Type conductivity conversion in p-CdxHg1-xTe

2003 ◽  
Author(s):  
Nicolas N. Berchenko ◽  
V. V. Bogoboyashchyy ◽  
Igor I. Izhnin ◽  
Kurban R. Kurbanov ◽  
Andrii P. Vlasov ◽  
...  
Keyword(s):  
Type Conductivity

scholarly journals Structural, Electronic, and Optical Properties of Group 6 Doped Anatase TiO2: A Theoretical Approach

2021 ◽  
Vol 11 (4) ◽  
pp. 1657
Author(s):  
Petros-Panagis Filippatos ◽  
Nikolaos Kelaidis ◽  
Maria Vasilopoulou ◽  
Dimitris Davazoglou ◽  
Alexander Chroneos
Keyword(s):  
Optical Properties ◽  
Solar Cells ◽  
Electron Transport ◽  
Density Functional ◽  
Perovskite Solar Cells ◽  
Solar Spectrum ◽  
Type Conductivity ◽  
Electronic And Optical Properties ◽  
Group 6 ◽  
Visible Wavelengths

Titania (TiO2) is a key material used as an electron transport in dye-sensitized and halide perovskite solar cells due to its intrinsic n-type conductivity, visible transparency, low-toxicity, and abundance. Moreover, it exhibits pronounced photocatalytic properties in the ultra-violet part of the solar spectrum. However, its wide bandgap (around 3.2 eV) reduces its photocatalytic activity in the visible wavelengths’ region and electron transport ability. One of the most efficient strategies to simultaneously decrease its bandgap value and increase its n-type conductivity is doping with appropriate elements. Here, we have investigated using the density functional theory (DFT), as well as the influence of chromium (Cr), molybdenum (Mo), and tungsten (W) doping on the structural, electronic, and optical properties of TiO2. We find that doping with group 6 elements positively impacts the above-mentioned properties and should be considered an appropriate method for photocatalystic applications. In addition to the pronounced reduction in the bandgap values, we also predict the formation of energy states inside the forbidden gap, in all the cases. These states are highly desirable for photocatalytic applications as they induce low energy transitions, thus increasing the oxide’s absorption within the visible. Still, they can be detrimental to solar cells’ performance, as they constitute trap sites for photogenerated charge carriers.

Achieving p-type conductivity in wide-bandgap SnO2 by a two-step process

2021 ◽  
Vol 118 (11) ◽  
pp. 112102
Author(s):  
Wang Fu ◽  
Mingkai Li ◽  
Jiashuai Li ◽  
Guojia Fang ◽  
Pan Ye ◽  
...  
Keyword(s):  
Wide Bandgap ◽  
Step Process ◽  
Type Conductivity ◽  
P Type

scholarly journals Effect of Mn2+ substitution on the structure, properties and HER activity of cadmium phosphochlorides

RSC Advances ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 5134-5145
Author(s):  
Anand Roy ◽  
Anjali Singh ◽  
S. Assa Aravindh ◽  
Swaraj Servottam ◽  
Umesh V. Waghmare ◽  
...  
Keyword(s):  
Type Conductivity ◽  
P Type ◽  
Structure Properties

Mn2+ prefers the Cd-sites having larger number of tightly bounded Cl-ligands. Pure Cd7P4Cl6 exhibits n-type conductivity whereas Cd5.8Mn1.2P4Cl6 exhibits p-type conductivity. The HER activity of Cd7−yMnyP4Cl6 is superior to that of pristine Cd7P4Cl6.

Enhanced n‐type conductivity of 6H‐SiC nanowires by nitrogen doping

2019 ◽  
Vol 14 (9) ◽  
pp. 999-1002
Author(s):  
Shanying Li ◽  
Jie Li ◽  
Qing Su ◽  
Xiangyun Liu ◽  
Haipeng Zhao ◽  
...  
Keyword(s):  
Nitrogen Doping ◽  
Type Conductivity ◽  
Sic Nanowires

p-type conductivity in silicon nanowires induced by heterojunction interface charge transfer

2010 ◽  
Vol 97 (15) ◽  
pp. 153126 ◽  
Author(s):  
G. D. Yuan ◽  
T. W. Ng ◽  
Y. B. Zhou ◽  
F. Wang ◽  
W. J. Zhang ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Silicon Nanowires ◽  
Type Conductivity ◽  
Interface Charge ◽  
P Type ◽  
Interface Charge Transfer

Preparation and Properties of CdTe Films on Mo/Glass Substrates

2009 ◽  
Vol 1165 ◽  
Author(s):  
Vello Valdna ◽  
Maarja Grossberg ◽  
Hiie Jaan ◽  
Urve Kallavus ◽  
Valdek Mikli ◽  
...  
Keyword(s):  
Cadmium Chloride ◽  
Radiation Detectors ◽  
Cdte Film ◽  
Chloride Flux ◽  
Type Conductivity ◽  
Coated Glass ◽  
Glass Substrates ◽  
Group I ◽  
Cdte Films ◽  
P Type

AbstractShort-bandgap group II-VI compound cadmium telluride is widely used for the infrared optics, radiation detectors, and solar cells where p-type CdTe is needed. p-type conductivity of CdTe is mainly caused by the chlorine-based A-centers, and in part, by the less stable copper-oxygen complexes. As a rule, CdTe films are recrystallized by the help of a cadmium chloride flux that saturates CdTe with chlorine. In chlorine-saturated CdTe A-centers are converted to isoelectronic complexes that cause resistivity increasement of CdTe up to 9 orders of magnitude. Excess copper and oxygen or group I elements as sodium also deteriorate the p-type conductivity of CdTe like excess chlorine. p-type conductivity of CdTe can be restored e.g. by the vacuum annealing which removes excess chlorine from the film. Unfortunately, treatment that betters p-type conductivity of the CdTe film degrades the junction of the superstrate configuration cells. In this work we investigate possibilities to prepare p-type CdTe films on the molybdenum coated glass substrates. Samples were prepared by the vacuum evaporation and dynamic recrystallization of 6N purity CdTe on the top of Mo-coated glass substrates. Then samples were recrystallized with cadmium chloride flux under tellurium vapour pressure. Results of the test studies on the structure and electronic parameters of samples are presented and discussed.

Investigation of the Hydrogen Transport Processes in Crystalline Silicon of n-Type Conductivity

2007 ◽  
Vol 131-133 ◽  
pp. 425-430 ◽  
Author(s):  
Anis M. Saad ◽  
Oleg Velichko ◽  
Yu P. Shaman ◽  
Adam Barcz ◽  
Andrzej Misiuk ◽  
...  
Keyword(s):  
Hydrogen Concentration ◽  
Room Temperature ◽  
Crystalline Silicon ◽  
Transport Processes ◽  
Concentration Profiles ◽  
Hydrogen Transport ◽  
Hydrogen Atoms ◽  
Near Surface ◽  
Type Conductivity ◽  
Hydrogen Molecules

The silicon substrates were hydrogenated at approximately room temperature and hydrogen concentration profiles vs. depth have been measured by SIMS. Czochralski grown (CZ) wafers, both n- and p-type conductivity, were used in the experiments under consideration. For analysis of hydrogen transport processes and quasichemical reactions the model of hydrogen atoms diffusion and quasichemical reactions is proposed and the set of equations is obtained. The developed model takes into account the formation of bound hydrogen in the near surface region, hydrogen transport as a result of diffusion of hydrogen molecules 2 H , diffusion of metastable complexes * 2 H and diffusion of nonequilibrium hydrogen atoms. Interaction of 2 H with oxygen atoms and formation of immobile complexes “oxygen atom - hydrogen molecule” (O - H2 ) is also taken into account to explain the hydrogen concentration profiles in the substrates of n-type conductivity. The computer simulation based on the proposed equations has shown a good agreement of the calculated hydrogen profiles with the experimental data and has allowed receiving a value of the hydrogen molecules diffusivity at room temperature.

First-Principles Study on the Conductive Properties of P-Doped ZnO

2009 ◽  
Vol 79-82 ◽  
pp. 1253-1256 ◽  
Author(s):  
Li Guan ◽  
Qiang Li ◽  
Xu Li ◽  
Jian Xin Guo ◽  
Bo Geng ◽  
...  
Keyword(s):  
Fermi Level ◽  
Valence Band ◽  
Density Functional ◽  
Lattice Structure ◽  
Mulliken Charge ◽  
Total Density ◽  
Type Conductivity ◽  
Doped Zno ◽  
P Type ◽  
Conductive Properties

In the present paper, the lattice structure, band structure and density of state of pure and P-doped ZnO are calculated by first-principle method based on density functional theory. By analyzing the Mulliken charge overlap population and bond length, it is found that the bond of P-Zn is longer and stronger than O-Zn bond for PO-ZnO. But for PZn-ZnO, the O-P bond becomes shorter and more powerful than O-Zn bond. Also, weak O-O bonds are formed in this case. Our results show that the final total energy of PO-ZnO is lower than PZn-ZnO. The lattice structure of PO-ZnO is more stability than PZn-ZnO. For PO-ZnO, The Fermi level moves into the valence band, which expresses that the holes appear on the top of valence band and thus the PO-ZnO exhibits p-type conductivity. For PZn-ZnO, the Fermi level moves up to the conductor band and the total density of states shifts to the lower energy region, thus PZn-ZnO shows the n-type conductivity.

Sign in / Sign up

Export Citation Format

Share Document