Author
Wai-Ning Mei
Other affiliations: University of Nebraska–Lincoln, ASTRON, University at Buffalo
Bio: Wai-Ning Mei is an academic researcher from University of Nebraska Omaha. The author has contributed to research in topics: Band gap & Dielectric. The author has an hindex of 37, co-authored 165 publications receiving 5668 citations. Previous affiliations of Wai-Ning Mei include University of Nebraska–Lincoln & ASTRON.
Papers published on a yearly basis
Papers
More filters
467 citations
TL;DR: A different approach to enhance the catalytic activity of cerium oxide nanostructures through engineering high density of oxygen vacancy defects in these catalysts without dopants is reported.
Abstract: Traditional nanostructured design of cerium oxide catalysts typically focuses on their shape, size, and elemental composition We report a different approach to enhance the catalytic activity of cerium oxide nanostructures through engineering high density of oxygen vacancy defects in these catalysts without dopants The defect engineering was accomplished by a low pressure thermal activation process that exploits the nanosize effect of decreased oxygen storage capacity in nanostructured cerium oxides
310 citations
TL;DR: In this paper, the electronic structure and optical properties of the recently synthesized stable two-dimensional carbon allotrope graphdiyne based on first-principles calculations and experimental optical spectrum were reported.
Abstract: We report the electronic structure and optical properties of the recently synthesized stable two-dimensional carbon allotrope graphdiyne based on first-principles calculations and experimental optical spectrum. Due to the enhanced Coulomb interaction in reduced dimensionality, the band gap of graphdiyne increases to 1.10 eV within the $GW$ many-body theory from a value of 0.44 eV within the density functional theory. The optical absorption is dominated by excitonic effects with a remarkable electron-hole binding energy of over 0.55 eV within the $GW$--Bethe-Salpeter equation calculation. Experimental optical absorption of graphdiyne films is performed, and comparison with the theoretical calculations is analyzed in detail.
297 citations
TL;DR: In this article, the frequency and temperature dependences of permittivity and impedance of the compounds ACu3Ti4O12 (A=Ca,Bi2∕3, Y2√3, La2 √3) in the ranges of 10−1-106Hz and −150-200°C were studied.
Abstract: We have studied the frequency and temperature dependences of permittivity and impedance of the compounds ACu3Ti4O12 (A=Ca,Bi2∕3,Y2∕3,La2∕3) in the ranges of 10−1–106Hz and −150–200°C. All compounds investigated display similar dielectric properties. Specifically, they all have a Debye-like relaxation and their dielectric constants are independent of frequency and temperature over a wide range. They all have two electrical responses in impedance formalism, indicating that there are two distinct contributions. We attribute them to grains and grain boundaries in the ceramic samples and explain the dielectric behaviors by Maxwell-Wagner relaxation arising at the interfaces between grains and their boundaries.
286 citations
TL;DR: Frequency and temperature dependences of dielectric permittivity and electric modulus of pure and Ba-doped Bi2Ti4O11 were studied in the ranges of 10−1-106'Hz and −150-350'°C, respectively as discussed by the authors.
Abstract: Frequency and temperature dependences of dielectric permittivity and electric modulus of pure and Ba-doped Bi2Ti4O11 were studied in the ranges of 10−1–106 Hz and −150–350 °C, respectively We found that the antiferroelectric phase transition temperature of Bi2Ti4O11 decreases with Ba doping In the permittivity studies, we also observed dielectric relaxation peaks shift to higher temperature with increasing frequency Furthermore, in the electric modulus formalism, conducting peaks were uncovered above 150 °C in addition to the dielectric relaxation peak We discussed the mechanisms for the dielectric relaxation and conduction processes based on TiO6 octahedra distortion and a space-charge model
235 citations
Cited by
More filters
[...]
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.
Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …
33,785 citations
Journal Article•
28,685 citations
TL;DR: In this article, a review of mostly recent activities can be found, with a brief summary of the historical perspective of the multiferroic magnetoelectric composites since its appearance in 1972.
Abstract: Multiferroic magnetoelectric materials, which simultaneously exhibit ferroelectricity and ferromagnetism, have recently stimulated a sharply increasing number of research activities for their scientific interest and significant technological promise in the novel multifunctional devices. Natural multiferroic single-phase compounds are rare, and their magnetoelectric responses are either relatively weak or occurs at temperatures too low for practical applications. In contrast, multiferroic composites, which incorporate both ferroelectric and ferri-/ferromagnetic phases, typically yield giant magnetoelectric coupling response above room temperature, which makes them ready for technological applications. This review of mostly recent activities begins with a brief summary of the historical perspective of the multiferroic magnetoelectric composites since its appearance in 1972. In such composites the magnetoelectric effect is generated as a product property of a magnetostrictive and a piezoelectric substance. A...
3,288 citations
TL;DR: A review of electronic devices based on two-dimensional materials, outlining their potential as a technological option beyond scaled complementary metal-oxide-semiconductor switches and the performance limits and advantages, when exploited for both digital and analog applications.
Abstract: The compelling demand for higher performance and lower power consumption in electronic systems is the main driving force of the electronics industry's quest for devices and/or architectures based on new materials. Here, we provide a review of electronic devices based on two-dimensional materials, outlining their potential as a technological option beyond scaled complementary metal-oxide-semiconductor switches. We focus on the performance limits and advantages of these materials and associated technologies, when exploited for both digital and analog applications, focusing on the main figures of merit needed to meet industry requirements. We also discuss the use of two-dimensional materials as an enabling factor for flexible electronics and provide our perspectives on future developments.
2,531 citations
TL;DR: The synthesis, characterization, properties, and applications of graphene-based materials are discussed and the promising properties together with the ease of processibility and functionalization make graphene- based materials ideal candidates for incorporation into a variety of functional materials.
Abstract: Graphene, a two-dimensional, single-layer sheet of sp(2) hybridized carbon atoms, has attracted tremendous attention and research interest, owing to its exceptional physical properties, such as high electronic conductivity, good thermal stability, and excellent mechanical strength. Other forms of graphene-related materials, including graphene oxide, reduced graphene oxide, and exfoliated graphite, have been reliably produced in large scale. The promising properties together with the ease of processibility and functionalization make graphene-based materials ideal candidates for incorporation into a variety of functional materials. Importantly, graphene and its derivatives have been explored in a wide range of applications, such as electronic and photonic devices, clean energy, and sensors. In this review, after a general introduction to graphene and its derivatives, the synthesis, characterization, properties, and applications of graphene-based materials are discussed.
2,246 citations