Catalysts
·
2019
·Vol. 9
·期 3
·288
·
IF 3.444
Feihu Liu,Zhong Wang,Da Wang,Dan Chen,Fushan Chen,Xuebing Li
The CeO2ordinary amorphous, nanopolyhedrons, nanorods, and nanocubes were prefabricated by the hydrothermal method, and employed as carriers of Fe/W–CeO2catalysts to selectively catalyze the reduction of NO with ammonia. Characterization results indicated that the morphology of CeO2support originated from selectively exposing different crystal surfaces, which has a significant effect on oxygen vacancies, acid sites and the dispersion of Fe2O3. The CeO2nanopolyhedrons catalyst (Fe/W–CeO2–P) showed most oxygen vacancies, the largest the quantity of acid sites, the largest BET (Brunauer-Emmett-Teller) surface area and the best dispersion of Fe2O3, which was associated with predominately exposing CeO2(111) planes. Consequently, the Fe/W–CeO2–P catalyst has the highest NO conversion rate in the temperature range of 100–325 °C among the ordinary amorphous, nanorods, and nanocubes Fe/W–CeO2catalysts.Keywords:morphology;Fe/W–CeO2;nanopolyhedra;CeO2(111) planes
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 28
·9744-9756
·
IF 4
Yanxia Wang,Xiude Hu
The development of new, efficient noble-metal-free photocatalysts is of great significance for the photocatalytic hydrogen evolution reaction. Herein, Co9S8 with a hollow polyhedral structure was synthesized by in situ sulfurization of ZIF-67, and subsequently, Co9S8@Ni2P composite photocatalytic materials were prepared by loading Ni2P on the surface of Co9S8 through a solvothermal method based on a morphology regulation strategy. The design of the 3D@0D spatial structure of Co9S8@Ni2P is favorable for the formation of photocatalytic hydrogen evolution active sites. Due to the excellent metal conductivity of Ni2P, Ni2P as a cocatalyst can accelerate the separation of photogenerated electrons from holes in Co9S8, thus providing a large number of available photogenerated electrons for photocatalytic reactions. It is worth mentioning that a Co–P chemical bond is formed between Co9S8 and Ni2P, which plays an active role in the transport of photogenerated electrons. The densities of states of Co9S8 and Ni2P were determined by density functional theory (DFT) calculations. The reduction of the hydrogen evolution overpotential and the formation of efficient charge-carrier transport channels on Co9S8@Ni2P were confirmed by a series of electrochemical and fluorescence tests. This study provides a new idea for the design of highly active noble-metal-free materials for the photocatalytic hydrogen evolution reaction.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2023
·Vol. 25
·期 19
·2939-2945
·
IF 3.1
Jingdong Yan,Dongdong Chu,Fangfang Zhang,Zhihua Yang,Shilie Pan,Xueling Hou
By the introduction of trivalent rare-earth metal-centered polyhedra [LnO6F4] (Ln = La, Gd) into alkali metal sulfates, two novel sulfate fluorides, NaLn2(SO4)2F3 (Ln = La, Gd), were successfully synthesized via a high-temperature solution method in sealed quartz tubes. The two compounds are isomorphic and feature a structure composed of [LnO6F4] (Ln = La, Gd) polyhedra, [NaO4F3] polyhedra, and [SO4] groups. The UV-vis-NIR diffuse reflection spectra, infrared spectra, and thermal stability are also presented. Meanwhile, theoretical calculations reveal that NaLa2(SO4)2F3 has a moderate birefringence (0.041 at 1064 nm) which is significantly improved compared with Na2SO4. And the enhancement of birefringence can be ascribed to the introduction of rare-earth metal-centered polyhedra by a real space atom-cutting method. This work shows that the introduction of trivalent rare-earth metal-centered polyhedra is one of the effective strategies for bolstering the birefringence performance of non-π-conjugated sulfate systems.
研究领域:
材料科学
·
光学材料
·
无机化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Songrong Li,Xi Chen,Mingjie Li,Cheng Xue,Yuhan Long,Wenhao Liu,Zhenhua Cao,Xiaoqin Tong,Wenli Huang,Dongfang Liu
In this study, hollow Co 3 S 4 polyhedron decorated with interlayer-expanded MoS 2 nanosheets (Co 3 S 4 -MoS 2 ) was devised and applied to absorb tetracycline (TC) from aqueous solution. The adsorption performances and mechanisms were systematically explored. The experimental results indicated that the adsorption kinetics well-fitted the pseudo-second-order kinetics model and the adsorption isotherms followed the Langmuir model. In terms of Langmuir model, the maximum adsorption capacity of Co 3 S 4 -MoS 2 was achieved with a record-high value of 1667.14 mg/g at 308 K, which was much higher than that of other reported adsorbents. The excellent adsorption performance of the adsorbent toward TC was presented under a wide pH range (3.0–8.0) and was enhanced by the addition of salinity. The high adsorption capacity of Co 3 S 4 -MoS 2 depended on the combined effects of multi-affinities including π-π interaction, hydrophobic effect, surface complexation and hydrogen bonding. These results suggested that Co 3 S 4 -MoS 2 was a high-efficiency adsorbent for treating wastewater that contains TC and provided new insights into the design of other hollow metal sulfides nanomaterials to treat antibiotic-containing wastewater.
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
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Xianke Zhang,Suqiong Xu,Zhiqian Yao,Xiaoqing Liu,Jujun Yuan,Fangguang Kuang,Shuying Kang,Huajun Yu
Single-phase materials with exchange bias (EB) effect at room temperature (RT) are very important for future applications in spintronic devices, magnetic storage, and sensors. To explore materials showing the EB effect at RT is an interesting and important issue. In this paper, LaFeO 3 micro-polyhedrons composed of an average particle size of 66 nm nanoparticles have been synthesized by annealing LaFe(CN) 6 precursors in air at 630 °C for 8 h. Magnetic hysteresis loops show that LaFeO 3 micro-polyhedrons present a large spontaneous EB (SEB) effect ( ∼ 1.5 kOe) at RT after zero-field cooling (ZFC) and a gigant conventional EB (CEB) effect ( ∼ 5.6 kOe) after field cooling (FC) of 70 kOe. To the best of our knowledge, the current compound shows the largest negative EB field after ZFC at RT among SEB materials discovered so far. The successful fitting of training effect (TE) data with Binek’s model shows that the origin of SEB lies in the interface exchange coupling between different magnetic phases. The interface with the “pinning” effect of antiferromagnetic (AFM) matrix relative to ferromagnetic (FM) clusters exhibits unidirectional anisotropy, which is formed during the initial magnetization process. This interesting finding of the SEB effect at RT in single-phase perovskite LaFeO 3 system may open a new direction for possible technological applications.
研究领域:
材料科学
·
磁学
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2018
·Vol. 5
·期 8
·1787-1794
·
IF 5.106
Yanna Chen,Min Zhang,Cong Hu,Zhihua Yang,Shilie Pan
As the first reported examples of borates in the Zn–Sc–B–O system, Ba2ZnSc(BO3)3 and Ba4Zn5Sc2(BO3)8 were synthesized through a high-temperature solution method. The structure of Ba2ZnSc(BO3)3 can be described as ZnO4 tetrahedra connecting ScO6 octahedra to form a [ZnScO9]13− dimer, which further bonds with seven BO3 triangles to form a 2∞[ZnSc(BO3)3] layer, and the Ba atoms distribute in the voids between the layers. In contrast, in Ba4Zn5Sc2(BO3)8, Zn–O chains composed of 4- and 6-coordinated Zn atoms link with Sc2O8 dimers to form a Zn–Sc–O layer, and the BO3 triangles and Ba atoms fill in the voids between the layers. Interestingly, the special [Zn2(BO3)6]14− cluster is found in Ba2ZnSc(BO3)3, which is different from the 2D layers or 3D frameworks of the Zn–B–O configurations in other zincoborates. Moreover, the lowest-coordinated ScO5 polyhedra, as well as the coexistence of two types of ZnOn units (n = 4 and 6), are observed for the first time in Ba4Zn5Sc2(BO3)8. These fascinating results can promote the design of novel borates with BO3 units and enrich the borate structure chemistry.
研究领域:
材料科学
·
晶体化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2021
·Vol. 45
·期 9
·13040-13054
·
IF 5.164
Peng Su,Hai Liu,Qingxiang Ma,Zhiliang Jin
Summary The photocatalytic hydrogen evolution reaction is one of the important ways to convert solar energy into renewable hydrogen. In this work, the Co 9 S 8 hollow polyhedron was formed after sulfidation and calcination with the metal-organic framework ZIF-67. The hollow polyhedron Co 9 S 8 provides abundant support sites for Mn 0.05 Cd 0.95 S and effectively reduces the agglomeration degree of Mn 0.05 Cd 0.95 S. The Co 9 S 8 hollow polyhedron as the reaction site has a large specific surface area and a mesoporous structure, which is beneficial to the progress of the photocatalytic reaction. A series of tests showed that the introduction of Co 9 S 8 hollow polyhedron significantly improved the light-trapping ability and exposed more reaction sites. Co 9 S 8 hollow polyhedrons are used as electron capture sites, which can effectively collect electrons and induce the interface charge transfer of Mn 0.05 Cd 0.95 S to Co 9 S 8 . Because the Co 9 S 8 -Mn 0.05 Cd 0.95 S composite catalyst had a strong light-trapping ability, abundant reaction sites and Co 9 S 8 -Mn 0.05 Cd 0.95 S heterojunction accelerate the separation and transfer of charges. Therefore, the hydrogen evolution rate of the 10%Co 9 S 8 -Mn 0.05 Cd 0.95 S composite catalyst was relatively high, which was 13.369 mmol g −1 h −1 . In addition, the 10%Co 9 S 8 -Mn 0.05 Cd 0.95 S composite catalyst still has good hydrogen evolution stability after four cycles. This research may supply a new idea for the preparation of high-efficiency photocatalysts with hollow structures. Novelty Statement The Co 9 S 8 hollow polyhedron provides abundant support sites for M 0.05 C 0.95 S particles, which effectively reduces the degree of agglomeration. The Co 9 S 8 -M 0.05 C 0.95 S heterojunction catalyst not only accelerates the migration and transfer of electrons, but also provides abundant reaction sites. Therefore, the Co 9 S 8 -M 0.05 C 0.95 S composite catalyst has good catalytic activity.
研究领域:
材料科学
·
能源化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2025
·
IF 16
Hairui Huang,Hanyu Wu,Yizhou Zhang,Xunda Feng
Molecular-scale adsorption, catalysis, and separation demand nanoporous materials with high permeability, extensive surface areas, and pronounced nanoconfined effects. Fabricating polymeric particles with 3-D interwoven pores of ∼1 nm potentially addresses these needs. However, significant challenges remain in controlling their pore interconnectivity, uniformity, and achieving faceted particle shapes. Herein we present facile fabrication of polyhedral particles possessing interpenetrating 1 nm pores by suspension polymerization of double-gyroid (DG) liquid crystalline droplets. Mechanical stirring of the disordered phase at elevated temperatures, followed by undercooling, leads to the emulsification of DG droplets, as confirmed by synchrotron small-angle X-ray scattering (SAXS). UV-induced cross-linking of the DG droplets preserves the ordered network of 1 nm pores, as characterized by SAXS and microscopy. Intriguingly, due to the elasticity induced by the Ia3̅d periodicities, these particles adopt polyhedral shapes to avoid the elastic energy penalty associated with conventional sphericity. We demonstrate that these faceted particles, featuring 1 nm pores and efficient packing, enable rapid, size-exclusive adsorption and nanoconfined degradation of organic pollutants, driven by their 3-D permeability, high surface area, and enhanced nanoconfinement effects.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2020
·
IF 6.215
Xueying Li,Yalin Xu,Hui Wu,Xiu Qian,Lizhuang Chen,Yuanyuan Dan,Qing Yu
The porous Fe 3 O 4 nanoaggregates were fabricated by the carbon polyhedron as templates through the hydrothermal method . The carbon polyhedron was obtained by the carbonization of ZIF-67 and subsequent acid treatment. The finial porous Fe 3 O 4 nanoaggregates possess high specific area of 547.5 m 2 g −1 with pore volume of 0.375 cm 3 g −1 . Such unique structures facilitate electrode materials fully exposed to electrolyte solution and maintain the structural stability during fast electrochemical reaction processes. Thereby, porous Fe 3 O 4 nanoaggregates exhibit high specific capacity of 868.7 C g −1 at 2 A g −1 in the wide potential window of −0.90 - 0.45 V in 3 M KOH. After 3000 cycles at 2 A g −1 , the electrode material retains 771.8 C g −1 . Even at high current density of 20 A g −1 , the electrode still delivers 456.1 C g −1 , which is outstanding of other Fe 3 O 4 nanomaterial for supercapacitor . Furthermore, the Fe 3 O 4 //AC asymmetry supercapacitor (3 M KOH as electrolyte) exhibits high energy density of 24.2 Wh kg −1 at power density of 801.1 W kg −1 with excellent cycling performance.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Small Methods
·
2023
·Vol. 7
·期 7
·2300121
·
IF 12.4
Gaoyan Xiong,Chao Feng,Hsiao-Chien Chen,Junxi Li,Fei Jiang,Shu Tao,Yunxia Wang,Yichuan Li,Yuan Pan
This study adopts a facile and effective in situ encapsulation-oxidation strategy for constructing a coupling catalyst composed of atomically dispersed Pt-doped Co 3 O 4 spinel nanoparticles (NPs) embedded in polyhedron frames (PFs) for robust propane total oxidation. Benefiting from the abundant oxygen vacancies and more highly valent active Co 3+ species caused by the doping of Pt atoms as well as the confinement effect, the optimized 0.2Pt-Co 3 O 4 NPs/PFs catalyst exhibits excellent propane catalytic activity with low T 90 (184 °C), superior apparent reaction rate (21.62×10 8 (mol g cat −1 s −1 )), low apparent activation energy ( E a = 17.89 kJ mol −1 ), high turnover frequency ( 811×10 7 (mol g cat −1 s −1 )) as well as good stability. In situ diffuse reflectance infrared Fourier transform spectroscopy and density functional theory calculations indicate that the doping of Pt atoms enhances the oxygen activation ability, and decreases the energy barrier required for C H bond breaking, thus improving the deep oxidation process of the intermediate species. This study opens up new ideas for constructing coupling catalysts from atomic scale with low cost to enhance the activation of oxygen molecules and the deep oxidation of linear short chain alkanes at low temperature.
研究领域:
化学工程
·
材料科学
·
催化反应
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2018
·
IF 0
Yahui Wang,Chaolong Li,Xijiang Han,Dawei Liu,Honghong Zhao,Zhennan Li,Ping Xu,Yunchen Du
Carbides/carbon composites are becoming a new kind of microwave absorption (MA) materials with great potential in chemical stability and light weight, as well as enhanced performance. Herein, we design a series of Mo2C/C composites through a simple pyrolysis of Mo-substituted ZIF-8 (Mo/ZIF-8). It is found that the transformation of zeolitic imidazolate frameworks into carbon polyhedrons is accompanied by the in situ formation of ultrasmall Mo2C nanoparticles (Mo2C NPs) less than 5.0 nm. The molar ratio of 2-methylimidazole to molybdic acid (MIM/Mo) presents a significant effect on the relative content of Mo2C NPs but not on their average size. The uniform distribution of Mo2C NPs in carbon polyhedrons overcomes the poor chemical homogeneity in conventional carbides/carbon composites. More importantly, Mo2C NPs modulate the dielectric loss of these composites effectively. On one hand, they moderately weaken the contribution from conductivity loss and dipole orientation polarization; on the other hand, they create considerable interfacial polarization. As a result, these Mo2C/C composites display much better impedance matching than individual carbon polyhedrons. When the MIM/Mo ratio reaches 6.0, the optimized composite, S-Mo2C/C-6.0, displays good MA performance in the frequency range of 2.0–18.0 GHz, including powerful reflection loss and broad qualified bandwidth. Its performance is actually superior to those conventional carbides/carbon composites in previous studies, demonstrating that Mo2C/C composite from this novel strategy may be a promising candidate for high-performance MA materials in the future.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
Journal of the Taiwan Institute of Chemical Engineers
·
2019
·
IF 3.834
Mo Qiu,Ruoqing Wang,Xinhua Qi
This paper reports a method of controllable synthesis of hollow polyhedral α-Fe 2 O 3 using H 3 btc and HF as additives. Three products with different morphologies were obtained by only adjusting the ratio of H 3 btc: HF. The as-prepared products were characterized using XRD, TG-DSC, FT-IR, Zeta potential analysis, UV, SEM and TEM. The characterization results reveal that H 3 btc is the key factor in preparing a hollow structure, and HF is vital to form a polyhedral morphology. On the basis of the time-dependent experiments, a probable growth mechanism of α-Fe 2 O 3 was proposed. Finally, the resulting hollow polyhedral α-Fe 2 O 3 exhibit good photocatalytic degradative ability for rhodamine B (RhB) molecules in water under visible light irradiation.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）