ACS Catalysis
·
2019
·
IF 12.221
Yan Liu,Xiangdong Kong,Xu Guo,Qiuyao Li,Jingwen Ke,Ruyang Wang,Qunxiang Li,Zhigang Geng,Jie Zeng
Electroreduction of N2 into NH3 represents a promising method for N2 fixation. However, due to the inertness of N≡N covalent triple bonds, this process remains a huge challenge to achieve a high yield rate of NH3. In this work, we designed an effective approach to promoting N2 activation by introducing oxygen vacancies into LaCoO3. In N2 electroreduction, LaCoO3 with oxygen vacancies (denoted as Vo-LaCoO3) exhibited a Faradaic efficiency of 7.6% for NH3 at −0.6 V versus the reversible hydrogen electrode (RHE). Notably, at −0.7 V versus RHE, the yield rate for NH3 of Vo-LaCoO3 reached 182.2 μgNH3 mg–1cat. h–1, which was 2.8 times higher than that (65.3 μgNH3 mg–1 h–1) of pristine LaCoO3. To the best of our knowledge, the yield rate for NH3 of Vo-LaCoO3 approaches the activities of the state-of-the-art catalysts toward N2 electroreduction. Density functional theory calculations revealed that enhanced activation of N2 over Vo-LaCoO3 originated from the increased charge density around the valence band edge via the introduction of oxygen vacancies. Furthermore, the analysis of the thermodynamic limiting potentials for N2 reduction and H2 evolution demonstrated the higher selectivity for N2 electroreduction over Vo-LaCoO3 relative to pristine LaCoO3.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2021
·
IF 8.067
Fan Wang,Weihua Gu,Jiabin Chen,Qianqian Huang,Mingyang Han,Gehuan Wang,Guangbin Ji
Perovskite LaCoO 3 is of great potential in electromagnetic wave absorption considering its outstanding dielectric loss as well as the existing magnetic response with the magnetic doping. However, the dissipation mechanism of the magnetic doping on the microwave absorption is lack of sufficient investigated. In this paper, LaCo 1- x Fe x O 3 ( x =0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, LCFOs) perovskites with different Fe doping amounts were prepared successfully by the sol-gel method and subsequent heat treatment in the air atmosphere. The structure characterization carried out by the first-principles calculations shows the effect of Fe doping on the dielectric and magnetic properties of LCFOs and the strong hybridization of Co/Fe-3d with O-2p in the LCFOs system was successfully demonstrated. Particularly, when x =0.1 and the thickness is only 1.95 mm, the LaCo 0.9 Fe 0.1 O 3 exhibits the best microwave absorption performance with the minimum reflection loss (RL) value of about -41 dB. The typical samples achieve a broad effective absorption bandwidth (EAB) of 5.16 GHz (7.92-13.08 GHz), which covers the total X band (8-12 GHz). Considering that, the especial Fe doping perovskite is promising to be a candidate as efficient microwave absorbers.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2017
·Vol. 44
·期 2
·1013-1024
·
IF 1.369
Li Yan,Hu Yingfei,Fang Tao,Li Zhaosheng,Zou Zhigang
BiVO 4 has emerged as a promising material for solar water splitting. The poor ability of charge transport and separation always limits its performance for photoelectrochemical water splitting. Herein, we coupled n-type BiVO 4 with p-type LaFeO 3 and LaCoO 3 , achieving a photocurrent more than two times as high as bare BiVO 4 at 1.23 V versus a reversible hydrogen electrode. Also, the onset potential was negatively shifted about 260 mV. The promotion of performance is mainly because the space charge layer in BiVO 4 is broadened, and the band bend is enhanced, which facilitates the separation and transport of photo-generated charges.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Na Zhang,Enqi Liu,Hongwei Chen,Jinhui Hou,Chao Li,Hongri Wan
In order to solve the problem of low capacity and volume expansion of LaCoO 3 , LaCoO 3 /Co 3 O 4 perovskite composites were effectively fabricated by a simple hydrothermal method coupled with calcination process. When the calcination temperature is 800 °C, due to the nanoscale sizes, mesoporous structure and heterogeneous components, the samples (named LaCoO 3 /Co 3 O 4 -800) exhibit excellent lithium storage performance as lithium ion batteries (LIBs) anodes. LaCoO 3 /Co 3 O 4 -800 anode exhibits a high reversible capacity (549.7 mAh/g after 100 cycles at 100 mA/g) and superior cycling stability (396.7 mAh/g after 1000 cycles at 1 A/g). This research provides potential candidates for perovskite lanthanide nanomaterials for LIBs anodes.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Wei Zhao,Ruixuan Weng,Huimin Shi,Xueyi Mei,Weiming Nie,Yexin Zhang,Zhaoliang Zhang,Ying Xin,Peng Lu,Jian Zhang,Pu-Xian Gao
In coping with the rapid emission of massive soot particles during the cold starts of diesel vehicles, achieving rapid catalytic soot combustion at low temperatures is a formidable challenge. Herein, we developed an electricity-pulse-sparked catalysis (EPSC) strategy on a conductive LaCoO 3 perovskite catalyst, creating instantaneous soot combustion. As soon as 800 J of electricity pulse is applied, approximately 80 % of soot is combusted within 1 min at <300 °C, exhibiting the higher reaction rates (180−1300 µmol g cat −1 s −1 ) and energy efficiencies (18−100 g soot kWh −1 ) than previously reported results for catalytic soot combustion. Moreover, the EPSC eliminates the gap of contact between soot and catalyst that is a longstanding bottleneck for the specific solid (soot)-solid (catalyst)-gas (O 2 ) reaction, which can be synchronized with the frequently engine start/stop operations, demonstrating potential to address the challenges of soot emissions for hybrid powers.
研究领域:
环境科学
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材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Wen Xie,Guangyan Xu,Yan Zhang,Yunbo Yu,Hong He
A mesoporous LaCoO 3 perovskite oxide (LaCoO 3 -Meso) with three-dimensionally ordered helical interwoven structure was synthesized by a nano-casting method using KIT-6 as the hard template. The obtained LaCoO 3 -Meso with high surface area was tested for its catalytic performance in the NO x storage and reduction (NSR) reaction and compared with a sample synthesized by the conventional sol-gel method. The LaCoO 3 -Meso showed a significant advantage for NO x storage, with a NO x storage capacity 2 times higher than the regular sample. LaCoO 3 -Meso also exhibited improved NSR catalytic performance in the 150–450 °C temperature range, especially within 350–400 °C, where the NO x conversion was raised for 40%. The results of X-ray photoelectron spectroscopy and X-ray absorption fine structure measurements suggested the presence of a high concentration of oxygen defects on the LaCoO 3 -Meso surface. Further results provided by temperature programmed reduction and temperature programmed desorption indicated that the oxygen defects not only increase the amount of trapped NO x , but also improve the low-temperature redox performance of the catalyst. The lower stability of NO x species adsorbed on oxygen defects promotes the NO x release step in the NSR reaction and benefits the regeneration of storage sites.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2020
·Vol. 23
·期 3
·671-677
·
IF 3.117
Sanzhao Song,Jian Sun,Jing Zhou,Chengzhi Guan,Zhiwei Hu,Ting-Shan Chan,Xian-Long Du,Xiao Lin,Jun Hu,Linjuan Zhang,Jian-Qiang Wang
Molten salts have been reported to be excellent media for the preparation of multicationic oxides, which require harsh conditions to crystallize. Molten salt synthesis provides a wider operational temperature range (usually extends to 1000 °C) and faster mass transport and nucleation processes, thus allowing the preparation of crystalline solids, which require higher temperatures, such as perovskites. However, the mechanisms that control the solid-state formation and phase selection are poorly understood. Herein, several typical molten alkali metal halide (Cl−) and oxosalt (CO32− and SO42−) systems were employed as the reaction media for the synthesis of LaCoO3 (LCO) crystals, and the effects of ionic salt species on the morphological, geometric and electronic structures of LCO crystals were examined by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray absorption spectroscopy (XAS). The LCO perovskite was successfully synthesized in a molten NaCl–KCl eutectic mixture at 700 °C, which was lower than that used for the conventional mixed oxide synthesis. Our results show that in the molten salt synthesis, the type of reaction medium, calcination temperature, the ratio of salt, and reaction time govern the microscopic mechanisms in the preparation of multicationic oxides. Most importantly, we observed that LaOCl was formed as an intermediate, which plays a key role in the reaction pathway for the phase-selective synthesis of perovskite LCO.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Sustainability
·
2022
·
IF 7.244
R. Zeng,G. Jin,D. He,L. Zhang,D. Chen,Y. Zhang,L. Zhu,Y. Mei,W. Wu,Y. Luo
Utilizing propane and CO 2 as coreactants to produce syngas (CO/H 2 ) via dry reforming shows several advantages over direct propane dehydrogenation and traditional methane dry reforming . It is of great importance to establish high-efficiency catalytic systems that can break C–C bonds and activate CO 2 simultaneously. Herein, acidic H 2 O 2 was applied to etch LaCoO 3 . Surprisingly, highly dispersed Co 3 O 4 at the edges of support along with high oxygen vacancies were obtained from acidic H 2 O 2 treatment. Furthermore, the treated LaCoO 3 catalyst facilitated the generated intermediates of formate to convert into the desired products. The results showed that acidic H 2 O 2 treated LaCoO 3 catalyst can reach 18% for propane conversion and 35% for CO 2 conversion at 550 °C, showing high catalytic activity . Consequently, the present work provides some ideas for the synthesis of efficient LaCoO 3 catalysts for dry reforming of propane.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Kuncan Wang,Junjie Huang,Wen Li,Jiale Huang,Daohua Sun,Xuebin Ke,Qingbiao Li
With the assistance of plant extracts, the facile synthesis of three-dimensional (3D) porous LaCoO3 perovskite is reported at a lower calcination temperature of 500 °C. The formation mechanism is carefully studied by investigating the different roles of organic and inorganic components in Cacumenplatycladi extract. The results indicate that organic components (mainly phenolic acids) function as the similar complex species of citric acid, while the mineral nutrients (Na+, K+, Ca2+, and Mg2+) together with NO3– serve as combustion-aid agents even with trace amounts. Moreover, the biosynthesized LaCoO3 has a high surface area of 32.5 m2 g–1 and exhibits excellent catalytic performance for benzene oxidation. Benzene of 1000 ppm can achieve a stable conversion above 90% at 285 °C in a continuous run for 80 h (weight-hourly space velocity (WHSV) = 40 000 mL g–1 h–1). It can be attributed to the bio-LaCoO3 with more electrophilic adsorption of oxygen species and 3D porous structure.
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
CHEMPHYSCHEM
·
2022
·Vol. 24
·期 6
·e202200845
·
IF 3.52
Ting Wang,Haocheng He,Zihan Meng,Siran Li,Ming Xu,Xueting Liu,Yuan Zhang,Mei Liu,Ming Feng
Graphical A novel “mixed-valent cobalt modulation” strategy is presented to enhance the electrocatalytic oxygen evolution reaction (OER) performance of perovskite LaCoO 3 (LCO). An optimized catalyst with 1.98 % Co 2+ /Co 3+ exhibits a significant magnetic-field enhancement for the OER activity. Extensive efforts to enhance the oxygen evolution reaction (OER) catalytic performance of transition metal oxides mainly concentrate on the extrinsic morphology tailoring, lattice doping, and electrode interface optimizing. Nevertheless, little room is left for performance improvement using these methods and an obvious gap still exists compared to the precious metal catalysts. In this work, a novel “mixed-valent cobalt modulation” strategy is presented to enhance the electrocatalytic OER of perovskite LaCoO 3 (LCO) oxide. The valence transition of cobalt is realized by ethylenediamine post reduction procedure at room temperature, which further induces the variation of magnetic properties for LCO catalyst. The optimized LCO catalyst with Co 2+ /Co 3+ of 1.98 % exhibits the best OER activity, and the overpotential at 10 mA cm −2 current density is decreased by 170 mV compared pristine LCO. Impressively, the ferromagnetic LCO catalyst can perform magnetic OER enhancement. By application of an external magnetic field, the overpotential of LCO at 10 mA cm −2 can be further decreased by 20 mV compared to that of under zero magnetic field, which arises from the enhanced energy states of electrons and accelerated electron transfer process driven by magnetic field. Our findings may provide a promising strategy to break the bottleneck for further enhancement of OER performance.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Inorganic Chemistry Frontiers
·
2025
·
IF 6.4
Jie Tu,Siyuan Du,Hangren Li,Jing Xia,Longyuan Shi,Jianjun Tian,Linxing Zhang
Strain engineering has emerged as a powerful strategy for optimizing the material structure and enhancing performance across a wide range of applications. Herein, we report the deployment of substrate-imposed strain to govern the dissolution kinetics of an epitaxial sacrificial layer. The epitaxial LaCoO3 (LCO) has been employed as a sacrificial layer: a lattice-matched and environmentally benign perovskite for releasing freestanding oxide membranes. Intriguingly, the decomposition efficiency of LCO can be precisely controlled by the substrate strain, whether tensile or compressive, which can induce changes in chemical bonds and lattice distortion, thereby altering the reactivity of LCO with the decomposition solution. Under a tensile strain of 2.09% on SrTiO3 substrate, the decomposition efficiency of LCO was accelerated by 66.7% compared with that on LaAlO3 substrate with compressive strain. Synchrotron X-ray absorption spectroscopy, high-angle annular dark-field scanning transmission electron microscopy and semi-in situ optical absorption spectra reveal that tensile strain reduces La–O bond energy and enhances octahedral distortion, making the lattice more susceptible to collapse. Furthermore, freestanding PbZrO3 films were fabricated using the LCO sacrificial layer, showing a ferroelectric-to-antiferroelectric transition. These findings underscore the potential of strain engineering in controlling material properties and fabrication processes, offering new strategies for developing flexible electronic devices.
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2020
·
IF 3.687
Junjie Huang,Kuncan Wang,Xintong Huang,Jiale Huang
With the assistance of nitrate additives (KNO 3 , NaNO 3 , Ca(NO 3 ) 2 or Mg(NO 3 ) 2 ), perovskite LaCoO 3 , which has a 3D porous structure and relatively high surface area (around 20 m 2 /g) was successfully synthesized at 500 °C via a sol-gel process. The results of thermal gravimetric analysis indicated that nitrates (especially NaNO 3 and KNO 3 ) acted as combustion aids, which significantly lowered down the crystallization temperature of LaCoO 3 by intensifying the decomposition of organic ingredients. Unlike other researches, the metal ions from the nitrate additives did not dope into the crystal lattice of perovskite and it was found that the remained nitrate additives would dramatically inhibit the LaCoO 3 catalytic activity on benzene oxidation. However, after removal of these remained nitrate additives by rinsing with deionized water, LaCoO 3 derived from our proposed salt-assisted sol-gel method exhibited an excellent catalytic activity.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
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