Tuning the near-gap electronic structure of Cu2O by anion–cation co-doping for enhanced solar energy conversion

Doping is an effective strategy to tune the electronic properties of semiconductors, but some side effects caused by mono-doping degrade the specific performance of matrixes. As a model system to minimize photoproduced electron-hole pairs recombination by anion–cation co-doping, we investigate the electronic structures and optical properties of (Fe[Formula: see text]+[Formula: see text]N) co-doped Cu2O using the first-principles calculations. Compared to the case of mono-doping, the Fe[Formula: see text]N[Formula: see text] (a Fe (N) atom substituting a Cu (O) atom) co-doping reduces the energy cost of doping as a consequence of the charge compensation between the iron and nitrogen impurities, which eliminates the isolated levels (induced by mono-dopant) in the band gap. Interestingly, it is found that the contributions of different host atoms (Cu and O) away from anion (N) and cation (Fe) dopants to the variation of near band gap electronic structure of the co-doped Cu2O are different. Moreover, co-doping reduces the band gap and increases the visible-light absorption of Cu2O. Both band gap reduction and low recombination rate are critical elements for efficient light-to-current conversion in co-doped semiconductor photocatalysts. These findings raise the prospect of using co-doped Cu2O with specifically engineered electronic properties in a variety of solar applications.

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First principles study of defects in solid electrolyte lithium thiophosphate Li7P3S11

MRS Proceedings ◽

10.1557/opl.2011.1423 ◽

2011 ◽

Vol 1331 ◽

Author(s):

Ka Xiong ◽

Weichao Wang ◽

Roberto Longo Pazos ◽

Kyeongjae Cho

Keyword(s):

Electronic Structure ◽

Solid Electrolyte ◽

Band Gap ◽

Electronic Properties ◽

First Principles ◽

Wide Band ◽

Ion Conductivity ◽

First Principles Calculations ◽

Wide Band Gap ◽

Formation Energies

ABSTRACTWe investigate the electronic structure of interstitial Li and Li vacancy in Li7P3S11 by first principles calculations. We find that Li7P3S11 is a good insulator with a wide band gap of 3.5 eV. We find that the Li vacancy and interstitial Li+ ion do not introduce states in the band gap hence they do not deteriorate the electronic properties of Li7P3S11. The calculated formation energies of Li vacancies are much larger than those of Li interstitials, indicating that the ion conductivity may arise from the migration of interstitial Li.

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Atomic and electronic structure of superionic solid electrolyte Li10GeP2S12

MRS Proceedings ◽

10.1557/opl.2012.1285 ◽

2012 ◽

Vol 1440 ◽

Cited By ~ 1

Author(s):

Ka Xiong ◽

Roberto Longo Pazos ◽

Kyeongjae Cho

Keyword(s):

Electronic Structure ◽

Solid Electrolyte ◽

Band Gap ◽

Electronic Properties ◽

First Principles ◽

Energy Barrier ◽

Ion Conductivity ◽

First Principles Calculations ◽

Interstitial Diffusion ◽

Atomic And Electronic Structure

ABSTRACTWe investigate the electronic structure of interstitial Li and Li vacancy in Li10GeP2S12 by first principles calculations. We find that the Li vacancy and interstitial Li+ ion do not introduce states in the band gap hence they do not deteriorate the electronic properties of Li10GeP2S12. The energy barrier for Li interstitial diffusion in Li10GeP2S12 is estimated to be 1.4 eV, which is much larger than that of the Li vacancy in Li10GeP2S12. This fact suggests that the ion conductivity arises from the migration of Li vacancy.

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Electronic structure engineering of tin telluride through co-doping of bismuth and indium for high performance thermoelectrics: a synergistic effect leading to a record high room temperature ZT in tin telluride

Journal of Materials Chemistry C ◽

10.1039/c9tc01184f ◽

2019 ◽

Vol 7 (16) ◽

pp. 4817-4821 ◽

Cited By ~ 19

Author(s):

U. Sandhya Shenoy ◽

D. Krishna Bhat

Keyword(s):

Electronic Structure ◽

Synergistic Effect ◽

Band Gap ◽

High Performance ◽

Room Temperature ◽

Band Offset ◽

Valence Band Offset ◽

Co Doping ◽

Tin Telluride ◽

Structure Engineering

Resonance states due to Bi and In co-doping, band gap enlargement, and a reduced valence-band offset in SnTe lead to a record high room-temperature ZT.

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Strain-induced semimetal-to-semiconductor transition and indirect-to-direct band gap transition in monolayer 1T-TiS2

RSC Advances ◽

10.1039/c5ra16877e ◽

2015 ◽

Vol 5 (102) ◽

pp. 83876-83879 ◽

Cited By ~ 23

Author(s):

Chengyong Xu ◽

Paul A. Brown ◽

Kevin L. Shuford

Keyword(s):

Band Gap ◽

Electronic Properties ◽

Plane Strain ◽

Material Properties ◽

First Principles ◽

Tensile Strain ◽

First Principles Calculations ◽

Direct Band Gap ◽

Direct Band ◽

Uniform Plane

We have investigated the effect of uniform plane strain on the electronic properties of monolayer 1T-TiS2using first-principles calculations. With the appropriate tensile strain, the material properties can be transformed from a semimetal to a direct band gap semiconductor.

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First-Principles Study on the Stabilities, Electronic and Optical Properties of GexSn1-xSe Alloys

Nanomaterials ◽

10.3390/nano8110876 ◽

2018 ◽

Vol 8 (11) ◽

pp. 876 ◽

Cited By ~ 1

Author(s):

Qi Qian ◽

Lei Peng ◽

Yu Cui ◽

Liping Sun ◽

Jinyan Du ◽

...

Keyword(s):

Optical Properties ◽

Solar Cells ◽

Band Gap ◽

Electronic Properties ◽

First Principles ◽

Future Application ◽

First Principles Calculations ◽

Electronic And Optical Properties ◽

Direct Bandgap ◽

The Future

We systematically study, by using first-principles calculations, stabilities, electronic properties, and optical properties of GexSn1-xSe alloy made of SnSe and GeSe monolayers with different Ge concentrations x = 0.0, 0.25, 0.5, 0.75, and 1.0. Our results show that the critical solubility temperature of the alloy is around 580 K. With the increase of Ge concentration, band gap of the alloy increases nonlinearly and ranges from 0.92 to 1.13 eV at the PBE level and 1.39 to 1.59 eV at the HSE06 level. When the Ge concentration x is more than 0.5, the alloy changes into a direct bandgap semiconductor; the band gap ranges from 1.06 to 1.13 eV at the PBE level and 1.50 to 1.59 eV at the HSE06 level, which falls within the range of the optimum band gap for solar cells. Further optical calculations verify that, through alloying, the optical properties can be improved by subtle controlling the compositions. Since GexSn1-xSe alloys with different compositions have been successfully fabricated in experiments, we hope these insights will contribute to the future application in optoelectronics.

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CHANGES INDUCED IN THE SURFACE ELECTRONIC STRUCTURE OF Be(0001) AFTER Si ADSORPTION

Surface Review and Letters ◽

10.1142/s0218625x02002907 ◽

2002 ◽

Vol 09 (02) ◽

pp. 687-691

Author(s):

L. I. JOHANSSON ◽

C. VIROJANADARA ◽

T. BALASUBRAMANIAN

Keyword(s):

Electronic Structure ◽

Band Structure ◽

Band Gap ◽

Electronic Properties ◽

Surface State ◽

Core Level ◽

Clean Surface ◽

Core Level Spectrum ◽

Surface Band ◽

Surface Electronic Structure

A study of effects induced in the Be 1s core level spectrum and in the surface band structure after Si adsorption on Be(0001) is reported. The changes in the Be 1s spectrum are quite dramatic. The number of resolvable surface components and the magnitude of the shifts do decrease and the relative intensities of the shifted components are drastically different compared to the clean surface. The surface band structure is also strongly affected after Si adsorption and annealing. At [Formula: see text] the surface state is found to move down from 2.8 to 4.1 eV. The band also splits at around 0.5 Å-1 along both the [Formula: see text] and [Formula: see text] directions. At [Formula: see text] and beyond [Formula: see text] only one surface state is observed in the band gap instead of the two for the clean surface. Our findings indicate that a fairly small amount of Si in the outer atomic layers strongly modifies the electronic properties of these layers.

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Band gap and morphology engineering of TiO2 by silica and fluorine co-doping for efficient ultraviolet and visible photocatalysis

RSC Advances ◽

10.1039/c6ra06410h ◽

2016 ◽

Vol 6 (68) ◽

pp. 63117-63130 ◽

Cited By ~ 21

Author(s):

Hua Tang ◽

Shufang Chang ◽

Kongqiang Wu ◽

Guogang Tang ◽

Yanhui Fu ◽

...

Keyword(s):

Photocatalytic Activity ◽

Band Gap ◽

Synthetic Method ◽

Co Doping ◽

Morphology Engineering ◽

Visible Photocatalysis ◽

Co Doped

Silicon and fluorine co-doped anatase TiO2 (Si–F–TiO2) photocatalysts with enhanced photocatalytic activity were successfully prepared via a facile two-step synthetic method by using SiO2 powders and (NH4)2TiF6 as the precursors.

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Structure and electronic properties of C2N/graphene predicted by first-principles calculations

RSC Advances ◽

10.1039/c5ra26873g ◽

2016 ◽

Vol 6 (34) ◽

pp. 28484-28488 ◽

Cited By ~ 25

Author(s):

Dandan Wang ◽

DongXue Han ◽

Lei Liu ◽

Li Niu

Keyword(s):

Band Gap ◽

Electronic Properties ◽

Water Splitting ◽

First Principles ◽

First Principles Calculations ◽

Gap Opening

Graphene band gap opening is achieved when integrated with C2N. C2N/graphene heterostructures are promising materials for FETs and water splitting.

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COMPARATIVE STUDY OF THE STRUCTURAL AND ELECTRONIC PROPERTIES OF BN(5, 5) AND C(5, 5) NANOTUBES UNDER PRESSURE

International Journal of Modern Physics B ◽

10.1142/s0217979210056876 ◽

2010 ◽

Vol 24 (24) ◽

pp. 4851-4859

Author(s):

KAIHUA HE ◽

GUANG ZHENG ◽

GANG CHEN ◽

QILI CHEN ◽

MIAO WAN ◽

...

Keyword(s):

High Pressure ◽

Comparative Study ◽

Charge Density ◽

Band Gap ◽

Electronic Properties ◽

Cross Section ◽

First Principles ◽

First Principles Calculations ◽

Zinc Blende ◽

Structural And Electronic Properties

The structural and electronic properties of BN(5, 5) and C(5, 5) nanotubes under pressure are studied by using first principles calculations. In our study range, BN(5, 5) undergoes obvious elliptical distortion, while for C(5, 5) the cross section first becomes an ellipse and then, under further pressure, is flattened. The band gap of BN(5, 5) decreases with increasing pressure, which is inverse to that of zinc blende BN, whereas for C(5, 5) the metallicity is always preserved under high pressure. The population of charge density indicates that intertube bonding is formed under pressure. We also find that BN(5, 5) may collapse, and a new polymer material based on C(5, 5) is formed by applying pressure.

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