Trapping of injected minority carriers by redox reagents in the dark and fermi level unpinning at the n-MoSe2/electrolyte interface

Modification of several semiconductors material surfaces with H4SiW12O40•nH2O have been carried out to produce an increase in the open circuit photopotential at the semiconductor/electrolyte interface (Voc) without changing the flat-band potential. The augmentation of Voc is shown to be attributed to a decrease of the minority carriers recombination at the semiconductor/electrolyte interface along with the suppression of Fermi level pinning. The enhancement of Voc and the electrocatalytic activity of the hydrogen evolution reaction in acidic medium of the derivatized electrodes is attributed to the Fermi level unpinning. Keywords: photoelectrodes, photoelectrocatalysis, pinning, modification improvement.

Download Full-text

A DSSC with an Efficiency of ∼10 %: Fermi Level Manipulation Impacting the Electron Transport at the Photoelectrode-Electrolyte Interface

ChemistrySelect ◽

10.1002/slct.201601461 ◽

2016 ◽

Vol 1 (19) ◽

pp. 6179-6187 ◽

Cited By ~ 3

Author(s):

Suman Kushwaha ◽

Sudip Mandal ◽

Sundar Subramanian ◽

Subrahmanyam Aryasomayajul ◽

Kothandaraman Ramanujam

Keyword(s):

Electron Transport ◽

Fermi Level ◽

Electrolyte Interface

Download Full-text

Hydrogen-Related Donors in Silicon: Centers with Negative Electronic Correlation Energy

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.108-109.229 ◽

2005 ◽

Vol 108-109 ◽

pp. 229-234 ◽

Cited By ~ 1

Author(s):

Yurii M. Pokotilo ◽

Alla N. Petukh ◽

Valentin V. Litvinov ◽

B.G. Tsvirko

Keyword(s):

Fermi Level ◽

Room Temperature ◽

Correlation Energy ◽

Electronic Correlation ◽

Equilibrium Configurations ◽

Double Electron ◽

Related Donor ◽

Minority Carriers ◽

Double Hydrogen ◽

Electron Occupation

The transformation of the shallow hydrogen-related donors, which have been formed in the silicon samples by irradiation of the low energy (300 keV) protons and following heat treatment under 350 0С or 450 0С was investigated. The experiment was carried out on Ag-Mo-Si Shottky diodes and diodes with shallow p+-n-junction. The concentration and distribution of these donors were defined by C-V-method at 1.2 MHz frequency. Using temperature dependence of equilibrium electron concentration it was established, that the hydrogen-related donors were charged controlled centers with negative electronic correlation energy (U<0). The transformation between both equilibrium configurations of the double hydrogen-related donor takes place when value of the Fermi level is arranged near Ec-0.30 eV. It was revealed that the donor transformation from neutral into double charged state have been stimulated by minority carriers trapping under room temperature when Fermi level was higher then level of the double electron occupation E(0/++)= Ec-0.30 eV.

Download Full-text

Defect quasi Fermi level control-based CN reduction in GaN: Evidence for the role of minority carriers

Applied Physics Letters ◽

10.1063/1.5000720 ◽

2017 ◽

Vol 111 (15) ◽

pp. 152101 ◽

Cited By ~ 9

Author(s):

Pramod Reddy ◽

Felix Kaess ◽

James Tweedie ◽

Ronny Kirste ◽

Seiji Mita ◽

...

Keyword(s):

Fermi Level ◽

Level Control ◽

Quasi Fermi Level ◽

Minority Carriers

Download Full-text

A quantitative study of Fermi level pinning at a semiconductor-electrolyte interface

Journal of Electroanalytical Chemistry ◽

10.1016/s0022-0728(80)80455-4 ◽

1980 ◽

Vol 114 (2) ◽

pp. 299-303 ◽

Cited By ~ 23

Author(s):

J.-N. Chazalviel ◽

T.B. Truong

Keyword(s):

Fermi Level ◽

Quantitative Study ◽

Fermi Level Pinning ◽

Electrolyte Interface

Download Full-text

Polymorphous Silicon: Transport Properties and Solar Cell Applications

MRS Proceedings ◽

10.1557/proc-557-501 ◽

1999 ◽

Vol 557 ◽

Cited By ~ 21

Author(s):

C. Longeaud ◽

J. P. Kleider ◽

M. Gauthier ◽

R. Brtiggemann ◽

Y. Poissant ◽

...

Keyword(s):

Fermi Level ◽

Transport Properties ◽

Density Of States ◽

Diffusion Length ◽

Hydrogenated Amorphous Silicon ◽

Capacitance Measurements ◽

New Material ◽

Hydrogenated Amorphous ◽

Minority Carriers ◽

Excellent Stability

AbstractTransport properties of hydrogenated polymorphous silicon layers (pm-Si:H) deposited at 150°C under various pressures in the range 80-293 Pa in sandwich (Schottky and p-i-n diodes) and coplanar structures have been compared to those of hydrogenated amorphous silicon (a-Si:H) samples deposited at the same temperature in standard conditions. The layers have been studied as-deposited, annealed and after light-soaking. With increasing pressure up to 240 Pa: i) the density of states above the Fermi level decreases as determined by means of the modulated photocurrent technique, ii) the mobility-lifetime products of electrons and holes measured by means of steady-state photoconductivity and photocarrier grating techniques both increase. The highest values for the diffusion length of minority carriers exceed 200 nm. Capacitance measurements as a function of frequency and temperature show that the density of states at the Fermi level is lower in the pm-Si:H than in the a-Si:H films. After light-soaking the diffusion length of minority carriers in a-Si:H is reduced by a factor oftwo whereas it is less reduced or not affected in the pm-Si:H layers. Solar cells including this new material present an excellent stability.

Download Full-text