CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Daming Yang,Guiru Sun,Xinru Wang,Fengyang Li,Ze Gao,Pingli Zhang,Wei Lu,Ming Feng
The photo-assisted lithium-oxygen (Li-O 2 ) cell is widely concerned due to its low overpotential. However, rapid recombination rate of photogenerated electrons and holes remains a fundamental challenge for photo-assisted Li-O 2 cells. Herein, we design an optical and magnetic fields co-assisted Li-O 2 cell based on α-Fe 2 O 3 nanospindles. We employed PL spectrum and I-t curve confirm that under the magnetic field, the photogenerated electrons and holes are driven via the opposite Lorentz forces in photo-assisted Li-O 2 cells, which is beneficial to accelerating the formation and decomposition of Li 2 O 2 . The optical and magnetic fields co-assisted Li-O 2 cell based on α-Fe 2 O 3 nanospindles achieves an ultra-high discharge platform of 3.47 V and a low charge platform of 3.57 V, as well as a surprising energy efficiency of 97.2%. In addition, the optical and magnetic fields co-assisted Li-O 2 cell can stably cycle for over 25 cycles. This study offers a reference for improving the electrochemical kinetics of photo-assisted Li-O 2 cell by introducing magnetic field, which opens up a new avenue for the development of high-performance Li-O 2 cells.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Materials Interfaces
·
2020
·Vol. 8
·期 5
·2001831
·
IF 4.948
Peng Wang,Su-Zhen Wang,Qing Han,Dong-Qinq Zou,Wen-Kai Zhao,Xue-Dong Wang,Chen Luo,Xin Yang,Xing Wu,Wan-Feng Xie
Gas sensors based on SnO 2 , Fe 2 O 3 , and their nanocomposites are promising candidates for sensing of acetone, ethanol, hydrogen, NO 2 , ozone, and formaldehyde. In this work, a rational hydrothermal route is designed to prepare α-Fe 2 O 3 /SnO 2 porous sphere arrays assembled with hierarchical nanostructure (denoted as α-Fe 2 O 3 ( x %)/SnO 2 ). The results demonstrate that the α-Fe 2 O 3 (4%)/SnO 2 based sensor exhibits excellent sensing performance, the short response/recovery time of 3 and 4 s, respectively. A very low working temperature of 200 °C, wide linear detection range (from 500 ppb to 500 ppm), and long-term cycling stability of as long as 90 days, and stable performance at 80% of relative humidity. The sensing signals can be accurately sampled and processed by the integrated circuit system, to collect and monitor the acetone concentration alteration signals in real time. Furthermore, the gas sensing performance is interpreted by the functions of hierarchical nanostructure and synergistic effect of Fe 2 O 3 /SnO 2 nanohybrids.
研究领域:
材料科学
·
传感器技术
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2020
·Vol. 31
·期 9
·6779-6785
·
IF 2.22
Wu Bao-Shui,Wang Peng,Song Jian
A mixed-solvothermal method was used to synthesize the α-Fe 2 O 3 nanoparticles with nearly spherical, rod-like, disk-like morphologies by varying the precipitant or solvent. When used as the anode material for Li-ion batteries, the nearly spherical α-Fe 2 O 3 nanoparticles with a high monodispersity and an average diameter of about 50.5 nm exhibited much better cycle stability and rate performance than their disk-like and rod-like equivalents. Their reversible capacity reached up to 1500 mAh/g that far exceeded their theoretical value (1007 mAh/g) at a current density of 0.1 A/g. Even after 100 cycles, there was still a capability retention of about 1200 mAh/g. Moreover, the analysis of the Nyquist plots revealed that the nearly spherical α-Fe 2 O 3 nanoparticles presented the lowest charge-transfer resistance among the three samples. The present study provides an effective way to control the morphologies of nanoparticles, and these nanostructures would present great potentials for the applications in LIBs or some other fields.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Wenjun Zhu,Yuanyu Wang,Yongzhi Yu,Yuehui Hu,Yichuan Chen
In this paper, core-shell structured α-Fe 2 O 3 @Li 4 Ti 5 O 12 composite has been reported based on the design of structure and heterogeneous composite. Compared with pure α-Fe 2 O 3 and α-Fe 2 O 3 @TiO 2 composite, the core-shell structured α-Fe 2 O 3 @Li 4 Ti 5 O 12 composite can deliver a favorable reversible capacity of 898 mAh g −1 at 0.2 A g −1 (642 mAh g −1 at 2 A g −1 ) after 200 cycles and the reversible capacity still maintain 482 mAh g −1 at 3.2 A g −1 . The improved electrochemical property of the composite is attributed to its heterogeneous composite and unique structural advantages: high specific capacity and outstanding rate capability can be guaranteed by the synergistic effect between the inner core of α-Fe 2 O 3 and outer shell of spinel Li 4 Ti 5 O 12 , the large volume variation of α-Fe 2 O 3 can be effectively relieved by spinel Li 4 Ti 5 O 12 with unexceptionable structure stability, and the extra lithium ions storage as well as enhanced kinetics can be contributed by abundant grain boundaries and heterogeneous phase interfaces .
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Ling Cheng,Yulu Tian,Jingdong Zhang
A p-n heterojunction film of Cu 2 O/α-Fe 2 O 3 was constructed by electrodepositing p-type Cu 2 O microcubes on liquid phase deposited film of n-type α-Fe 2 O 3 . The surface morphology , the crystal phase and composition of Cu 2 O/α-Fe 2 O 3 heterojunction film were characterized by scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The enhanced absorption in the visible light region was observed in UV–visible diffuse reflectance spectra. Meanwhile, an efficiently improved separation and faster transfer of photogenerated electrons and holes were revealed by photoluminescence spectra and electrochemical impedance spectra. The Cu 2 O/α-Fe 2 O 3 p-n heterojunction was applied to photoelectrocatalytic degradation of oxytetracycline at a bias potential of +0.5 V under visible light illumination. After 60-min photoelectrocatalytic treatment, 73.3% of oxytetracycline was removed and the degradation rate constant reached 2.14 × 10 −2 min −1 . Moreover, the crystal phases and compositions for the used and fresh Cu 2 O/α-Fe 2 O 3 films were studied, and a possible photoelectrocatalytic mechanism was proposed.
研究领域:
材料科学
·
环境科学
·
光催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 13
·7862-7878
·
IF 4.22
Cao Xue-Fang,Yue Pan,Wei Qiu-Rui,Dang Yun-Fei,Zhang Si-Qi,Wei Zhi-Xian,Wang Rong-Zhen
In this study, a solar-driven photocatalyst La 0.7 Sr 0.3 MnO 3 /α-Fe 2 O 3 (20%) with p – n heterojunction structure was synthesized and characterized. The magnetic, photocatalytic properties, Fenton-like action and the synergistic effect of the photocatalysis and Fenton-like on methyl orange (MO) degradation of La 0.7 Sr 0.3 MnO 3 /α-Fe 2 O 3 (20%) were also investigated. Results show that p – n heterojunction was formed, and it has considerable photocatalytic properties under ultraviolet light and solar irradiation. More importantly, La 0.7 Sr 0.3 MnO 3 /α-Fe 2 O 3 (20%) also exhibits Fenton-like catalytic performance in the presence of H 2 O 2 and oxalic acid (OA). The main reactive radicals of the La 0.7 Sr 0.3 MnO 3 /α-Fe 2 O 3 –H 2 O 2 –OA–sunlight system are h + , · OH and · O 2 − . The chemical oxygen demand removal rate of MO wastewater in La 0.7 Sr 0.3 MnO 3 /α-Fe 2 O 3 (20%)–H 2 O 2 –oxalic acid–sunlight system reached 72.4%; the value was higher than that of the sum of single photocatalysis (34.5%) and Fenton-like-dark system (27.6%), indicating that there is a synergistic effect between the photocatalysis and Fenton-like on MO degradation. In addition, La 0.7 Sr 0.3 MnO 3 /α-Fe 2 O 3 (20%) displays approximately superparamagnetism and has higher saturated magnetization ( M s ), low coercive force and residual magnetism. So it can be easily recovered by an external magnetic field and can be reused 6 times. It was anticipated that La 0.7 Sr 0.3 MnO 3 /α-Fe 2 O 3 (20%) with p – n heterojunction structure is a stable and reusable solar-light-driven magnetic photocatalyst and has great potential applications for wastewater treatment. Graphical abstract The magnetic La 0.7 Sr 0.3 MnO 3 /α-Fe 2 O 3 (20%) with p – n heterojunction structure was synthesized and characterized by different methods. The magnetic, photocatalytic properties, Fenton-like action and the synergistic effect of the photocatalysis and Fenton-like on methyl orange (MO) degradation of La 0.7 Sr 0.3 MnO 3 /α-Fe 2 O 3 (20%) were also investigated. It is not only a solar-driven photocatalyst with high efficiency, but also shows excellent Fenton-like catalytic effect. And the photocatalysis and Fenton-like system exhibited synergetic catalytic effect on MO degradation by La 0.7 Sr 0.3 MnO 3 /α-Fe 2 O 3 (20%). Furthermore, near superparamagnetic characteristics of the catalyst make it easy to recycle by the external magnetic field and can be reused for 6 times, suggesting that it is a stable multifunctional catalyst.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2025
·
IF 2.6
Kaiwen Wu,Jichao Shi,Daqing Wang,Honghao Ni,Runping Jia,Yufeng Liu,Lin Lin,Dandan Wu,Shufang Chang,Yaqi Wang,Qing Xin
Magnetic iron oxide is a typical narrow-band gap semiconductor photocatalyst, but its inherent magnetic aggregation effect and high electron–hole recombination rate seriously affect its photocatalytic performance. Here, α-Fe2O3/SiO2 composite aerogels were prepared by combustion technology for the first time. The unique structure of α-Fe2O3/SiO2 composite aerogels with amorphous silica coated with nanocrystalline iron oxide was confirmed. The composite aerogels exhibited a high specific surface area (479 m2 g−1 when calcined at 500 °C), so that they have excellent adsorption properties for organic pollutants (MB, RhB and TC) and Cr(VI). The composite aerogels with a Fe : Si molar ratio of 1 : 2 showed the best visible light photocatalytic properties for MB, RhB and TC. Based on the study of the band gap width, photocurrent density, transient photocurrent response, impedance of photocatalysts, and the unique structure of the composite aerogels, the mechanism of photocatalytic enhancement of composite aerogels was proposed. Finally, the mechanism of the preparation of α-Fe2O3/SiO2 composite aerogels by combustion synthesis was analyzed. It is a potential technology for preparing high performance composite aerogel photocatalysts by high efficiency combustion technology.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Jing Deng,Cheng Ye,Anhong Cai,Linyi Huai,Shiqing Zhou,Feilong Dong,Xueyan Li,Xiaoyan Ma
As a typical iron-based oxide semiconductor with abundant reserves, α-Fe 2 O 3 has been widely used in the domain of photocatalysis and environmental remediation. Here, sulfur doped α-Fe 2 O 3 (S-α-Fe 2 O 3 ) has been successfully fabricated through coprecipitation, hydrothermal and calcination processes and applied to activate persulfate (PS) for carbamazepine (CBZ) degradation under UV irradiation. Systematic characterizations were conducted to analyze the morphology, structure and chemical composite of S-α-Fe 2 O 3 . UV/PS/S-α-Fe 2 O 3 process showed remarkably enhanced photocatalytic performance for CBZ degradation. The degradation rate constant (7.78 × 10 −2 min −1 ) was about 2.2 and 14.1 times as high as that of UV/PS/α-Fe 2 O 3 (3.60 × 10 −2 min −1 ) and UV/PS (5.53 × 10 −3 min −1 ) processes, respectively. With increasing PS concentration and photocatalyst dosage, the removal efficiency of CBZ both increased. UV/PS/S-α-Fe 2 O 3 process can efficiently and steadily operate in a wide pH range of 3.0–8.0. The introduction of water matrix species (i.e. chloride, bicarbonate, nitrate and humic acid) exerted different effects on CBZ degradation. S-dopant was doped via forming ≡Fe III -SO 4 2- bond on S-α-Fe 2 O 3 surface, and doped sulfur functioned as surface electrons trapping centers derived from DFT study. The band gap value of S-α-Fe 2 O 3 was reduced and the separation efficiency of photogenerated electrons and holes was improved. Hydroxyl radicals, sulfate radicals, superoxide radicals and holes all contributed to CBZ destruction. Furthermore, two major routes of CBZ degradation were proposed as hydroxylation and deamination, then followed by decarbonxylation, ketonization and ring cleavage based on the results of HPLC-MS and DFT calculation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Yan-Fei Mu,Chao Zhang,Meng-Ran Zhang,Wen Zhang,Min Zhang,Tong-Bu Lu
Up to now, the majority of the developed photocatalytic CO2 reduction systems need to use expensive sacrificial reductants as electron source. It is still a huge challenge to drive the photocatalytic CO2 reduction using water as an electron source. Herein, we report a facile strategy for the construction of direct Z-scheme heterojunction of LF-FAPbBr3/α-Fe2O3, which is manufactured by the in situ and two-step controlled growth of ligand-free formamidinium lead bromide (LF-FAPbBr3) nanocrystals on the surface of α-Fe2O3 nanorods. The matchable energy levels and direct contact between LF-FAPbBr3 and α-Fe2O3 significantly accelerate the interfacial charge transfer, with a charge separation efficiency (ηseparation) of 93%, much higher than that of 11% shown by the ligand-capped FAPbBr3/α-Fe2O3 heterojunction. The resulting efficient separation and raised redox ability of photogenerated carriers endow the LF-FAPbBr3/α-Fe2O3 heterojunction with an outstanding photocatalytic performance for CO2 reduction (to CO and CH4) coupled with water oxidation (to O2), achieving a highest electron consumption rate of 175.0 μmol g–1 h–1 among the reported metal halide perovskite-based photocatalysts, which are 5 and 11 times higher in comparison with those of sole LF-FAPbBr3 and ligand-capped FAPbBr3/α-Fe2O3, respectively.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2019
·
IF 14.229
Sheng Guo,Haojie Wang,Wei Yang,Hussain Fida,Liming You,Kun Zhou
In this work, a cost-effective and eco-friendly calcium-doped α-Fe 2 O 3 (Ca-Fe 2 O 3 ) with abundant oxygen vacancies was fabricated using a scalable precipitation-calcination method to activate peroxymonosulfate (PMS) for wastewater purification. Density functional theory calculations revealed that the incorporation of Ca 2+ into the α-Fe 2 O 3 structure enhances the electron transfer from α-Fe 2 O 3 to PMS, facilitating the activation of PMS. The degradation of Rhodamine B by 5%Ca-Fe 2 O 3 proceeded with a reaction constant 8 times higher than that of pristine α-Fe 2 O 3 . This can be attributed to the increased generation of 1 O 2 and O 2 • − , increased specific surface area and enhanced electrical conductivity. The applicability of the 5%Ca-Fe 2 O 3 /PMS system was investigated including its operating parameters and stability, and the intermediates involved in the reaction were identified. The 5%Ca-Fe 2 O 3 /PMS system exhibited excellent degradation efficiency in natural water samples. This work opens up new perspectives for designing highly efficient catalysts and renders iron oxides potential candidates for environmental remediation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2016
·
IF 5.393
Ting Liu,Lucheng Xue,Xin Guo,Jia Liu,Yu Huang,Chuguang Zheng
The reaction mechanisms of a mixture gas of HCl, O2, and SO2 in Hg0 adsorption on α-Fe2O3(001) surface are clarified by a group of adsorption experiments and theoretical calculations based on the density functional theory. The role of O2 in removing Hg0 is greatly influenced by the reaction temperature, meanwhile, the O atom coverage could affect the adsorption performance of Hg0. The dissociated O2 competes with the active sites of Cl species on Fe surface at low temperature, however, at medium temperature HCl and O2 could simultaneously facilitate the Hg0 transformation. Combined with the theoretical calculations, the role of SO2 and the probable pathways in removing Hg0 are discussed. Lower concentration of SO2 as well as HCl could dissociate on α-Fe2O3(001) surface, and the intermediates combine with gaseous Hg0, forming mercury–sulfur, mercury–chlorine compounds, and so forth. In addition, the different concentrations of SO2 are also discussed, and the corresponding X-ray photoelectron spectroscopy analysis on contrasted samples is conducted to research the morphological characterization, providing a reliable basis for judging the probable pathways of Hg0 transformation.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysts
·
2022
·Vol. 12
·期 6
·645
·
IF 4.501
Lian Sun,Qian Zhang,Qijie Liang,Wenbo Li,Xiangguo Li,Shenghua Liu,Jing Shuai
The counter electrode (CE) is an important and vital part of dye-sensitized solar cells (DSSCs). Pt CEs show high-performance in DSSCs using iodide-based electrolytes. However, the high cost of Pt CEs restricts their large-scale application in DSSCs and the development of Pt-free CE is expected. Here, α-Fe2O3/reduced graphene oxide (α-Fe2O3/RGO) composites are prepared as the Pt-free CE materials for DSSCs. A simple hydrothermal technique was used to disseminate the α-Fe2O3solid nanoparticles uniformly throughout the RGO surface. The presence of the α-Fe2O3nanoparticles increases the specific surface area of RGO and allows the composites to be porous, which improves the diffusion of liquid electrolyte into the CE material. Then, the electrocatalytic properties of CEs with α-Fe2O3/RGO, α-Fe2O3, RGO, and Pt materials are compared. The α-Fe2O3/RGO CE has a similar electrocatalytic performance to Pt CE, which is superior to those of the pure α-Fe2O3and RGO CEs. After being fabricated as DSSCs, the current–voltage measurements reveal that the DSSC based on α-Fe2O3/RGO CE has a power conversion efficiency (PCE) of 6.12%, which is 88% that of Pt CE and much higher than that of pure α-Fe2O3and pure RGO CEs. All the results show that this work describes a promising material for cost-effective, Pt-free CEs for DSSCs.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
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