Atomic Pt and molecular H2O adsorptions on SrTiO3 with and without Nb-doping: Electron trapping center and mediating roles of Pt in charge transfer from semiconductor to water

In this paper, the electrical properties of pre- and post-rapid thermal annealed 4H SiC-based gate oxide grown in 10% nitrous oxide (N2O) and in dry oxygen have been investigated, compared, and reported for the first time. After treating the nitrided gate oxide in rapid thermal annealing (RTA), oxide breakdown characteristic has been improved significantly. This improvement has been attributed to the reduction of SiC–SiO2 interface-trap density and the generation of positive oxide charge, acting as an electron-trapping center. However, deleterious effects have been observed in non-nitrided oxide after subjected to the same RTA treatment. The differences in oxide-breakdown strength of these oxides have been explained and modeled.

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Prolonged electron lifetime in sulfur vacancy-rich ZnCdS nanocages by interstitial phosphorus doping for photocatalytic water reduction

Materials Chemistry Frontiers ◽

10.1039/d0qm00464b ◽

2020 ◽

Vol 4 (11) ◽

pp. 3234-3239

Author(s):

Qiaohong Zhu ◽

Zehong Xu ◽

Qiuying Yi ◽

Muhammad Nasir ◽

Mingyang Xing ◽

...

Keyword(s):

Fermi Level ◽

Photocatalytic Performance ◽

Electron Trapping ◽

Electron Lifetime ◽

Phosphorus Doping ◽

Sulfur Vacancy ◽

Effective Electron ◽

Dopant Atoms ◽

Vacancy Level ◽

Electron Trapping Center

Sulfur vacancy-rich ZnCdS nanocages with interstitial P dopant atoms were fabricated. The promoted Fermi level caused by interstitial P doping facilitates the S vacancy level to be an effective electron trapping center, thus enhancing the photocatalytic performance.

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Shallow and deep trap states of solvated electrons in methanol and their formation, electronic excitation, and relaxation dynamics

10.26434/chemrxiv-2021-84b7p-v2 ◽

2021 ◽

Author(s):

Jinggang Lan ◽

Yo-ichi Yamamoto ◽

Toshinori Suzuki ◽

Vladimir Rybkin

Keyword(s):

Charge Transfer ◽

Electron Trapping ◽

Electronic Transitions ◽

Methyl Groups ◽

Trap States ◽

Relaxation Dynamics ◽

Primary Alcohols ◽

Solvated Electrons ◽

Excess Electrons ◽

Trapping Sites

We present condensed-phase first-principles molecular dynamics simulations to elucidate the presence of different electron trapping sites in liquid methanol and their roles in the formation, electronic transitions, and relaxation of solvated electrons (e−met) in methanol. Excess electrons injected into liquid methanol are most likely trapped by methyl groups, but rapidly diffuse to more stable trapping sites with dangling OH bonds. After localization at the sites with one free OH bond (1OH trapping sites), reorientation of other methanol molecules increases the OH coordination number and the trap depth, and ultimately four OH bonds become coordinated with the excess electrons under thermal conditions. The simulation identified four distinct trapping states with different OH coordination numbers. The simulation results also revealed that electronic transitions of e−met are primarily due to charge transfer between electron trapping sites (cavities) formed by OH and methyl groups and that these transitions differ from hydrogenic electronic transitions involving aqueous solvated electrons (e−aq). Such charge transfer also explains the alkyl-chain-length dependence of the photoabsorption peak wavelength and the excited-state lifetime of solvated electrons in primary alcohols.

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Electronic Characterization of Dislocations in Rtcvd Germanium-Silicon/Silicon Grown by Graded Layer Epitaxy

MRS Proceedings ◽

10.1557/proc-325-159 ◽

1993 ◽

Vol 325 ◽

Cited By ~ 7

Author(s):

P.N. Grillot ◽

S.A. Ringel ◽

G.P. Watsona ◽

E.A. Fitzgerald ◽

Y.H. Xie

Keyword(s):

Peak Height ◽

Trapping Center ◽

Applied Bias ◽

Recombination Activity ◽

Hole Trapping ◽

Trapping Centers ◽

Germanium Silicon ◽

Silicon Silicon ◽

Electron Trapping Center

AbstractCarrier trapping and recombination activity have been studied with DLTS and EBIC in RTCVD grown compositionally graded Ge0.3Si0.7/Si heterostructures. DLTS peak height is found to vary with applied bias, and the bias conditions used indicate that at least one peak is present in the homoepitaxial Si buffer layer and perhaps the substrate as well. Variations in EBIC contrast as a function of reverse bias, and DLTS fill pulse experiments both indicate that the DLTS peaks observed are dislocation related. Moreover, the bias dependent decrease in DLTS peak height is observed to occur at different rates for different peaks, indicating a possible connection between certain DLTS peaks and dislocation orientation or type. Activation energies of one electron trapping center and one hole trapping center add up to roughly the expected bandgap in a relaxed GexSi1−x, alloy with x ≦ 0.3, indicating that the electron and hole trapping centers observed with DLTS may, in fact, be associated with the R-G center observed by EBIC.

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Charge transfer rates and electron trapping at buried interfaces of perovskite solar cells

Joule ◽

10.1016/j.joule.2021.07.016 ◽

2021 ◽

Author(s):

Igal Levine ◽

Amran Al-Ashouri ◽

Artem Musiienko ◽

Hannes Hempel ◽

Artiom Magomedov ◽

...

Keyword(s):

Solar Cells ◽

Charge Transfer ◽

Perovskite Solar Cells ◽

Electron Trapping ◽

Transfer Rates ◽

Buried Interfaces

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Study of charge transfer in FeTi

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075270 ◽

1983 ◽

Vol 41 ◽

pp. 296-297

Author(s):

J. Taft∅

Keyword(s):

Charge Transfer ◽

Charge Distribution ◽

Electron Scattering ◽

Periodic System ◽

Electron Distribution ◽

Scattering Amplitude ◽

Transition Elements ◽

Hartree Fock ◽

Cscl Structure ◽

The Right

It is well known that for reflections corresponding to large interplanar spacings (i.e., sin θ/λ small), the electron scattering amplitude, f, is sensitive to the ionicity and to the charge distribution around the atoms. We have used this in order to obtain information about the charge distribution in FeTi, which is a candidate for storage of hydrogen. Our goal is to study the changes in electron distribution in the presence of hydrogen, and also the ionicity of hydrogen in metals, but so far our study has been limited to pure FeTi. FeTi has the CsCl structure and thus Fe and Ti scatter with a phase difference of π into the 100-ref lections. Because Fe (Z = 26) is higher in the periodic system than Ti (Z = 22), an immediate “guess” would be that Fe has a larger scattering amplitude than Ti. However, relativistic Hartree-Fock calculations show that the opposite is the case for the 100-reflection. An explanation for this may be sought in the stronger localization of the d-electrons of the first row transition elements when moving to the right in the periodic table. The tabulated difference between fTi (100) and ffe (100) is small, however, and based on the values of the scattering amplitude for isolated atoms, the kinematical intensity of the 100-reflection is only 5.10-4 of the intensity of the 200-reflection.

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