JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2022
·
IF 6.76
Zihan Zhou,Yunwen Wu,Huiqin Ling,Jie Guo,Su Wang,Ming Li
3D NAND flash memory with vertically stacked cells has been developed to break through the limits of technology nodes. However, during the selective etching process, it is difficult to ensure the byproducts diffuse away from the trenches in the multistacked layers. Once saturated, the byproduct causes abnormal redeposition on the SiO 2 layers. This problem has restricted the development of high-density 3D NAND memory. To solve this problem, the composition and formation mechanism of the redeposited layer must be clarified. In this study, a ternary-wafer system comprising a Si 3 N 4 /SiO 2 /Si 3 N 4 stack was fabricated to study the redeposition mechanism, and the morphology, elastic properties , and chemical composition of the redeposited layer were clarified. The redeposited layer consists of spherical particles with elastic surfaces (average Young’s modulus of 24.17 GPa). The particles were confirmed to comprise colloidal silica gel covered by silanols . By considering the chemistry of silica , the redeposition mechanism was proposed as follows: colloidal silica gel is formed by the aggregation of silicic acids from Si 3 N 4 etching, which adsorb onto the SiO 2 layer through oxide bridges and hydrogen bonding . Our work will contribute to the development of high-density 3D NAND memory.
研究领域:
微电子学
·
半导体工艺
·
材料科学
·
表面化学
·
纳米材料
·
固态物理
·
集成电路制造
✓ 已验证
DOI
高影响因子
SOLID STATE SCIENCES
·
2018
·
IF 1.861
Jianyi Liu,Yan Liu,Dianxin Jin,Minjia Meng,Yinhua Jiang,Liang Ni,Zhanchao Liu
Tannic-acid-templated large pore mesoporous silica nanoparticle (LMSN) was synthesized using one-pot procedure and the external surface was further modified with APTES (LMSN-N) to immobilize trypsin. After modification, trypsin was difficult to be immobilized on the outer surface of the LMSN due to the electrostatic repulsion. Naturally, study of the trypsin immobilized in the interior pores could be implemented solely. Meanwhile, the activity of immobilized trypsin was optimized by response surface method (RSM), and the ANOVA was employed to explore the interaction between independent variables. The maximum enzyme activity (12.28 U/mg) was obtained under a certain condition that the quality of T-LMSN-N-272 was 153 μg, the pH was 7.9, and the temperature was 40.4 °C. Simultaneously, the immobilized enzyme was proved to possess better thermal stability, storage stability and recycling performance than free enzyme.
研究领域:
生物化学
·
材料科学
·
酶工程
✓ 已验证
产品关联
DOI
高影响因子
Geoscience Frontiers
·
2020
·Vol. 12
·期 2
·957-963
·
IF 4.202
Ruijing Fu,Yaping Chen,Lingrui Wang,Zhiwei Ma,Pengfei Lv,Ying Song,Songrui Yang,Guanjun Xiao,Bo Zou
SiO 2 is the major mineral substance in the upper mantle of the earth. Therefore, studies of the silica-coated materials under high-pressure are essential to explore the physical and chemical properties of the upper mantle. The silica-confined CsPbBr 3 nanocrystals (NCs) have recently attracted much attention because of the improved photoluminescence (PL) quantum yield, owing to the protection of silica shell. However, it remains considerable interest to further explore the relationship between optical properties and the structure of CsPbBr 3 @SiO 2 NCs. We systemically studied the structural and optical properties of the CsPbBr 3 @SiO 2 NCs under high pressure by using diamond anvil cell (DAC). The discontinuous changes of PL and absorption spectra occurred at ∼1.40 GPa. Synchrotron X-ray diffraction (XRD) studies of CsPbBr 3 @SiO 2 NCs under high pressure indicated an isostructural phase transformation at about 1.36 GPa, owing to the pressure-induced tilting of the Pb-Br octahedra. The isothermal bulk moduli for two phases are estimated about 60.0 GPa and 19.2 GPa by fitting the equation of state. Besides, the transition pressure point of CsPbBr 3 @SiO 2 NCs is slightly higher than that of pristine CsPbBr 3 NCs, which attributed to the buffer effect of coating silica shell. The results indicate that silica shell is able to enhance the stabilization without changing the relationship between optical properties and structure of CsPbBr 3 NCs. Our results were fascinated to model the rock metasomatism in the upper mantle and provided a new ‘lithoprobe’ for detecting the upper mantle.
研究领域:
材料科学
·
高压物理
·
纳米材料
·
光学性质
·
地球物理学
✓ 已验证
DOI
高影响因子
RENEWABLE ENERGY
·
2019
·
IF 5.439
Zhao Li,Baorang Li,Xiaoze Du,Hongwei Wu
It is recognized that the thermal performances of the molten salt based nanocomposite can be significantly enhanced. However, there were rare investigations regarding its stability under practical operating thermal environments . In this study, both of the specific heat capacity and thermal diffusivity of the molten salt based nanocomposite were experimentally evaluated under various operating conditions, including that of exposure to constant high temperature and low-high temperature circulation. The typical solar salt based nanofluid was prepared via the modified two-step method. The selected nanoparticle was SiO 2 with an average diameter of 30 nm. Experimental results indicated that both the heat treatments could significantly decrease the thermophysical properties , which would result in poor thermal stability. In comparison with the samples exposing to constant high temperature, the thermal cycled samples showed a more stable thermal property. Further investigations on the SiO 2 particle morphology transition in the process of the heat treatments revealed that the impact of both temperature field and natural convection on particle agglomeration should be responsible for the decrease in thermophysical properties of nanofluid.
研究领域:
材料科学
·
热物理学
·
能源工程
·
纳米科技
·
化学工程
✓ 已验证
DOI
高影响因子
Molecular Catalysis
·
2017
·
IF 0
J. He,X.-H. Lu,Y. Shen,R. Jing,R.-F. Nie,D. Zhou,Q.-H. Xia
Cyclohexanol is an excellent starting material for fuel production, but direct selective hydrogenation of phenol to cyclohexanol under mild conditions is a challenge. Herein we report a catalyst made of Ni nanoparticles supported on high-surface silica, which is highly active for selective formation of cyclohexanol under 1.0 Mpa pressure of hydrogen in aqueous medium without additives. Conversion of 100 mol% and selectivity up to 100% are achieved within 4 h and 1.0 MPa H 2 . Some factors such as the type of the source of silica, the loading of Ni, the reaction temperature and time, the H 2 pressure play important roles in controlling the selective hydrogenation. The generality of the 10%Ni/SiO 2 -1 catalyst for this reaction is demonstrated by selective hydrogenation of other hydroxylated aromatic compounds as well.
研究领域:
催化化学
·
有机合成
·
材料化学
·
绿色化学
·
能源化学
✓ 已验证
DOI
JOURNAL OF THE ENERGY INSTITUTE
·
2021
·
IF 6.186
Dongjing Liu,Lingtao Yang,Bin Li,Jiang Wu
Rice husk , as an abundant agricultural waste and renewable biomass, is adopted to produce porous silica which is used as a potential carbon-free adsorbent for mercury emission control of coal-fired power plants. The rice husk derived porous silica (RHS) exhibits a good Hg 0 adsorption capability with Hg 0 removal efficiency above 80% in the temperature range of 60–140 °C, which is plausibly due to the big specific surface area and mesoporous structure. The mercury removal performance of RHS can be evidently reinforced by KBr modification. The optimal KBr loading value and reaction temperature are 2 wt% and 140 °C, respectively. Acidic gas components, such as NO and SO 2 , both show slight inhibitive effects on Hg 0 adsorption process probably owing to the competitive adsorption or the elimination of adsorption sites.
研究领域:
环境科学
·
大气污染控制
·
材料科学
·
吸附技术
·
能源工程
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Jun Qin,Xiaomei Li,Yunfeng Bai,Feng Feng,Qiliang Pan,Jianguo Zhao
A novel mesoporous silica-deoxycholate (MS-NaDC) synergistic substrate was developed for room-temperature phosphorescence (RTP) sensing and analysis. The substrate exhibited rapid and strong RTP-inducing ability toward 9-bromophenanthrene (9-BrP). The formation mechanism of MS-NaDC synergistic substrate was analyzed and demonstrated. Five MSs with pore size range of 2.73–18.58 nm were synthesized and investigated, and the MS designated as LPMS2 was selected for its rapid RTP protection and good stability in dispersions. RTP in the presence of MS-NaDC substrate also shows good thermostability. Assistant inducers, such as cyclohexane, can be used together for further RTP enhancement. Finally, 9-BrP holds a fairly wide linear concentration range of 2 nM–3 μM, and a detection limit of 0.5 nM. All the results demonstrated the feasibility and application potential of the MS-NaDC substrate in RTP.
研究领域:
分析化学
·
材料科学
·
生物传感器
·
纳米医学
·
分子探针
·
环境监测
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2013
·
IF 2.224
Kejie Yu,Xuebin Zhang,Hongwu Tong,Xiangyan Yan,Shaomin Liu
Fibrous monodisperse core–shell structured Fe 3 O 4 /SiO 2 /KCC-1 nanoparticles were synthesised successfully through a surfactant-templated microemulsion formation process. The structure and morphology of the synthesised nanoparticles were investigated by scanning electron microscopy , transmission electron microscopy , superconducting quantum interference device susceptometer, X-ray diffraction, thermogravimetric analysis and N 2 adsorption/desorption. These nanoparticles showed monodisperse spherical morphology, high magnetism , good thermal stability , large surface area , direct channels, easily accessible large pores and narrow size distribution. A mechanism for the synthesis of these nanoparticles was proposed and explained. Adsorption experiments indicated that the as-prepared materials had good adsorption capacity for dye and could perform a fast transfer of molecules, indicating its promising application in purification of industrial wastewater, drug delivery and so on.
研究领域:
纳米医学
·
材料科学
·
环境工程
·
生物材料
·
药剂学
·
胶体与界面化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2016
·Vol. 42
·期 6
·7767-7773
·
IF 2.758
Shuangbing Li,Jixiao Wang,Song Zhao,Wei Cai,Zhi Wang,Shichang Wang
The unmodified and 3-(trimethoxysilyl) propyl methacrylate (TPM) modified silica nanoparticles were synthesized via the modified Stöber method. The structure and chemical composition of silica nanoparticles were determined by scanning electron microscope (SEM), X-ray diffraction (XRD) characterization, Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results demonstrate that silica nanoparticles with the diameter of 90 nm and amorphous state are successfully modified by TPM. The rheological test results demonstrated that surface modification of nanoparticles and medium exerted great influence on the rheological properties of silica particle suspension. Under high shear rate of about 250 s −1 , the viscosity of suspension comprising unmodified silica nanoparticles and deionized water , TPM-modified silica nanoparticles and deionized water, TPM-modified silica nanoparticles and polyethylene glycol , is about 0.4 Pa.s, 0.1 Pa.s and 30 Pa.s, respectively. The results are significant for preparing homogenous and stable silica nanoparticle suspension, and meaningful for ceramic processing .
研究领域:
材料科学
·
纳米技术
·
陶瓷加工
·
胶体化学
·
高分子材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·Vol. 49
·期 11
·18776-18785
·
IF 5.2
Jiaxu Cheng,Siwei Jiang,Jiahong Fan,Jun Yao,Ning Du,Xue Li,Ding Wang,Peng Dong,Zhongren Zhou,Yingjie Zhang
Molten salt electrolytic synthesis of silicon is identified as a potential industry method due to its thorough deoxidization of oxide and short-flow synthetic progress. However, figuring out a more efficient and sustainable strategy for the increase of the reduction process as well as the control of product morphology still needs endless research. In this study, benefiting from the high electrical conductivity of metallic silver and the easy separation of silver from silver-silicon alloys during the electrolysis of SiO 2 , metallic silver was introduced to electric-catalyze the production of silicon. Firstly, metallic silver was introduced into the silica matrix by a simple silver mirror reaction. Secondly, the mixed Ag\SiO 2 precursor was located at the cathode for molten salt electrolysis . Finally, silicon nanowires were herein achieved in molten NaCl–CaCl 2 . Mechanisms of metal Ag played during the electric-polarization process of silica and the electrochemical nucleation of silicon were further analyzed by X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Field-Emission Scanning Electron Microscope (FESEM), Transmission Electron Microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Raman spectra . The results demonstrate that Ag helps construct Si nanowires via a classic Ag-Si binary alloy-droplet process and provided quantitative guidance for the large-yield production of silicon nanowires via adding 0.08–0.17 g Ag versus 1 g SiO 2 , controlling the temperature at 850–900 °C and electrolysis voltage at 2.6–2.8 V (2.6V at first 1 h and 2.8V at last 5 h). The synthesized silicon nanowires present two types of linear structures based on two three-phase interlines (3PIs) models and a streamed long-straight nanowire is observed.
研究领域:
材料科学
·
纳米科技
·
电化学
·
无机化学
·
能源材料
·
半导体材料
✓ 已验证
DOI
高影响因子
JOM
·
2019
·Vol. 72
·期 6
·2245-2249
·
IF 2.305
Zhang Yannan,Zhang Yingjie,Li Xue,Liu Jiaming,Zhang Mingyu,Yang Xi,Huang Mengyang,Xu Mingli,Dong Peng,Zhou Zhongren
The molten salt electrolytic method was introduced to prepare metallic silicon that simply utilizes SiO 2 powder as the raw material and equimolar CaCl 2 -NaCl as the electrolyte under 1.8 V current at 700°C for 5 h.
The electrochemically synthesized silicon was in the form of nanowire structures with average sizes of 90 nm in diameter and over 1 μm in length. The current efficiency and specific energy consumption of producing silicon nanowires were calculated to be 79.2% and 8.703 kWh/kg, respectively. Benefiting from the synthesized nanowire structure, the silicon anode exhibited a high initial discharge-specific capacity of 3348.1 mAh/g with an initial coulombic efficiency of 85.2%.
The present research provides a straightforward idea to show the feasibility of synthesizing silicon-based material by the molten salt electrolytic method and to introduce the application of synthesized silicon nanowires to lithium-ion battery systems.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
无机合成
✓ 已验证
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 39
·20208-20215
·
IF 3.708
Lei Sun,Xinge Zhang,Jinxia An,Cui Su,Qianqain Guo,Chaoxing Li
Currently, the major challenge for cancer treatment is to develop simple and smart nanocarriers that can efficiently retain the encapsulated drug during blood circulation, recognize tumor cells and quickly release the drug under stimulation. In this paper, such a pH-sensitive core–shell composite nanoparticles is prepared based on a 3-aminophenylboronic acid modified mesoporous silica nanoparticles (MSN–APBA) core coated with a lactobionic acid grafted chitosan (CS–LA) shell via boronate ester bonds. The MSN core increases drug loading capacity and stability, and lactobionic acid offers abundant diols which can form pH sensitive boronate ester bonds with APBA on MSN. Meanwhile, the lactobionic acid-conjugated shell could also efficiently target the asialoglycoprotein receptor over expressing hepatoma cells. The successful synthesis of CS–LA and MSN–APBA is confirmed by the results of TGA, TEM, DLS, FT-IR, 1H-NMR and N2 adsorption–desorption. Doxorubicin hydrochloride (DOX) is applied as a model drug and the behaviors of drug loading/release are investigated. The drug loading behavior is pH-dependent, and its drug encapsulation efficiency is near 80% and loading capacity is 13.05%. The results of cumulative in vitro release indicate that at neutral pH, the pores of the MSN are effectively capped with a polymer shell and the drug release is strongly inhibited, almost zero release. While at acidic pH, the hydrolysis of the boroester bond takes place and thus results in a rapid release of the entrapped drug. The cytotoxicity assay indicates high cell biocompatibility of this material and it is suitable as a drug carrier. When loaded with DOX, it presents distinctly cytotoxic behavior to HepG2 cells, due to the sustained release of drug. These results imply that the core–shell nanoparticles are promising platforms to construct simple and effective pH-responsive controlled drug delivery systems for cancer therapy.
研究领域:
肿瘤学
·
药剂学
·
纳米医学
·
生物材料
·
分子药理学
·
靶向治疗
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）