocatalytic degradation of dyes. Disperse BTO nanoparticles with different mass ratios in STO spinning solution to produce a suspension, which is electrospun to form BTO-STO-1:x. The optimal degradation performance and catalytic activity of BTO-STO-1:x were determined through testing to identify the best composite material. It provides a robust foundation for underpinning the coupling mechanism between the enhancement of piezoelectricity and photocatalytic effect, offering an efficient pathway for advancing the field of piezoelectric assisted photocatalysis.

Simultaneous Second Harmonic Generation and Multiphoton Excited Photoluminescence in Samarium-Doped BaTiO3 Nanoparticles Functionalized with Poly(ethylene glycol).

In this work, samarium-doped BaTiO3 (BT:Sm) nanoparticles (NPs) were prepared and coated with poly(ethylene glycol) (PEG) to investigate their optical characteristics and compatibility with biological systems. The structure, particle morphology, optical properties, and biological compatibility of the NPs were assessed. The results demonstrated the formation of BT:Sm and [(BT:Sm)-PEG]. The relative intensities and positions of peaks in the X-ray diffraction (XRD) are consistent with an average crystallite size of ∼75 nm. The Raman spectra showed that Sm doping produced the typical tetragonal peaks at around 306 and 715 cm-1, and Fourier transform infrared (FTIR) spectroscopy showed that the PEGylation process was effective. Also, our investigation demonstrates the potential of these NPs as very temperature-sensitive nanosensors with a resolution exceeding 0.5 °C, which is achievable through optical excitation. We also analyze their emission properties. Finally, we present a study related with the mitochondrial activity of naked and PEG-coated NPs. The results indicate that neither naked nor PEG-coated NPs exhibit changes in mitochondrial metabolism, as indicated by quantitative cell viability and morphological visualization. The PEG-coated NPs prevented the formation of aggregates in cell culture compared to naked NPs, demonstrating the significance of PEG as a stabilizing agent.

Development, Dielectric Response, and Functionality of ZnTiO3/BaTiO3/Epoxy Resin Hybrid Nanocomposites

In the present work, hybrid nanocomposites of an epoxy resin reinforced with ZnTiO3 and BaTiO3 nanoparticles, at various filler contents, were fabricated and studied. The successful integration of ceramic nanofillers and the fine distribution of nanoparticles were confirmed via X-ray Diffraction patterns and Scanning Electron Microscopy images, respectively. Dielectric properties and related relaxation phenomena were investigated via Broadband Dielectric Spectroscopy in a wide range of frequencies and temperatures. Data analysis showed that dielectric permittivity increases with filler content, although optimum performance does not correspond to the maximum ZnTiO3 content. Four relaxation processes were observed and attributed to interfacial polarization (IP) (at low frequencies and high temperatures), glass-to-rubber transition (α-relaxation) of the epoxy matrix (at intermediate frequencies and temperatures), and local rearrangements of polar side groups of the macromolecules (β-relaxation) and small flexible groups of the main polymer chain (γ-relaxation) occurring at low temperatures and high frequencies. The ability of hybrid nanocomposites to store and retrieve energy was studied under dc conditions by employing a charging/discharging sequence. The stored and retrieved energy increases with filler content and charging voltage. The optimum ability of energy recovering, shown by the epoxy/7 phr ZnTiO3/7 phr BaTiO3 nanocomposite, ranges between 30 and 50 times more than the matrix, depending on the time instant. The employed nanoparticles induce piezoelectric properties in the nanocomposites, as found by the increase in the piezoelectric coefficient with filler content.

Reprocessing, shape recovery and dielectric properties of nanocomposites of Polyhydroxyurethane with barium Titanate

Poly(N-vinyl pyrrolidone) (PVPy) chains were grafted onto the surfaces of barium titanate (BaTiO3) nanoparticles via the surface-initiated living/controlled radical polymerization of N-vinyl pyrrolidone. The PVPy-grafted BaTiO3 nanoparticles were then incorporated into a crosslinked polyhydroxyurethane (PHU) which was derived from bis(six-membered) cyclic carbonate and a triamine (i.e., Jeffamine T400). It was found that BaTiO3 nanoparticles were uniformly dispersed into the PHU matrix. The generation of nanocomposites resulted that the glass transition temperatures (Tg’s) and mechanical properties were significantly enhanced. In the meantime, the nanocomposites had the dielectric properties superior to control PHU; the shape memory properties of the materials were significantly improved in terms of response, fixity of transient shape and recovery of the original shapes. Thanks to transcarbamoylation of hydroxyurethane structural units, the crosslinked nanocomposites can be reprocessed at elevated temperature. It was found that dibutyltin dilaurate (DBTDL) was an effective catalyst to decrease the Arrhenius activation energy of the dynamic reaction; the reprocessing of the nanocomposites can be carried out at the temperature as low as 120 °C.

Piezoelectric stimulation enhances bone regeneration in alveolar bone defects through metabolic reprogramming of macrophages

AbstractImmunomodulation has emerged as a promising strategy for promoting bone regeneration. However, designing osteoimmunomodulatory biomaterial that can respond to mechanical stress in the unique microenvironment of alveolar bone under continuous occlusal stress remains a significant challenge. Herein, a wireless piezoelectric stimulation system, namely, piezoelectric hydrogel incorporating BaTiO3 nanoparticles (BTO NPs), is successfully developed to generate piezoelectric potentials for modulating macrophage reprogramming. The piezoelectric stimulation reprograms macrophages towards the M2 phenotype, which subsequently induces osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). RNA sequencing analysis reveals that piezoelectricity‐modulated macrophage M2 polarization is closely associated with metabolic reprogramming, including increased amino acid biosynthesis and fatty acid oxidation. The composite hydrogel with excellent biocompatibility exhibits immunomodulatory and osteoinductive activities. In a rat model of alveolar bone defects, the piezoelectric hydrogel effectively promotes endogenous bone regeneration at the load‐bearing sites. The piezoelectric‐driven osteoimmunomodulation proposed in this study not only broadens understanding of the mechanism underlying piezoelectric biomaterials for tissue regeneration but also provides new insights into the design and development of next‐generation immunomodulatory biomaterials.

Enhanced triboelectricity through visible-light-induced surface charges in BTO-polymer hybrid for coexistence solar-mechanical energy harvesting

The exploration of hybrid composites holds great promise in the pursuit of synergistic energy-harvesting solutions, providing an efficient approach to tap into multiple energy sources. One striking example is the BTO (BaTiO3)-polymer hybrid where its high dielectric constant and the piezo-/ferroelectricity are leveraged to improve the triboelectricity of the polymer-based triboelectric nanogenerator (TENG). Beyond this, the BTO also exhibits a photoactive nature, which, until now, has not been exploited to enhance triboelectricity. In this study, a facile method to exploit BTO’s photoresponses in a BTO-polymer hybrid is reported, where surface states present in BTO nanoparticles enable visible spectrum absorption, and the interfaces are designed to facilitate charge spatial separation. Upon visible light illumination, surface charges are generated on the BTO-polymer hybrid, significantly enhancing the photo-induced charge electrification, which in turn boosts the TENG output. These findings demonstrate the possibility of simultaneously harvesting solar and mechanical energies in TENGs using ceramic-polymer hybrids. Additionally, the study employs multiple advanced Scanning Probe Microscopy (SPM) techniques to elucidate the roles of each component and interface in energy harvesting, shedding light on the functional material design. This work not only broadens the variety of energy sources for TENGs but also addresses the growing demand for sustainable and adaptable methods of power generation.

Efficient Electrical Extraction of Nonlinear Response and Large Linear Dynamic Range Implementation in MoS2/BaTiO3 Hetero‐Integrated Photodetector

AbstractConventional photodetectors overly pursue high light‐to‐electric conversion efficiency under weak light stimulation, while disregarding the saturated absorption‐induced blinding effect upon strong light, and achieving efficient photodetection covering a large power range remains a great challenge. In this work, MoS2/BaTiO3 heterostructures are constructed through a low‐cost exfoliation and transfer method combined with spin‐coating. The photoresponse behaviors before and after assembling the BaTiO3 nanoparticles onto the MoS2 nanoflake are investigated, indicating that the high conductivity of MoS2 and ferroelectricity of BaTiO3 can complement each other to improve the photoresponse of the hetero‐integrated device, acquiring a high photoresponsivity of 17402 A W−1 under 0.2 nW irradiation, and a significant 570 µA photocurrent under 8 mW irradiation, realizing a large linear dynamic range index of 152 dB, which is at the top level among layered semiconductor‐based detectors. Moreover, strong power near‐infrared light can be up‐converted to the visible band through the nonlinear effect of BaTiO3, subsequently absorbed by the MoS2 and contributing to the photocurrent, providing a solution to combat and alleviate the saturated absorption issue in photodetection. This work marks a significant advancement in achieving robust high‐performance photodetection by hetero‐integrating 2D materials with ferroelectrics.

Ag Nanoparticles Deposited onto BaTiO3 Aerogel for Highly Efficient Photodegradation.

Given the increasingly severe environmental problems caused by water pollution, the degradation of organic dyes can be effectively achieved through the utilization of photocatalysis. In this work, metal alkoxides and a combination of alcohol/hydrophobic solvents are employed to prepare BaTiO3 aerogels via a liquid-phase and template-free synthetic route. The preparation process of the aerogels solely entails facile agitation and supercritical drying, eliminating the need for additional heat treatment. The binary solvent of ethanol and toluene is identified as the optimal choice, resulting in a significantly enhanced surface area (up to 223 m2/g) and an abundant pore structure of BaTiO3 aerogels compared to that of the BaTiO3 nanoparticles. Thus, the removal efficiency of the BaTiO3 aerogel sample for MO is nearly twice as high as that of the BaTiO3 nanoparticles sample. Noble metal Ag nanoparticles' deposition onto the BaTiO3 aerogel surface is further achieved via the photochemical deposition method, which enhances the capture of photogenerated electrons, thereby ensuring an elevated level of photocatalytic efficiency. As a result, Ag nanoparticles deposited on BaTiO3 aerogel can degrade MO completely after 40 min of illumination, while the corresponding aerogel before modification can only remove 80% of MO after 60 min. The present work not only complements the preparatory investigation of intricate aerogels but also offers a fresh perspective for the development of diverse perovskite aerogels with broad applications.

BaTiO3 Catalyzed Ultrasonic-Driven Piezoelectric-Induced Reversible Addition-Fragmentation Chain-Transfer Polymerization in Aqueous Media.

Compared with normal stimulus such as light and heat, ultrasonic possesses much deeper penetration into tissues and organs and has lower scattering in heterogeneous systems as a noninvasive stimulus. Reversible addition-fragmentation chain-transfer polymerization (RAFT) in aqueous media is performed in a commercial ultrasonic wash bath with 40kHz frequency ultrasonic, in the presence of piezoelectric tetragonal BaTiO3 (BTO) nanoparticles. Owing to the electron transfer from BTO under the ultrasonic action, the water can be decomposed to produce hydroxyl radical (HO•) and initiate the RAFT polymerization (piezo-RAFT). The piezo-RAFT polymerization exhibits features of controllable and livingness, such as linear increase of molar mass and narrow molar mass distributions (Mw/Mn < 1.20). Excellent temporal control of the polymerization and the chain fidelity of polymers are illustrated by "ON and OFF" experiment and chain extension, separately. Moreover, this ultrasonic-driven piezoelectric-induced RAFT polymerization in aqueous media can be directly used for the preparation of piezoelectric hydrogel which have potential application for stress sensor.

Biomimetic-inspired piezoelectric ovalbumin/BaTiO3 scaffolds synergizing with anisotropic topology for modulating Schwann cell and DRG behavior

The treatment of peripheral nerve injury is a clinical challenge that tremendously affected the patients' health and life. Anisotropic topographies and electric cues can simulate the regenerative microenvironment of nerve from physical and biological aspects, which show promising application in nerve regeneration. However, most studies just unilaterally emphasize the effect of sole topological- or electric- cue on nerve regeneration, while rarely considering the synergistic function of both cues simultaneously. In this study, a biomimetic-inspired piezoelectric topological ovalbumin/BaTiO3 scaffold that can provide non-invasive electrical stimulation in situ was constructed by combining piezoelectric BaTiO3 nanoparticles and surface microtopography. The results showed that the incorporation of piezoelectric nanoparticles could improve the mechanical properties of the scaffolds, and the piezoelectric output of the scaffolds after polarization was significantly increased. Biological evaluation revealed that the piezoelectric topological scaffolds could regulate the orientation growth of SCs, promote axon elongation of DRG, and upregulate the genes expression referring to myelination and axon growth, thus rapidly integrated chemical-mechanical signals and transmitted them for effectively promoting neuronal myelination, which was closely related to peripheral neurogenesis. The study suggests that the anisotropic surface topology combined with non-invasive electronic stimulation of the ovalbumin/BaTiO3 scaffolds possess a promising application prospect in the repair and regeneration of peripheral nerve injury.

BaTiO3 catalyzed ultrasonic driven piezoelectric induced miniemulsion atom transfer radical polymerization (Piezo-miniATRP)

Compared with other stimulus such as light and heat, ultrasonic possesses much deeper penetration into tissues and organs and has lower scattering in heterogeneous systems as a noninvasive stimulus, and has already been used as the external stimulus to initiate reversible-deactivation radical polymerization (RDRP). However, the development of efficient ultrasonic drive RDRP in aqueous dispersed media remains a challenge. Here in this work, ultrasonic driven piezoelectric induced miniemulsion atom transfer radical polymerization (Piezo-miniATRP) was performed, with tetragonal BaTiO3 (BTO) nanoparticles as the piezoelectric catalyst. The Piezo-miniATRP exhibited features of controllable and livingness, such as linear increase of molar mass and narrow molar mass distributions (Mw/Mn < 1.30). The effect of different polymerization parameters on the polymerization reaction was investigated, including the amounts of surfactant, CuBr2 and BTO dosages. Excellent temporal control of the polymerization and the chain fidelity of polymers were illustrated by “ON and OFF” experiment and chain extension, separately. This novel BTO catalyzed Piezo-miniATRP process could also be extended to other aqueous dispersion RDRP systems.