International Journal of Applied Ceramic Technology
·
2024
·Vol. 22
·期 1
·e14882
·
IF 1.8
Yifei Dai,Yuxuan Liao,Aoping He,Huan He,Tianquan Liang
The hot corrosion behaviors of the Sc 2 O 3 –Gd 2 O 3 –Y 2 O 3 co-doped ZrO 2 (SGYSZ) ceramics in Na 2 SO 4 + V 2 O 5 molten salts at high temperature were investigated in this work. The results show that the SGYSZ exhibits good hot corrosion resistance to the 50 wt% Na 2 SO 4 + 50 wt% V 2 O 5 molten salts at 1000°C. It is attributed to the doping of small Sc 3+ , which can decrease the M–O bonding length and increase the binding energy, and then reduce the dissolution and loss of the stabilizer as rare-earth cations Gd 3+ and Y 3+ from the SGYSZ. The significant synergistic effects of Sc 3+ , Gd 3+ , and Y 3+ are beneficial to enhance the phase stability and corrosion resistance of the zirconate ceramic due to the different ionic radius and basicity of rare-earth oxides (RE 2 O 3 ). More Gd 3+ in SGYSZ can promote the forming and coarsening of the GdVO 4 during mineralization, which can also decrease the loss of Y 3+ from the SGYSZ. The corrosion mechanism is discussed in detail.
研究领域:
材料科学
·
陶瓷
·
高温腐蚀
·
无机化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Yajing Wang,Yane Zheng,Yuhao Wang,Kongzhai Li,Yaming Wang,Lihong Jiang,Xing Zhu,Yonggang Wei,Hua Wang
Chemical-looping reforming of methane (CLRM) offers an effective approach for the production of syngas . A series of Ce x Zr y Cu 1−x−y (x = 0.6, 0.7, y = 0–0.35) mixed oxides were successfully prepared by sol-gel method, and characterized by means of XRD , H 2 -TPR, BET, XPS , Raman and CH 4 -TPR. The addition of Cu and Zr ions caused the distortion of CeO 2 lattice and induced more oxygen vacancies , which promoted the mobility of lattice oxygen in the materials. Ce x Zr y Cu 1−x−y mixed oxides also owned smaller grain size and better thermal stability than pure CeO 2 -CuO mixed oxides. Among the series of Ce x Zr y Cu 1−x−y mixed oxides, the reducibility of Ce 0.6 Zr x Cu 0.4−x and Ce 0.7 Zr x Cu 0.3−x samples gradually increased with the Cu content. It was found that the Ce 0.7 Zr 0.2 Cu 0.1 sample owned the most abundant oxygen vacancies on the surface. The Ce x Zr y Cu 1−x−y mixed oxides with lower Cu content (≤0.1) produced higher amount of H 2 and CO while smaller CO 2 . Ce 0.7 Zr 0.2 Cu 0.1 sample still retained better structural stability and thermal stability after 20 times cycled reaction.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2017
·
IF 4.636
Yuhai Sun,Limin Chen,Yunfeng Bao,Guannan Wang,Yujun Zhang,Mingli Fu,Junliang Wu,Daiqi Ye
Cu-ZrO 2 catalysts supported on nitrogen-doped CNTs were tested for CO 2 hydrogenation to methanol in a fixed-bed plug flow reactor. The characterization results indicate that the presence of pyridinic nitrogen increases the copper oxide dispersion, promotes their reduction, decreases the Cu particle size and enhances H 2 adsorption capability; the activated CO 2 adsorption predominantly controls CO 2 conversion. In addition, pyridinic nitrogen contributes to the strong adsorption of CO 2 , stimulating methanol formation, while pyrrolic nitrogen contributes to the medium adsorption of CO 2 , mainly boosting CO formation. Thus, pyridinic nitrogen dominant CNTs supported catalyst (CZ/CNT-N) possesses more active sites compared with the other three catalysts, leading to maximum methanol yield (8.64%) and space time yield (102.21 mg g −1 cat h −1 ); pyrrolic nitrogen dominant CNTs supported catalyst (CZ/CNT-NH 2 ) obtains more highly active structure, giving the highest intrinsic activity (TOF values).
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 7
·3727-3735
·
IF 3.108
Dandan Li,Yuchen Xie,Huaisong Yong,Dazhi Sun
We report the synthesis and tribological characterization of zirconia (ZrO2) nanoparticles in base mineral oil and commercial formulated lubricating oils. A modified chemical method was applied to prepare nano-sized ZrO2 structurally stabilized with yttria (Y2O3) in a precipitation process with the addition of various surfactants (polyethylene glycol, polyvinyl pyrrolidone, and polyether amine). Characterizations by X-ray diffraction and transmission electron microscopy show that polyether amine facilities the formation of stable ZrO2 with coexisting tetragonal and monoclinic phases and is better in preparing Y2O3-stabilized ZrO2 nanoparticles with a smaller particle size and narrower size distribution compared to the other surfactants used. The friction and anti-wear characteristics, which were tested with a four-ball module, indicate that the as-prepared Y2O3-stabilized ZrO2 nanoparticles perform better in commercial formulated lubricating oils than in the base mineral oil medium, and 0.1–0.5 wt% nanoparticles should be sufficient to achieve good tribological performance in lubricating oils.
研究领域:
材料科学
·
摩擦学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2020
·
IF 12.35
Zihao Zhang,Meizan Jing,Hao Chen,Francis Okejiri,Jixing Liu,Yan Leng,Haolan Liu,Weiyu Song,Zhaoyin Hou,Xiuyang Lu,Jie Fu,Jian Liu
The catalytic transformation of renewable fatty acids into value-added fatty alcohols without the use of gaseous hydrogen is a versatile technique for the utilization of microalgae and waste cooking oil, where Cu-based catalysts are considered to be the most suitable candidate. However, the interpretation of the structure–reactivity relationship caused by different crystal types of carriers and the metal–support interface is not well understood. Herein we synthesized ZrO2-supported Cu nanoparticle catalysts via different preparation methods and reduction temperatures under similarly exposed surface facets and Cu valency but different polymorphic phases of ZrO2 (monoclinic ZrO2: m-ZrO2; tetragonal ZrO2: t-ZrO2) and the metal–support interface. Interestingly, the as-synthesized Cu/t-ZrO2 catalysts showed remarkably better catalytic performance than Cu/m-ZrO2 for the in situ hydrogenation of lauric acid in the methanol–water system. Combined experimental and density functional theory (DFT) calculation results ascribed the lower efficiency of m-ZrO2 as a carrier to weakly adsorbed reactant and intermediate molecules as well as the absence of an oxygen vacancy in the crystal phase. The interface-rich Cu/t-ZrO2 catalysts displayed higher activity normalized to the surface-exposed Cu sites toward lauryl alcohol production than the interface-deficient counterparts. DFT calculation results further revealed that this metal–support interface plays an important role in promoting the C–O bond or H–H bond cleavage in two possible reaction routes, thus reducing the activation barrier of the overall reaction.
研究领域:
催化化学
·
可再生能源
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Le Fu,Bohan Wang,Wei Xia
We have previously observed that doping of Ca ions was beneficial to the formation of zircon (ZrSiO 4 ). It is well known that synthetic ZrSiO 4 is typically formed via a solid-state reaction between ZrO 2 and SiO 2 , in which the interfaces between the reactant and resultant play an important role. However, the interfaces are lacking detailed microstructural observation. This follow-up study aims at exploring the formation mechanism of ZrSiO 4 by inspecting the interfaces at the nano and atomic scales with TEM techniques. Results demonstrated that ZrSiO 4 was formed in the Ca-doped sample after sintering at 1200 °C, whereas, no ZrSiO 4 was formed in the undoped sample even after sintering at 1230 °C. The Ca-doped sample consisted of a continuous ZrSiO 4 matrix with dispersed ZrO 2 nanocrystallites . Doping of Ca ions promoted the formation of ZrSiO 4 by causing lattice distortion and oxygen vacancies in ZrO 2 lattices. Thin amorphous grain boundary complexions were found between ZrO 2 nanocrystallites and between ZrO 2 and ZrSiO 4 crystallites . These amorphous complexions acted as reaction sites and an intermediate metastable state for the solid-state reaction. A detailed formation mechanism of ZrSiO 4 at the nanometer scale and atomic scale has been proposed.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2023
·
IF 4.1
Yan Huo,Renzhe Li,Shijian Xiu,Yating Wang,Lianji Zhang,Aihua Jin,Bo Quan
Gold (Au) and zirconia (ZrO 2 ) nanoparticles as the co–catalyst on modified multi–walled carbon nanotubes (Au/ZrO 2 @MWCNTs) were prepared by simple method. ZrO 2 and Au NPs, Au/ZrO 2 @MWCNTs exhibited excellent electrochemical performances when applied as glucose sensor . The sensor showed a wide linear operating range (10 μM to 13 mM glucose concentration), high sensitivity (162.52 μA cm −2 mM −1 at 10 μM–13 mM), and a low detection limit (0.95 μM) at 0.2 V. After 15 days of consecutive tests, over 90.0 % of the original current was retained, verifying the stability of Au/ZrO 2 @MWCNTs. Furthermore, the non–enzymatic glucose sensor also exhibited strong catalytic activity for the conversion of glucose to gluconic acid with a large active surface area. It is expected to be applicable in the further development of non–enzymatic glucose sensors.
研究领域:
材料科学
·
电化学
·
生物传感
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2023
·Vol. 25
·期 21
·8531-8538
·
IF 9.8
Rong Fu,Yan Wang,Guangming Wang,Qingyun Zhan,Lili Zhang,Le Liu
Well-crafted semiconductors exhibiting favorable band structures and strong electron-donating properties can provide a viable pathway for solar-driven nitrogen activation under ambient conditions. In this study, we demonstrate that the nitrogen photo-fixation process can be enhanced by introducing oxygen vacancies and a Ru co-catalyst. The Ru-loaded ZrO2−x photocatalyst achieved an impressive NH3 production rate of 3256 μg g−1 h−1 under visible light irradiation (at 400 nm). Defective ZrO2−x with its enhanced reducing ability and narrow band gap possesses a low work function and excellent electron-donating capability, resulting in remarkable photocatalytic performance for ammonia synthesis under visible light. The supported Ru co-catalyst induces upward band bending in defective ZrO2−x, forming an interfacial Schottky barrier that facilitates the separation of photogenerated charge carriers and provides energetic electrons for nitrogen activation. Mott–Schottky photocatalysts with enhanced back donation ability establish a one-way channel for the transmission of photoexcited electrons, thereby further improving the photocatalytic performance of ammonia synthesis at room temperature.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2023
·
IF 4.3
Liu Qing-Qing,Lin Qiu-Hao,Qi Xiao-Dong,Zhang Nan,Huang Ting,Yang Jing-Hui,Wang Yong
Polymer dielectrics with a high energy density and an available energy storage capacity have been playing an important role in advanced electronics and power systems. Nevertheless, the use of polymer dielectrics in harsh environments is limited by their low energy density at high temperatures. Herein, zirconium dioxide (ZrO 2 ) nanoparticles were decorated with amino group utilizing 4,4-methylenebis (phenyl isocyanate) (AMEO) and successfully incorporated into polyetherimide (PEI) matrix. The dielectric properties, breakdown strength, and energy storage performances of PEI/ZrO 2 -AMEO nanocomposites were investigated from 25 °C to 150 °C. It is found that the combination of moderate bandgap ZrO 2 with modest dielectric constant and polar groups at interface with deep trap can offer an available strategy to simultaneously increase the dielectric constant and breakdown strength of polymer dielectrics. As a result, the composites containing ZrO 2 -AMEO exhibit excellent energy storage performance at elevated temperatures. Specially, the PEI-based composites with 3 vol% ZrO 2 -AMEO display a maximum discharged energy density ( U d ) of 3.1 J/cm 3 at 150 °C, presenting 90% higher than that of neat PEI. This study may help to better develop the polymer-based dielectric composite applied at elevated temperatures.
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
Lizheng Zhang,Yong Zeng,Haihua Yao,Zhaoyao Shi,Jimin Chen
To date, overcoming the trade-off between high solid loading and print accuracy and strength , achieving high-performance and fine ZrO 2 micro-ceramic components through vat photopolymerization 3D printing remains challenging. In this study, the effects of dispersant, particle size and solid content on the dispersion, rheological behavior and stability of ZrO 2 ceramic slurry were systematically studied, and complex, fine and high-performance ZrO 2 micro-ceramic gears were successfully prepared. Then, the microstructure, mechanical properties, tribological properties and surface quality were evaluated. The results show that the rheological behavior of the slurry is the best when the optimal dispersant content is 3.5 wt%. With the increase of solid content, the sintering shrinkage of ZrO 2 (3Y)/Al 2 O 3 ceramics decreased, while the relative density, compressive strength , flexural strength , fracture toughness and hardness increased. The prepared micro-ceramic gears not only have fine structure, but also have dense microstructure and good mechanical properties. The relative density, compressive strength, flexural strength, fracture toughness and hardness strength of ZrO 2 (3Y)/Al 2 O 3 ceramics can reach 98.53 %, 1900 MPa, 648 MPa, 6.4 MPa × m 1/2 and 13.40 GPa, respectively. In particular, this study couples the printing accuracy and strength with the solid load. By adjusting the relationship between the fixed load and the shrinkage rate, the printing of samples with different sizes is realized, which breaks through the accuracy limit of the printing equipment and provides a new idea for the preparation of micro-ceramic gears.
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Xiaoxu Zhang,Dongbin Zhu,Jinsheng Liang,Shuang Zeng
Aiming to obtain 3D-printed ZrO 2 ceramics with high strength-toughness, this work developed zirconia/tourmaline ceramic inks suitable for material extrusion, and proposed a novel strategy of in-situ formation whiskers to improve the interlayer bonding and intralayer microstructure of 3D printed ZrO 2 ceramics. Effect of tourmaline contents on the ceramic inks printability, the mechanical properties and microstructure formation of in-situ whiskers reinforced zirconia ceramics were systematically investigated. When the addition of tourmaline was 4 vol%, printed different 3D structures presented a good retention, owing to the zirconia/tourmaline ceramic inks with good rheological behavior. Compared to the pure zirconia ceramics, incorporated tourmaline particle significantly increased the relative density of 3D-printed zirconia ceramics from 97.52 % to 98.92 %, the optimal flexural strength of 612 ± 32 MPa and fracture toughness of 5.98 ± 0.20 MPa m 0.5 were obtained for 3D-printed zirconia composite ceramics. The strengthening mechanism is attributed to the higher densification of zirconia ceramics and the in-situ formation mullite whiskers in interlayer and intralayer microstructure, which is demonstrated via systematical characterizations. This interlayer strengthening method based on in-situ formation whisker provides an effective and convenient approach to fabricating 3D-printed zirconia ceramics with high strength and toughness.
✓ 已验证
产品关联
DOI
高影响因子
CORROSION SCIENCE
·
2019
·
IF 6.355
Yunxing Pan,Shengli Cheng,Hang Dong,Nan Li,Feng Bao,Jinyan Wang,Xigao Jian
A novel oxidation resistant thermoset polymer (MSCB) with excellent thermo-oxidative stability and good solubility was designed and synthesized. To prevent C/C composites from oxidation, a series of MSCB polymer-based coatings were prepared by precursor infiltration and thermal-curing at 300 ℃. The oxidation behaviour of the MSCB-, MSCB/TiO 2 -, MSCB/ZrO 2 - and MSCB/SiC-coated C/C composites was studied. The improved oxidation resistance of the C/C composites was attributed to the good adhesion of the coatings and the formation of a borosilicate protective layer on the surface of the coatings, which was confirmed by the results of TGA, SEM, XPS, and XRD analyses.
研究领域:
材料科学
·
聚合物化学
·
复合材料
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）