MATERIALS LETTERS
·
2019
·
IF 3.019
Dayan Xie,Kuibao Zhang,Weiwei Li,Baozhu Luo,Haibin Zhang
Lanthanum chromite (LaCrO 3 ) is a promising functional material because of its high melting point, high thermal conductivity and excellent fire resistance. In this study, LaCrO 3 was successfully prepared by self-propagating high-temperature synthesis (SHS) method using CrO 3 and Cr as the oxidant and reductant. The optimum mole ratio of La 2 O 3 , Cr and CrO 3 was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The result shows that the LaCrO 3 powder with acceptable purity and good morphology was obtained when Cr and CrO 3 are 10% excess over La 2 O 3 . The real temperature of SHS system reaction was recorded by paperless recorder. The particle size distribution of the SHS prepared LaCrO 3 powder demonstrates median diameter of 1040 nm according to laser particle size spectrometer.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
TRIBOLOGY INTERNATIONAL
·
2022
·
IF 5.62
Shuna Chen,Yunfeng Su,Qiuan Sun,Hengzhong Fan,Junjie Song,Litian Hu,Yongsheng Zhang
A fibrous monolithic ceramic was constructed with Al 2 O 3 fiber cells surrounded by Cr 2 O 3 phase-two kinds of brittle ceramics, to achieve an excellent combination of high strength and toughness, which is usually mutually exclusive in engineering materials . The material was demonstrated to fail in a non-brittle fracture manner and showed a typical rising R-curve behavior with the maximum crack growth toughness of 9.05 MPa m 1/2 . Meanwhile, the composite ceramic exhibited excellent tribological performance at high temperatures, with the lowest friction coefficient of 0.29 and wear rate of 1.07 × 10 −5 mm 3 /Nm at 600 °C. It was also demonstrated that the thermal stability of Cr 2 O 3 has a great influence on the wear mechanism when the temperature was above 800 °C.
研究领域:
材料科学
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工程学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2016
·Vol. 51
·期 24
·11002-11013
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IF 2.302
Han Wenfeng,Wang Zhikun,Li Xiaojuan,Tang Haodong,Xi Miao,Li Ying,Liu Huazhang
Nano-Cr 2 O 3 was prepared via solution combustion synthesis (SCS) with Cr(NO 3 ) 3 ·9H 2 O as the Cr precursor and glycine as the fuel. The effect of molar ratio of glycine to Cr in the feed during solution combustion was investigated. Cr 2 O 3 samples were characterized by XRD, SEM, TEM, H 2 -TPR, and XPS. In addition, these catalysts were evaluated for the dehydrofluorination of 1,1-difluoroethane producing vinyl fluoride (VF, CH 2 =CHF). The results confirm that Cr 2 O 3 is in relatively uniform flakes or flat particles via solution combustion synthesis with the particle size of 50–200 nm and composed by the aggregation of 58–77 nm nanoparticles. The specific surface area of higher than 30 m 2 g −1 is achieved, which is comparable to the values obtained by solvothermal route. For the dehydrofluorination of 1,1-difluoroethane, high conversion levels (83 % for commercial catalyst and 93 % for SCS catalyst) are achieved at 350 °C, and the activity of SCS catalyst is at least 2× higher than that of commercial Cr 2 O 3 at reaction temperatures below 300 °C. Compared with commercial Cr 2 O 3 , XPS, and H 2 -TPR reveal the higher CrO 3 contents on the surface of Cr 2 O 3 derived from SCS. It is suggested that CrO 3 plays a major role in the catalytic performance as high-valent Cr species such as Cr(VI) are vital for the reaction because they could be transformed to the active species such as CrO
x
F
y
. In addition to the high activity, compared with commercial Cr 2 O 3 , SCS catalyst also show higher stability. Following the reaction of 120 h at 300 °C, no noticeable deactivation is observed while the activity of commercial Cr 2 O 3 declines with TOS. High surface area and much smaller size of Cr 2 O 3 crystalline favors the formation of CrO
x
F
y
during reaction over Cr 2 O 3 -3.33 catalyst probably contribute to the high activity and stability.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2025
·
IF 2.6
Guixin Zhao,Jinzhao Huang,Feng Jiao,Ke Zhang,Yu Zhang,Jiabei Xue,Xiaolong Deng
NiCoFe-based multicomponent alloy catalysts have been extensively studied as non-precious metal high-entropy alloy catalysts. They exhibit outstanding electrochemical performance in the electrolytic hydrogen production process. Here, we employ one-dimensional carbon nanotubes as a substrate to prepare a series of carbon-based high-entropy heterostructure catalysts. The NiCoFeMnLa/CNTs@Cr2O3 composite structure is obtained by forming oxides on the surface via vapour deposition, effectively increasing the number of active sites. The carbon-based transition metal nanomaterial catalyst NiCoFeMnLa/CNTs@Cr2O3 exhibited outstanding performance in the alkaline electrolytic catalysis of the oxygen evolution reaction, achieving an overpotential of merely 235 mV at a current density of 10 mA cm-2 in alkaline simulated seawater solution. Notably, the catalyst maintained relatively stable current density during 24 h electrochemical testing, indicating that the NiCoFe multicomponent alloy catalyst combined with Cr2O3 combination holds promise for enhanced stability during seawater electrolysis. Driven by these findings, this work may offer novel insights into the rational design of highly efficient electrocatalysts for green hydrogen production processes, particularly concerning carbon-based high-entropy alloy nanoparticle catalysts.
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2018
·
IF 2.873
Wenjie Lin,Weiliang Wu,Jie Bao,Zongtao Liu,Kaifu Qiu,Lun Cai,Zhirong Yao,Youjun Deng,Zongcun Liang,Hui Shen
The dopant-free back contact solar cells are demonstrated based on hole selective contact material, chromium trioxide (CrO x , x < 3) with a low melting point for high stability and high performance. In this contribution, CrO x is first applied in silicon based solar cell as the emitter. Integrating 5 nm CrO x and 2 nm LiF x into solar cell as the emitter and the back surface filed, resulted in a device efficiency of 13.6%. For further improvement, the back contact solar cell reaching an efficiency of 15.8% was fabricated, by implementing the multilayer films of CrO x (5 nm)/Au (4 nm)/ CrO x (5 nm) as the emitter. The formation of Cr(OH) 3 in ambient condition, resulted in a lower work function (4.8 eV) of the CrO x film. Furthermore, the multilayer back contact solar cell demonstrated a high stability due to CrO x covered with 500 nm Ag, when stored in ambient air longer than 170 days.
研究领域:
材料科学
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光伏技术
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半导体器件
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表面工程
·
能源材料
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2025
·
IF 14.9
Chaojie Cheng,Bicen Yao,Siyu Wu,Wankun Gou,Xiaoai Luo,Xiang Chen,Xianrong Zhang,Hongming Sun,Cheng-Peng Li,Baoguang Mao
Efficient alkaline hydrogen evolution reaction (HER) catalysts are critical for anion exchange membrane water electrolysis (AEMWE). However, the intrinsic scaling relationship between water dissociation and OH desorption fundamentally impedes designing catalysts requiring concurrent superior water dissociation and facile OH desorption. Here, we engineer a superhydrophilic Ru/Cr 2 O 3 heterostructured electrocatalyst through in situ confinement of Ru nanoparticles (5–10 nm) within a Cr 2 O 3 matrix. Acting as a Lewis acid, the Cr 2 O 3 component provides alternative sites for water dissociation, accelerating the Volmer step kinetics and downshifting the Ru d -band center via interfacial charge transfer, while simultaneously adsorbing OH − to form a surface-bound Lewis base that repels excess OH − from Ru sites, thereby suppressing hydroxyl over-adsorption. Concurrently, the superhydrophilic surface architecture promotes efficient hydrogen bubble release, thereby reducing mass transport resistance. As a result, the Ru/Cr 2 O 3 heterostructured electrocatalyst exhibits an ultralow overpotential of 36.7 mV at 10 mA cm −2 and a Tafel slope of 33.2 mV dec −1 . Integrated into an AEMWE device, the electrode delivers 500 mA cm −2 for 2000 h in 1.0 M KOH, underscoring its industrial viability (hydrogen production energy consumption per cubic meter (EW): 3.94 kW h m −3 ; electricity-to-hydrogen energy conversion efficiency (η ETH ): 89%@80 °C).
研究领域:
电催化
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材料科学
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能源化学
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界面化学
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氢能技术
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2019
·Vol. 24
·期 2
·361
·
IF 3.06
Haili Wang,Wenfeng Han,Xiliang Li,Bing Liu,Haodong Tang,Ying Li
Cr2O3nanoparticles were prepared by solution combustion synthesis (SCS) with chromium nitrate as the precursor and glycine as the fuel. Commercial Cr2O3and Cr2O3prepared by a precipitation method were also included for comparison. The morphology, structure, acidity and particle size of fresh and spent Cr2O3catalysts were investigated by techniques such as XRD, SEM, TEM, BET and NH3-TPD. In addition, catalytic performance was evaluated for the dehydrofluorination of 1,1,1,3,3-pentafluoropropane (CF3CH2CHF2, HFC-245fa) to 1,3,3,3-tetra-fluoropropene (CF3CH=CHF, HFO-1234ze). The catalytic reaction rate of Cr2O3prepared by SCS method is as high as 6 mmol/h/g, which is about 1.5 times and 2 times higher than that of precipitated Cr2O3and commercial Cr2O3, respectively. The selectivity to HFO-1234ze for all the catalysts maintains at about 80%. Compared with commercial and precipitated Cr2O3, Cr2O3-SCS prepared by SCS possesses higher specific surface area and acid amount. Furthermore, significant change in the crystal size of Cr2O3prepared by SCS after reaction was not detected, indicating high resistance to sintering.
研究领域:
材料化学
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催化化学
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纳米材料科学
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环境友好化工
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氟化学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2025
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IF 7.3
Fuli Wang,Xintong Wei,Shumin Cheng,Denghao Ouyang,Guodong Li,Mirabbos Hojamberdiev,Bin Dong,Han Hu,Yongming Chai
Nickel sulfide (NiSx) catalysts typically suffer from sluggish kinetics and poor stability under ampere-level current densities in the alkaline hydrogen evolution reaction (HER). To address this, we construct Cr2O3-embedded Ni7S6 nanowires on nickel foam (Ni7S6−Cr2O3/NF) with tailored work function differences. Operando analyses and theoretical calculations reveal that interfacial charge redistribution creates a hydrogen-rich microenvironment by accelerating water dissociation at electron-deficient Cr sites and optimizing H* adsorption at electron-rich Ni sites. The catalyst achieves an industrially relevant current density of −1000 mA cm−2 at an overpotential of 369 mV and maintains stability for 1000 h due to the protective Cr2O3 layer. Furthermore, the assembled anion exchange membrane electrolyzer operates at only 1.86 V to deliver 1000 mA cm−2 and remains stable for 500 h. This work highlights interface engineering of local microenvironments as an effective strategy for developing industrial grade electrocatalysts for alkaline HER.
研究领域:
材料科学
·
电化学
·
催化
·
纳米技术
·
能量转换
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）