Calculation of Band Offsets of Mg(OH)2-Based Heterostructures

The band alignment of Mg(OH)2-based heterostructures is investigated based on first-principles calculation. (111)-MgO/(0001)-Mg(OH)2 and (0001)-wurtzite ZnO/(0001)-Mg(OH)2 heterostructures are considered. The O 2s level energy is obtained for each O atom in the heterostructure supercell, and the band edge energies are evaluated following the procedure of the core-level spectroscopy. The calculation is based on the generalized gradient approximation with the on-site Coulomb interaction parameter U considered for Zn. For MgO/Mg(OH)2, the band alignment is of type II, and the valence band edge of MgO is higher by 1.6 eV than that of Mg(OH)2. For ZnO/Mg(OH)2, the band alignment is of type I, and the valence band edge of ZnO is higher by 0.5 eV than that of Mg(OH)2. Assuming the transitivity rule, it is expected that Mg(OH)2 can be used for certain types of heterostructure solar cells and dye-sensitized solar cells to improve the performance.

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Low lying valence band edge materials based on copper oxide for tandem dye-sensitized solar cells

Materials Letters ◽

10.1016/j.matlet.2020.128151 ◽

2020 ◽

Vol 275 ◽

pp. 128151

Author(s):

Melinda Vajda ◽

Daniel Ursu ◽

Narcis Duteanu ◽

Marinela Miclau

Keyword(s):

Solar Cells ◽

Copper Oxide ◽

Valence Band ◽

Dye Sensitized Solar Cells ◽

Band Edge ◽

Valence Band Edge ◽

Dye Sensitized ◽

Sensitized Solar Cells

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Spin polarization of holes on the valence-band edge of a semiconductor quantum well

Semiconductor Science and Technology ◽

10.1088/0268-1242/13/8/004 ◽

1998 ◽

Vol 13 (8) ◽

pp. 852-857 ◽

Cited By ~ 6

Author(s):

M Z Maialle

Keyword(s):

Quantum Well ◽

Valence Band ◽

Spin Polarization ◽

Band Edge ◽

Valence Band Edge ◽

Semiconductor Quantum Well

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Determination of the valence band edge of Fe oxide nanoparticles dispersed in aqueous solution through resonant photoelectron spectroscopy from a liquid microjet

Nanoscale Advances ◽

10.1039/d1na00275a ◽

2021 ◽

Author(s):

Giorgia Olivieri ◽

Gregor Kladnik ◽

Dean Cvetko ◽

Matthew A. Brown

Keyword(s):

Aqueous Solution ◽

Electronic Structure ◽

Valence Band ◽

Photoelectron Spectroscopy ◽

Band Edge ◽

Photoemission Spectroscopy ◽

Oxide Nanoparticles ◽

Valence Band Edge ◽

Resonant Photoemission

The electronic structure of hydrated nanoparticles can be unveiled by coupling a liquid microjet with a resonant photoemission spectroscopy.

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Defects in SiC for Quantum Computing

MRS Advances ◽

10.1557/adv.2019.301 ◽

2019 ◽

Vol 4 (40) ◽

pp. 2217-2222

Author(s):

Renu Choudhary ◽

Rana Biswas ◽

Bicai Pan ◽

Durga Paudyal

Keyword(s):

Band Gap ◽

Valence Band ◽

Density Functional ◽

Single Photon ◽

Band Edge ◽

Valence Band Edge ◽

Dangling Bonds ◽

Defect Levels ◽

Formation Energies ◽

Qubit Operation

AbstractMany novel materials are being actively considered for quantum information science and for realizing high-performance qubit operation at room temperature. It is known that deep defects in wide-band gap semiconductors can have spin states and long coherence times suitable for qubit operation. We theoretically investigate from ab-initio density functional theory (DFT) that the defect states in the hexagonal silicon carbide (4H-SiC) are potential qubit materials. The DFT supercell calculations were performed with the local-orbital and pseudopotential methods including hybrid exchange-correlation functionals. Di-vacancies in SiC supercells yielded defect levels in the gap consisting of closely spaced doublet just above the valence band edge, and higher levels in the band gap. The divacancy with a spin state of 1 is charge neutral. The divacancy is characterized by C-dangling bonds and a Si-dangling bonds. Jahn-teller distortions and formation energies as a function of the Fermi level and single photon interactions with these defect levels will be discussed. In contrast, the anti-site defects where C, Si are interchanged have high formation energies of 5.4 eV and have just a single shallow defect level close to the valence band edge, with no spin. We will compare results including the defect levels from both the electronic structure approaches.

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Anion-correlated conduction band edge shifts and charge transfer kinetics in dye-sensitized solar cells with ionic liquid electrolytes

Physical Chemistry Chemical Physics ◽

10.1039/c0cp02728f ◽

2011 ◽

Vol 13 (9) ◽

pp. 3788-3794 ◽

Cited By ~ 24

Author(s):

Min Zhang ◽

Jing Zhang ◽

Yu Bai ◽

Yinghui Wang ◽

Mei Su ◽

...

Keyword(s):

Ionic Liquid ◽

Solar Cells ◽

Charge Transfer ◽

Conduction Band ◽

Dye Sensitized Solar Cells ◽

Band Edge ◽

Conduction Band Edge ◽

Dye Sensitized ◽

Liquid Electrolytes ◽

Sensitized Solar Cells

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Conduction and valence band edge properties of hexagonal InN characterized by optical measurements

physica status solidi (c) ◽

10.1002/pssc.200565386 ◽

2006 ◽

Vol 3 (6) ◽

pp. 1850-1853 ◽

Cited By ~ 18

Author(s):

Y. Ishitani ◽

W. Terashima ◽

S. B. Che ◽

A. Yoshikawa

Keyword(s):

Valence Band ◽

Optical Measurements ◽

Band Edge ◽

Valence Band Edge

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PN/PAs-WSe2 van der Waals heterostructures for solar cell and photodetector

Scientific Reports ◽

10.1038/s41598-020-73152-7 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Xinyi Zheng ◽

Yadong Wei ◽

Kaijuan Pang ◽

Ngeywo Kaner Tolbert ◽

Dalin Kong ◽

...

Keyword(s):

Refractive Index ◽

Solar Cells ◽

Negative Refractive Index ◽

Wide Spectrum ◽

Van Der Waals ◽

Band Alignment ◽

Ultraviolet Region ◽

Type I ◽

Type Ii ◽

Van Der Waals Heterostructures

Abstract By first-principles calculations, we investigate the geometric stability, electronic and optical properties of the type-II PN-WSe2 and type-I PAs-WSe2 van der Waals heterostructures(vdWH). They are p-type semiconductors with indirect band gaps of 1.09 eV and 1.08 eV based on PBE functional respectively. By applying the external gate field, the PAs-WSe2 heterostructure would transform to the type-II band alignment from the type-I. With the increasing of magnitude of the electric field, two heterostructures turn into the n-type semiconductors and eventually into metal. Especially, PN/PAs-WSe2 vdWH are both high refractive index materials at low frequencies and show negative refractive index at high frequencies. Because of the steady absorption in ultraviolet region, the PAs-WSe2 heterostructure is a highly sensitive UV detector material with wide spectrum. The type-II PN-WSe2 heterostructure possesses giant and broadband absorption in the near-infrared and visible regions, and its solar power conversion efficiency of 13.8% is higher than the reported GaTe–InSe (9.1%), MoS2/p-Si (5.23%) and organic solar cells (11.7%). It does project PN-WSe2 heterostructure a potential for application in excitons-based solar cells.

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Photocatalytic properties of a new Z-scheme system BaTiO3/In2S3 with a core–shell structure

RSC Advances ◽

10.1039/c8ra10592h ◽

2019 ◽

Vol 9 (20) ◽

pp. 11377-11384 ◽

Cited By ~ 6

Author(s):

Kaili Wei ◽

Baolai Wang ◽

Jiamin Hu ◽

Fuming Chen ◽

Qing Hao ◽

...

Keyword(s):

Charge Transfer ◽

Valence Band ◽

Conduction Band ◽

Shell Structure ◽

Band Edge ◽

Conduction Band Edge ◽

Core Shell ◽

Valence Band Edge ◽

Core Shell Structure ◽

Positive Valence

It's highly desired to design an effective Z-scheme photocatalyst with excellent charge transfer and separation, a more negative conduction band edge (ECB) than O2/·O2− (−0.33 eV) and a more positive valence band edge (EVB) than ·OH/OH− (+2.27 eV).

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