JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
·
2021
·Vol. 40
·期 1
·
IF 2.427
Hsain Hanan Alexandra,Lee Younghwan,Materano Monica,Mittmann Terence,Payne Alexis,Mikolajick Thomas,Schroeder Uwe,Parsons Gregory N.,Jones Jacob L.
Although 10 years have passed since the initial report of ferroelectricity in hafnia (HfO 2 ), researchers are still intensely fascinated by this material system and the promise it holds for future applications. A wide variety of deposition methods have been deployed to create ferroelectric HfO 2 thin films such as atomic layer deposition, chemical solution deposition, and physical vapor deposition methods such as sputtering and pulsed laser deposition. Process and design parameters such as deposition temperature, precursor choice, target source, vacuum level, reactive gases, substrate strain, and many others are often integral in stabilizing the polar orthorhombic phase and ferroelectricity. We examine processing parameters across four main different deposition methods and their effect on film microstructure, phase evolution, defect concentration, and resultant electrical properties. The goal of this review is to integrate the process knowledge collected over the past 10 years in the field of ferroelectric HfO 2 into a single comprehensive guide for the design of future HfO 2 -based ferroelectric materials and devices.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
Crystals
·
2024
·Vol. 14
·期 3
·279
·
IF 2.4
Yang Wu,Hao Lan,Xiaoming Sun,Zihao Hu,Yonghui Sun,Huifeng Zhang,Chuanbing Huang,Weigang Zhang
HfO2has become a promising thermal barrier coating material due to its similarity in structure and chemical properties with ZrO2and its higher phase structure transition temperature. However, the fracture toughness of HfO2is not ideal, greatly limiting its application. In this report, we find a special sandwich structure of ceramics, comprising a cubic (C) phase /monoclinic (M) phase/cubic (C) phase. The microstructural evolution and mechanical properties of these ceramics were investigated under annealing at 1500 °C. The results indicate that, with an increase in annealing duration, there was a gradual augmentation in the proportion of the monoclinic (M) phase and the fracture toughness increased from 2.18 MPa·m0.5to 2.83 MPa·m0.5after 48 h of annealing, which is higher than many potential TBC materials. The residual compressive stress present in the M phases during the progression of crack propagation served to facilitate the bridging and deflection of cracks. As such, this process led to the alleviation of stress concentration at the crack tip, ultimately enhancing the toughening effect.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Jingyu Lin,Xiaohan Wu,Yifan Xia,Lingzhi Nie,Peiyuan Zuo,Puke Mi,Qixin Zhuang
Polyetherimide (PEI) has great potential as a dielectric because of its high-temperature resistance, but its low energy storage density limits practical applications. Incorporating hafnium dioxide (HfO 2 ) with a moderate dielectric constant ( k ) and wide bandgap can simultaneously enhance the polarization intensity of PEI and potential barriers for charge injection . Nevertheless, the poor compatibility between HfO 2 and PEI inevitably introduces defects, thereby weakening the inhibitory effect on dielectric loss . To tackle this issue, an organic double interface layer is introduced to enhance dielectric performance, where the polar poly(arylene ether urea) (PEEU) containing hydrogen bonds can ensure the layer's compactness. Notably, its non-bonding urea groups serve as deep traps to capture migrating carriers, and the gradient k values of HfO 2 , PEEU, and PEI help mitigate electric field distortions at the interface, therefore enhancing the suppression of conduction loss . The polarity of PEEU and the introduction of multiple interfaces significantly contribute to an increased k (maximum 9.7, at 1 kHz). At 300 kV mm −1 , 5 vol% PEEU@HfO 2 /PEI achieves a discharged energy density of 3.3 J cm −3 and a high charge-discharge efficiency of 83 %, surpassing 5 vol% HfO 2 /PEI by 1.95 and 2.44 times, respectively. The further COMSOL simulation verifies and proves this work as a novel design strategy for nanocomposite dielectrics.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Pengju Chen,Tian Tian,Chenzhuo Zhang,Xian Tang,Zhuan Li
A series of Ce-doping nanograin Gd 2 Ce x Hf 2- x O 7 (0.0 ≤ x ≤ 2.0) ceramic samples as nuclear waste forms were prepared, and their microstructure, phase evolution, and aqueous durability were systematically studied. The results revealed that the original Gd 2 Hf 2 O 7 sample comprised a single pyrochlore structure after sintering at 1673 K, but all the Gd 2 Ce x Hf 2- x O 7 (0.5 ≤ x ≤ 2.0) samples assumed defective fluorite structures with Ce-doping. As the x Ce value increased from 0.0 to 2.0, the average grain size of the samples gradually increased from 162 nm to 599 nm, whereas the relative density (measured density/theoretical density) of the samples gradually increased from 91.12% to 93.93%. The normalized release rates of Ce element in the Gd 2 Ce 2 O 7 sample after 42 days were slightly lower than those of Hf element in the Gd 2 Hf 2 O 7 sample owing to the lower porosity of the Gd 2 Ce 2 O 7 sample, and the bond dissociation energy of Ce–O (∼795 kJ/mol) was slightly higher than that of Hf–O (∼791 kJ/mol). Moreover, the normalized release rates of all considered elements were lower than 10 −5 g m −2 d −1 , indicating that the samples had excellent chemical stability.
研究领域:
材料科学
·
核能工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Jingyu Lin,Junhao Jiang,Yukang Zhou,Qianqian Fan,Qixin Zhuang,Puke Mi,Wei Yin,Peiyuan Zuo
Mixing fillers featured with wide band gaps in polymers can effectively meet the requirement of higher energy storage densities. However, the fundamental relationship between the crystal structures of fillers and the dielectric properties of the corresponding nanocomposites is still unclear. Accordingly, we introduced ultralow contents of the synthesized cubic Hafnium dioxide (c-HfO2) or monoclinic Hafnium dioxide (m-HfO2) as deep traps into poly(ether imide) (PEI) to explore their effects on dielectric properties and the charge-blocking mechanism. m-HfO2/PEI showed better charge trapping due to the higher electron affinity and deeper trap energy. At room temperature, the 0.4 vol % m-HfO2/PEI maintains an ultralow dielectric loss of 0.008 while obtaining a dielectric constant twice that of pure PEI at 1 kHz, simultaneously outperforming in terms of leakage current density, breakdown strength (452 kV mm–1), discharge energy density (Ud, 5.03 J cm–3), charge–discharge efficiency (η, 92%), and dielectric thermal stability. At 125 °C, it exhibits a considerable Ud of 2.48 J cm–3 and a high η of 85% at 300 kV mm–1, surpassing the properties of pure PEI. This promising work opens up a new path for studying HfO2-derived dielectrics with unique crystal structures.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Bin Li,Jing Xue,Chao Han,Na Liu,Kaixuan Ma,Ruochen Zhang,Xianwen Wu,Lei Dai,Ling Wang,Zhangxing He
In aqueous zinc-ion batteries, metallic zinc is widely used as an anode because of its non-toxicity, environmental benignity, low cost, high abundance and theoretical capacity. However, growth of zinc dendrites, corrosion of zinc anode, passivation, and occurrence of side reactions during continuous charge-discharge cycling hinder development of zinc-ion batteries. In this study, a simple strategy involving application of a HfO 2 coating was used to guide uniform deposition of Zn 2+ to suppress formation of zinc dendrites. The HfO 2 -coated zinc anode improves electrochemical performance compared with bare Zn anode. Therefore, for zinc-zinc symmetric cells, zinc anode with HfO 2 coating (48 mV) shows lower voltage hysteresis than that of bare Zn anode (63 mV) at a current density of 0.4 mA cm −2 . Moreover, cell with HfO 2 coating also shows good cycling performance in Zn-MnO 2 full cells. At a constant current density of 1.0 A g −1 , discharge capacity of bare Zn-MnO 2 full cell is only 37.9 mAh g −1 after 500 cycles, while that of Zn@HfO 2 -MnO 2 full cell is up to 78.3 mAh g −1 . This good electrochemical performance may be the result of confinement effect and reduction of side reactions. Overall, a simple and beneficial strategy for future development of rechargeable aqueous zinc-ion batteries is provided.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
PubMed
高影响因子
Materials Today Bio
·
2025
·
IF 10.2
Haitao Zeng,Huixiong Feng,Chong Zhang,Zhe Kang,Jianping Wu,Xingqi Zhao,Anfei Huang,Yanyang Xu,Yufeng Huang,Hongwen Xu,Ming Gong
Osteosarcoma (OS) is the most common primary malignant bone tumor in children and adolescents. While radiotherapy is an adjuvant treatment option for OS, particularly in cases of unresectable recurrent metastases, its efficacy remains limited. Enhancing radiosensitivity in OS cells is therefore crucial for improving treatment outcomes. Hafnium oxide, a known radiosensitizer, has demonstrated potential but its current formulation restricts its use to intratumoral administration, posing challenges for treating intraosseous tumors. The development of an intravenous formulation is thus highly desirable. Furthermore, radiotherapy resistance, driven by tumor hypoxia and an immunosuppressive microenvironment, further compromises its effectiveness. In this study, we synthesized hafnium-doped Prussian blue nanoparticles (HP) coated with a tannic acid-manganese metallophenol network (HPTM) to improve biocompatibility and enable intravenous administration. Following intravenous injection in a murine model of OS tibialis in situ tumors with lung metastases, HPTM effectively localized to the primary tumor. Within the acidic tumor microenvironment, manganese was released, activating the STING pathway and triggering anti-tumor immune responses. Moreover, near-infrared light irradiation of the Prussian blue component induced a photothermal effect, promoting apoptosis. Concurrently, under low-dose X-ray irradiation, HPTM augmented radiation energy deposition, generating reactive oxygen species and inducing DNA damage in tumor cells. This synergistic therapeutic approach significantly increased apoptosis in radiotherapy-resistant OS cells, reduced lung metastases, and suppressed primary tumor growth. These findings suggest a promising avenue for clinical translation, integrating radiosensitization, photothermal therapy, and STING pathway activation to overcome current limitations in OS radiotherapy.
研究领域:
肿瘤学
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放射生物学
·
纳米医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Xian Shi,Xinyi Xing,Mengya Ruan,Qichun Wei,Ying Guan,Hui Gao,Siquan Xu
Efficient and green catalysis of cellulose to 5-hydroxymethylfurfural (HMF) is currently a challenge that needs a breakthrough. In this study, a series of inexpensive (x)SO 4 2- /HfO 2 heterogeneous catalysts were prepared and exhibited superior catalytic performance for conversion of cellulose into HMF in the green water-tetrahydrofuran monophasic system (H 2 O-THF). An optimal HMF yield of 54% was acquired through detailed evaluation of reaction conditions. Various analyzes including ICP-OES, XRD, SEM, TEM, FTIR, N 2 adsorption–desorption isotherm, XPS, TG, NH 3 -TPD and Py-FTIR were applied to inspected the physicochemical characteristics of the (x)SO 4 2- /HfO 2 catalysts. Meanwhile, the recyclability of the catalyst and the by-products generated during the reaction process were studied and captured, respectively. The results presented herein show that the catalytic system of (30%)SO 4 2- /HfO 2 catalyst combined with H 2 O-THF monophasic solvent is advanced, and it can be both green and efficient without the presence of other additives and promoters, and has great potential in the future.
研究领域:
化学工程
·
可再生资源转化
✓ 已验证
产品关联
DOI
高影响因子
Nano Express
·
2020
·Vol. 1
·期 3
·030006
·
IF 0
Farooq Ahmad,Tahir Muhmood,Asif Mahmood
Nanoparticles (NPs) are extensively being used in state-of-the-art nano-based therapies, modern electronics, and consumer products, so can be released into the environment with enhancement interaction with humans. Hence, the exposures to these multifunctional NPs lead to changes in protein structure and functionality, raising serious health issues. This study thoroughly investigated the interaction and adsorption of catalase (CAT) with HfO2-NPs by circular dichroism (CD), Fourier transform infrared (FTIR), absorption, and fluorescence spectroscopic techniques. The results indicate that HfO2 NPs cause fluorescence quenching in CAT by a static quenching mechanism. The negative values of Vant Hoff thermodynamic expressions (ΔHo, ΔSo, and ΔGo) corroborate the spontaneity and exothermic nature of static quenching driven by van der Waals forces and hydrogen bonding. Also, FTIR, UV-CD, and UV–visible spectroscopy techniques confirmed that HfO2 NPs binding could induce microenvironment perturbations leading to secondary and tertiary conformation changes in CAT. Furthermore, synchronous fluorescence spectroscopy confirmed the significant changes in the microenvironment around tryptophan (Trp) residue caused by HfO2 NPs. The time depending denaturing of CAT biochemistry through HfO2-NPs was investigated by assaying catalase activity elucidates the potential toxic action of HfO2-NPs at the macromolecular level. Briefly, this provides an empathetic knowledge of the nanotoxicity and likely health effects of HfO2 NPs exposure.
研究领域:
生物化学
·
纳米毒理学
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环境科学
✓ 已验证
DOI
Nanomaterials
·
2022
·Vol. 13
·期 1
·39
·
IF 5.719
Yuan-Dong Xu,Yan-Ping Jiang,Xin-Gui Tang,Qiu-Xiang Liu,Zhenhua Tang,Wen-Hua Li,Xiao-Bin Guo,Yi-Chun Zhou
Resistive random-access memory (RRAM) is a promising candidate for next-generation non-volatile memory. However, due to the random formation and rupture of conductive filaments, RRMS still has disadvantages, such as small storage windows and poor stability. Therefore, the performance of RRAM can be improved by optimizing the formation and rupture of conductive filaments. In this study, a hafnium oxide-/aluminum-doped zinc oxide/hafnium oxide (HfO2/Al-ZnO/HfO2) tri-layer structure device was prepared using the sol–gel method. The oxygen-rich vacancy Al-ZnO layer was inserted into the HfO2layers. The device had excellent RS properties, such as an excellent switch ratio of 104, retention of 104s, and multi-level storage capability of six resistance states (one low-resistance state and five high-resistance states) and four resistance states (three low-resistance states and one high-resistance state) which were obtained by controlling stop voltage and compliance current, respectively. Mechanism analysis revealed that the device is dominated by ohmic conduction and space-charge-limited current (SCLC). We believe that the oxygen-rich vacancy concentration of the Al-ZnO insertion layer can improve the formation and rupture behaviors of conductive filaments, thereby enhancing the resistive switching (RS) performance of the device.
研究领域:
材料科学
·
电气工程
·
纳米技术
·
半导体器件
✓ 已验证
DOI
高影响因子
ACS Nano
·
2024
·
IF 15.8
Yuhua Cao,Shuaishuai Ding,Yunping Hu,Lijuan Zeng,Jingrong Zhou,Ling Lin,Xiao Zhang,Qinghua Ma,Ruili Cai,Yu Zhang,Guangjie Duan,Xiu-wu Bian,Gan Tian
cGAS-STING signaling plays a critical role in radiotherapy (RT)-mediated immunomodulation. However, RT alone is insufficient to sustain STING activation in tumors under a safe X-ray dose. Here, we propose a radiosensitization cooperated with cGAS stimulation strategy by engineering a core–shell structured nanosized radiosensitizer-based cGAS-STING agonist, which is constituted with the hafnium oxide (HfO2) core and the manganese oxide (MnO2) shell. HfO2-mediated radiosensitization enhances immunogenic cell death to afford tumor associated antigens and adequate cytosolic dsDNA, while the GSH-degradable MnO2 sustainably releases Mn2+ in tumors to improve the recognition sensitization of cGAS. The synchronization of sustained Mn2+ supply with cumulative cytosolic dsDNA damage synergistically augments the cGAS-STING activation in irradiated tumors, thereby enhancing RT-triggered local and system effects when combined with an immune checkpoint inhibitor. Therefore, the synchronous radiosensitization with sustained STING activation is demonstrated as a potent immunostimulation strategy to optimize cancer radio-immuotherapy.
研究领域:
癌症生物学
·
纳米技术
·
免疫学
·
放射肿瘤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2023
·
IF 29.4
Dingxin Liu,Fei Cao,Zhifeng Xu,Chunhua Zhao,Zekun Liu,Jiadong Pang,Ze-Xian Liu,Mahdieh Moghiseh,Anthony Butler,Shaoxia Liang,Weijun Fan,Jiang Yang
Radioprotective agents hold clinical promises to counteract off-target adverse effects of radiation and benefit radiotherapeutic outcomes, yet the inability to control drug transport in human organs poses a leading limitation. Based upon a validated rank-based multigene signature model, we evaluate radiosensitivity indices of diverse normal organs as a genomic predictor of radiation susceptibility. We rationally design S elective OR gan- T argeting (SORT) hafnium oxide nanoparticles (HfO 2 NPs) via modulated synthesis by α-lactalbumin, homing to top vulnerable organs. HfO 2 NPs like Hensify are commonly radioenhancers, but SORT HfO 2 NPs exhibit surprising radioprotective effects dictated by unfolded ligands and Hf(0)/Hf(IV) redox couples. Still, the X-ray attenuation patterns allow radiological confirmation in target organs by dual-beam spectral computed tomography. SORT HfO 2 NPs present potent antioxidant activities, catalytically scavenge reactive oxygen species, and mimic multienzyme catalytic activities. Consequently, SORT NPs rescue radiation-induced DNA damage in mouse and rabbit models and provide survival benefits upon lethal exposures. In addition to inhibiting radiation-induced mitochondrial apoptosis, SORT NPs impede DNA damage and inflammation by attenuating activated FoxO, Hippo, TNF, and MAPK interactive cascades. We propose a universal methodology to reverse radioenhancers into radioprotectors. SORT radioprotective agents with image guidance are envisioned as compelling in personalized shielding from radiation deposition. This article is protected by copyright. All rights reserved
研究领域:
辐射生物学
·
纳米技术
·
医学成像
·
分子生物学
·
癌症治疗
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）