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Article: Excellent NiO–Ni Nanoplate Microwave Absorber via Pinning Effect of Antiferromagnetic–Ferromagnetic Interface

You, Wenbin / Renchao Che

ACS applied materials & interfaces. 2018 Apr. 13, v. 10, no. 17

2018

Abstract: Materials with strong magnetic property that can provide excellent microwave absorption performance are highly desirable, especially if their dielectric and magnetic properties can be easily modulated, which make minimal thickness and ultrawide bandwidth ...

Abstract	Materials with strong magnetic property that can provide excellent microwave absorption performance are highly desirable, especially if their dielectric and magnetic properties can be easily modulated, which make minimal thickness and ultrawide bandwidth become achievable. The magnetic properties of ferromagnetic (FM) and antiferromagnetic (AFM) composite materials are closely related to their ratio of composition, size, morphology, and structure. AFM–FM composites have become a popular alternative for microwave absorption; however, the controllable design and preparation need to be urgently optimized. Here, we have successfully prepared a series of platelike NiO–Ni composites and demonstrated the potential of such composites for microwave absorption. Strong magnetic coupling was found from NiO–Ni nanoparticles by electron holography, which makes NiO–Ni composites a highly efficient microwave absorber (strong reflection loss: −61.5 dB and broad bandwidth: 11.2 GHz, reflection loss < −10 dB). Our findings are helpful to develop a strong microwave absorber based on magnetic coupling.
Keywords	absorption ; composite materials ; ferrimagnetic materials ; holography ; magnetic properties ; magnetism ; nanoparticles
Language	English
Dates of publication	2018-0413
Size	p. 15104-15111.
Publishing place	American Chemical Society
Document type	Article
ISSN	1944-8252
DOI	10.1021/acsami.8b03610
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Respective Roles of Inner and Outer Carbon in Boosting the K+ Storage Performance of Dual‐Carbon‐Confined ZnSe

Jiafeng Ruan / Jiahe Zang / Jiaming Hu / Renchao Che / Fang Fang / Fei Wang / Yun Song / Dalin Sun

Advanced Science, Vol 9, Iss 5, Pp n/a-n/a (2022)

2022

Abstract: Abstract Potassium‐ion batteries (PIBs) have been considered as potential alternatives for lithium‐ion batteries since there is a demand for better anode with superior energy, excellent rate capability, and long cyclability. The high‐capacity zinc ... ...

Abstract	Abstract Potassium‐ion batteries (PIBs) have been considered as potential alternatives for lithium‐ion batteries since there is a demand for better anode with superior energy, excellent rate capability, and long cyclability. The high‐capacity zinc selenide (ZnSe) anode, which combines the merits of conversion and alloying reactions, is promising for PIBs but suffers from poor cyclability and low electronic conductivity. To effectively boost electrochemical performance of ZnSe, a “dual‐carbon‐confined” structure is constructed, in which an inner N‐doped microporous carbon (NMC)‐coated ZnSe wrapped by outer‐rGO (ZnSe@i‐NMC@o‐rGO) is synthesized. Combining finite element simulation, dynamic analysis, and density functional theory calculations, the respective roles of inner‐ and outer‐carbon in boosting performance are revealed. The inner‐NMC increased the reactivity of ZnSe with K+ and alleviated the volume expansion of ZnSe, while outer‐rGO further stabilized the structure and promoted the reaction kinetics. Benefiting from the synergistic effect of dual‐carbon, ZnSe@i‐NMC@o‐rGO exhibited a high specific capacity 233.4 mAh g−1 after 1500 cycles at 2.0 A g−1. Coupled with activated carbon, a potassium‐ion hybrid capacitor displayed a high energy density of 176.6 Wh kg−1 at 1800 W kg−1 and a superior capacity retention of 82.51% at 2.0 A g−1 after 11000 cycles.
Keywords	dual‐carbon confined strategy ; inner MOF‐derived N‐doped microporous carbon ; outer 2D‐rGO ; potassium‐ion batteries ; ZnSe ; Science ; Q
Subject code	541
Language	English
Publishing date	2022-02-01T00:00:00Z
Publisher	Wiley
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Multiprincipal Element M2FeC (M = Ti,V,Nb,Ta,Zr) MAX Phases with Synergistic Effect of Dielectric and Magnetic Loss

Lu Chen / Youbing Li / Biao Zhao / Shanshan Liu / Huibin Zhang / Ke Chen / Mian Li / Shiyu Du / Faxian Xiu / Renchao Che / Zhifang Chai / Qing Huang

Advanced Science, Vol 10, Iss 10, Pp n/a-n/a (2023)

2023

Abstract: Abstract Electromagnetic (EM) wave pollution is harmful to human health and environment, thus it is absolutely important to develop new electromagnetic wave absorbing materials. MAX phases have been attracted more attention as a potential candidate for ... ...

Abstract	Abstract Electromagnetic (EM) wave pollution is harmful to human health and environment, thus it is absolutely important to develop new electromagnetic wave absorbing materials. MAX phases have been attracted more attention as a potential candidate for electromagnetic wave absorbing materials due to their high conductivity and nanolaminated structure. Herein, two new magnetic MAX phases with multiprincipal elements ((Ti1/3Nb1/3Ta1/3)2FeC and (Ti0.2V0.2Nb0.2Ta0.2Zr0.2)2FeC) in which Fe atoms replace Al atoms in the A sites are successfully synthesized by an isomorphous replacement reaction of multiprincipal (Ti1/3Nb1/3Ta1/3)2AlC and (Ti0.2V0.2Nb0.2Ta0.2Zr0.2)2AlC MAX phases with Lewis acid salt (FeCl2). (Ti1/3Nb1/3Ta1/3)2FeC and (Ti0.2V0.2Nb0.2Ta0.2Zr0.2)2FeC exhibit ferromagnetic behavior, and the Curie temperature (Tc) are 302 and 235 K, respectively. The dual electromagnetic absorption mechanisms that include dielectric and magnetic loss, which is realized in these multiprincipal MAX phases. The minimum reflection loss (RL) of (Ti1/3Nb1/3Ta1/3)2FeC is −44.4 dB at 6.56 GHz with 3 mm thickness, and the effective bandwidth is 2.48 GHz. Additionally, the electromagnetic wave absorption properties of the magnetic MAX phases indicate that magnetic loss also plays an important role besides dielectric loss. This work shows a promising composition‐design strategy to develop MAX phases with good EM wave absorption performance via simultaneously regulating dielectric and magnetic loss together.
Keywords	dielectric loss ; electromagnetic wave absorption ; magnetic loss ; magnetic MAX phases ; multiprincipal elements ; Science ; Q
Subject code	535
Language	English
Publishing date	2023-04-01T00:00:00Z
Publisher	Wiley
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: One-dimensionally oriented self-assembly of ordered mesoporous nanofibers featuring tailorable mesophases via kinetic control

Liang Peng / Huarong Peng / Steven Wang / Xingjin Li / Jiaying Mo / Xiong Wang / Yun Tang / Renchao Che / Zuankai Wang / Wei Li / Dongyuan Zhao

Nature Communications, Vol 14, Iss 1, Pp 1-

2023 Volume 11

Abstract: Abstract One-dimensional (1D) nanomaterials have sparked widespread research interest owing to their fascinating physicochemical properties, however, the direct self-assembly of 1D porous nanomaterials and control over their porosity still presents a ... ...

Abstract	Abstract One-dimensional (1D) nanomaterials have sparked widespread research interest owing to their fascinating physicochemical properties, however, the direct self-assembly of 1D porous nanomaterials and control over their porosity still presents a grand challenge. Herein, we report a monomicelle oriented self-assembly approach to fabricate 1D mesoporous nanostructures with uniform diameter, high aspect ratio and ordered mesostructure. This strategy features the introduction of hexamethylenetetramine as a curing agent, which can subtly control the monomicelle self-assembly kinetics, thus enabling formation of high-quality 1D ordered mesostructures. Meanwhile, the micellar structure can be precisely manipulated by changing the reactant stoichiometric ratio, resulting in tailorable mesophases from 3D cubic (Im-3m) to 2D hexagonal (p6mm) symmetries. More interestingly, the resultant mesoporous nanofibers can be assembled into 3D hierarchical cryogels on a large scale. The 1D nanoscale of the mesoporous nanofibers, in combination with small diameter (~65 nm), high aspect ratio (~154), large surface area (~452 m2 g−1), and 3D open mesopores (~6 nm), endows them with excellent performances for sodium ion storage and water purification. Our methodology opens up an exciting way to develop next-generation ordered mesoporous materials for various applications.
Keywords	Science ; Q
Language	English
Publishing date	2023-12-01T00:00:00Z
Publisher	Nature Portfolio
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Staggered circular nanoporous graphene converts electromagnetic waves into electricity

Hualiang Lv / Yuxing Yao / Shucong Li / Guanglei Wu / Biao Zhao / Xiaodi Zhou / Robert L. Dupont / Ufuoma I. Kara / Yimin Zhou / Shibo Xi / Bo Liu / Renchao Che / Jincang Zhang / Hongbin Xu / Solomon Adera / Renbing Wu / Xiaoguang Wang

Nature Communications, Vol 14, Iss 1, Pp 1-

2023 Volume 9

Abstract: The electromagnetic (EM) energy released by electronic devices in the environment is largely wasted and contributes to EM pollution. Here, the authors report the synthesis of staggered circular nanoporous graphene enabling the absorption and conversion ... ...

Abstract	The electromagnetic (EM) energy released by electronic devices in the environment is largely wasted and contributes to EM pollution. Here, the authors report the synthesis of staggered circular nanoporous graphene enabling the absorption and conversion of EM waves into electricity via the thermoelectric effect.
Keywords	Science ; Q
Language	English
Publishing date	2023-04-01T00:00:00Z
Publisher	Nature Portfolio
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Customizing Heterointerfaces in Multilevel Hollow Architecture Constructed by Magnetic Spindle Arrays Using the Polymerizing‐Etching Strategy for Boosting Microwave Absorption

Chunyang Xu / Panbo Liu / Zhengchen Wu / Huibin Zhang / Ruixuan Zhang / Chang Zhang / Lei Wang / Longyuan Wang / Bingtong Yang / Ziqi Yang / Wenbin You / Renchao Che

Advanced Science, Vol 9, Iss 17, Pp n/a-n/a (2022)

2022

Abstract: Abstract Heterointerface engineering is evolving as an effective approach to tune electromagnetic functional materials, but the mechanisms of heterointerfaces on microwave absorption (MA) remain unclear. In this work, abundant electromagnetic ... ...

Abstract	Abstract Heterointerface engineering is evolving as an effective approach to tune electromagnetic functional materials, but the mechanisms of heterointerfaces on microwave absorption (MA) remain unclear. In this work, abundant electromagnetic heterointerfaces are customized in multilevel hollow architecture via a one‐step synergistic polymerizing‐etching strategy. Fe/Fe3O4@C spindle‐on‐tube structures are transformed from FeOOH@polydopamine precursors by a controllable reduction process. The impressive electromagnetic heterostructures are realized on the Fe/Fe3O4@C hollow spindle arrays and induce strong interfacial polarization. The highly dispersive Fe/Fe3O4 nanoparticles within spindles build multi‐dimension magnetic networks, which enhance the interaction with incident microwaves and reinforce magnetic loss capacity. Moreover, the hierarchically hollow structure and electromagnetic synergistic components are conducive to the impedance matching between absorbing materials and air medium. Furthermore, the mechanisms of electromagnetic heterointerfaces on the MA are systematically investigated. Accordingly, the as‐prepared hierarchical Fe/Fe3O4@C microtubes exhibit remarkable MA performance with a maximum refection loss of −55.4 dB and an absorption bandwidth of 4.2 GHz. Therefore, in this study, the authors not only demonstrate a synergistic strategy to design multilevel hollow architecture, but also provide a fundamental guide in heterointerface engineering of highly efficient electromagnetic functional materials.
Keywords	heterointerfaces ; microtube ; microwave absorption ; multilevel hollow architecture ; nanospindle arrays ; Science ; Q
Subject code	535
Language	English
Publishing date	2022-06-01T00:00:00Z
Publisher	Wiley
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Room-Temperature Response Performance of Coupled Doped-Well Quantum Cascade Detectors with Array Structure

Jie Chen / Fengwei Chen / Xuemin Wang / Yunhao Zhao / Yuyang Wu / Qingchen Cao / Tao Jiang / Keyu Li / Yang Li / Jincang Zhang / Weidong Wu / Renchao Che

Nanomaterials, Vol 13, Iss 1, p

2022 Volume 110

Abstract: Energy level interaction and electron concentration are crucial aspects that affect the response performance of quantum cascade detectors (QCDs). In this work, two different-structured array QCDs are prepared, and the detectivity reaches 10 9 cm·Hz 1/2 / ... ...

Abstract	Energy level interaction and electron concentration are crucial aspects that affect the response performance of quantum cascade detectors (QCDs). In this work, two different-structured array QCDs are prepared, and the detectivity reaches 10 9 cm·Hz 1/2 /W at room temperature. The overlap integral (OI) and oscillator strength (OS) between different energy levels under a series of applied biases are fitted and reveal the influence of energy level interaction on the response performance. The redistribution of electrons in the cascade structure at room temperatures is established. The coupled doped-well structure shows a higher electron concentration at room temperature, which represents a high absorption efficiency in the active region. Even better responsivity and detectivity are exhibited in the coupled doped-well QCD. These results offer a novel strategy to understand the mechanisms that affect response performance and expand the application range of QCDs for long-wave infrared (LWIR) detection.
Keywords	QCD ; responsivity ; energy level interactions ; electron concentration ; doping ; Chemistry ; QD1-999
Subject code	541
Language	English
Publishing date	2022-12-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article: Copper- and Cobalt-Codoped CeO2 Nanospheres with Abundant Oxygen Vacancies as Highly Efficient Electrocatalysts for Dual-Mode Electrochemical Sensing of MicroRNA

Xue, Shuyan / Jie Zhang / Lei Wang / Qingqing Li / Renchao Che / Wenbin You

Analytical chemistry. 2019 Jan. 17, v. 91, no. 4

2019

Abstract: Oxide materials with redox properties have aroused growing interest in many applications. Introducing dopants into crystal lattices provides an effective way to optimize the catalytic activities of the oxides as well as their redox properties. Herein, ... ...

Abstract	Oxide materials with redox properties have aroused growing interest in many applications. Introducing dopants into crystal lattices provides an effective way to optimize the catalytic activities of the oxides as well as their redox properties. Herein, CeO2 nanospheres codoped with Cu and Co (CuCo–CeO2 NSs) were first synthesized and exploited as efficient electrocatalysts for dual-mode electrochemical sensing of microRNA (miRNA). With the doping of Cu and Co into the CeO2 lattice, large amounts of extra oxygen vacancies were generated, remarkably enhancing the redox and electrocatalytic properties of the CeO2 material. The abundant oxygen vacancies of the CuCo–CeO2 NSs were further identified by X-ray photoelectron spectroscopy (XPS), H2 temperature-programmed reduction (H2-TPR), and electron-energy-loss spectroscopy (EELS). Moreover, Mg2+-induced DNAzyme-assisted target recycling was introduced for ultrasensitive determination. The dual-mode sensing with generality was conducted as follows: First, the CuCo–CeO2 NSs acted as a direct redox mediator to generate a differential-pulse-voltammetry (DPV) signal, which was then greatly amplified by the efficient electrocatalysis of CuCo–CeO2 NSs toward H2O2 decomposition. Second, under the electrocatalysis of CuCo–CeO2 NSs, 3,3-diaminobenzidine (DAB) was oxidized to form nonconductive insoluble precipitates (IPs), leading to great amplification of the electrochemical-impedimetric-spectroscopy (EIS) signal. The dual-mode electrochemical sensor showed a wide linear range (0.1 fM to 10 nM) with a low detection limit (33 aM), paving a new way for constructing ultrasensitive electrochemical sensors.
Keywords	catalytic activity ; ceric oxide ; cobalt ; copper ; copper nanoparticles ; electrochemistry ; hydrogen ; hydrogen peroxide ; microRNA ; nanospheres ; oxygen ; sensors (equipment) ; X-ray photoelectron spectroscopy
Language	English
Dates of publication	2019-0117
Size	p. 2659-2666.
Publishing place	American Chemical Society
Document type	Article
ZDB-ID	1508-8
ISSN	1520-6882 ; 0003-2700
ISSN (online)	1520-6882
ISSN	0003-2700
DOI	10.1021/acs.analchem.8b03778
Database	NAL-Catalogue (AGRICOLA)

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Article: Enhanced Polarization from Hollow Cube-like ZnSnO3 Wrapped by Multiwalled Carbon Nanotubes: As a Lightweight and High-Performance Microwave Absorber

Wang, Lei / Qingqing Li / Renchao Che / Xiao Li / Yunhao Zhao

ACS applied materials & interfaces. 2018 June 12, v. 10, no. 26

2018

Abstract: Polarization and conduction loss play fundamentally important roles in the nonmagnetic microwave absorption process. In this paper, a uniform and monodisperse hollow ZnSnO3 cube wrapped by multiwalled carbon nanotubes (ZSO@CNTs) was successfully ... ...

Abstract	Polarization and conduction loss play fundamentally important roles in the nonmagnetic microwave absorption process. In this paper, a uniform and monodisperse hollow ZnSnO3 cube wrapped by multiwalled carbon nanotubes (ZSO@CNTs) was successfully synthesized via facile hydrothermal treatment. A reasonable mechanism related to Ostwald ripening was proposed to design the varied ZSO@CNTs for the special hollow conductive network. Scanning electron microscopy images clearly indicate that reaction temperature is the key factor for the composite structure, which has a significant effect on its electromagnetic properties. Electron holography proves the inhomogeneous distribution of charge density in the ZSO@CNT system, leading to the occurrence of interface polarization. Complex permittivity properties of ZSO@CNT composites under different reaction temperatures were investigated to optimize the morphology that can distinctly enhance microwave absorption performance. The maximum reflection loss that the ZSO@CNT-130 °C composite can reach is −52.1 dB at 13.5 GHz, and the absorption bandwidths range from 11.9 to 15.8 GHz with a thickness as thin as 1.6 mm. Adjusting the simulation thicknesses from 1 to 5 mm, the efficient absorption bandwidth (RL < −10 dB) that the ZSO@CNT composite could reach was 14.16 GHz (88.8% of 2–18 GHz). The excellent microwave absorption performance may be attributed to the synergistic effects of polarization, conduction loss, and special hollow cage structure. It is proposed that the specially controlled structure could provide an effective path for achieving a high-performance microwave absorber.
Keywords	absorption ; carbon nanotubes ; chemical structure ; holography ; hot water treatment ; Ostwald ripening ; scanning electron microscopy ; synergism ; temperature
Language	English
Dates of publication	2018-0612
Size	p. 22602-22610.
Publishing place	American Chemical Society
Document type	Article
ISSN	1944-8252
DOI	10.1021/acsami.8b05414
Database	NAL-Catalogue (AGRICOLA)

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Article: “Matryoshka Doll”-Like CeO2 Microspheres with Hierarchical Structure To Achieve Significantly Enhanced Microwave Absorption Performance

Li, Qingqing / Jiwei Liu / Renchao Che / Wenbin You / Xiao Li / Xuebing Zhao / Yunhao Zhao

ACS applied materials & interfaces. 2018 July 24, v. 10, no. 32

2018

Abstract: Recently, it is still a great challenge to develop a new type of absorber that possesses special advantages of low cost, ultrawide bandwidth, and strong absorption intensity. Herein, the unique “Matryoshka doll”-like CeO2 microspheres with tunable ... ...

Abstract	Recently, it is still a great challenge to develop a new type of absorber that possesses special advantages of low cost, ultrawide bandwidth, and strong absorption intensity. Herein, the unique “Matryoshka doll”-like CeO2 microspheres with tunable interspaces were successfully synthesized by a facile and template-free method. The as-synthesized hierarchical yolk–shell CeO2 microspheres were constructed by a layer of outer shell and multiple inner cores. The interspace gap of the microspheres can be simply adjusted only by altering the solvothermal reaction time. Simultaneously, Ostwald ripening, Kirkendall effect, and self-etching process contribute a synergetic growth mechanism responsible for this amazing hierarchical architecture. Importantly, the “Matryoshka doll”-like CeO2 microspheres exhibited significantly strong microwave absorption in the frequency range of 2–18 GHz, with a reflection loss of −71.3 dB at 14.5 GHz and an effective absorption bandwidth of 5.4 GHz (<−10 dB), which is superior to the multicomponent absorbers. Such an outstanding microwave absorption performance stems from the unique hierarchical yolk–shell structure and the designable interspaces, leading to the multiple scattering, interfacial polarization, and plasma dielectric oscillation from the abundant interfaces and curved surfaces, which can be illustrated by the related results from electron holography and electron energy loss spectroscopy. To the best of our knowledge, the “Matryoshka doll”-like CeO2 microspheres with a facile synthesis process, low cost, and excellent microwave absorption performance are believed to be an optimal candidate of single-component absorbers and helpful in the study of absorption mechanism.
Keywords	absorption ; ceric oxide ; energy ; holography ; microparticles ; Ostwald ripening ; spectroscopy
Language	English
Dates of publication	2018-0724
Size	p. 27540-27547.
Publishing place	American Chemical Society
Document type	Article
ISSN	1944-8252
DOI	10.1021/acsami.8b10353
Database	NAL-Catalogue (AGRICOLA)

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