scholarly journals Improvement of Photoelectrochemical Properties of WO3 Photoelectrode Fabricated by Using H2O2 Additive

2021 ◽  
Vol 59 (3) ◽  
pp. 177-186
Author(s):  
Seung-Hwan Jeon ◽  
Hyunjin Jeong ◽  
Seongchan Bae ◽  
Hyukhyun Ryu ◽  
Won-Jae Lee
Keyword(s):  
Current Density ◽  
Dark Current ◽  
Photocurrent Density ◽  
Flat Band ◽  
Photoelectrochemical Properties ◽  
Dark Current Density ◽  
Potential Donor ◽  
Large Influence ◽  
Vis Spectroscopy ◽  
Coating Method

In this study, we deposited a WO3 thin-film photoelectrode on a fluorine-doped tin oxide (FTO) substrate using a spin-coating method, and we investigated the photocurrent density and dark current density of the WO3 photoelectrode with various amounts of H2O2 additive. The morphological, structural, optical, electrical and photoelectrochemical properties of the WO3 photoelectrode with various amounts of H2O2 additive were analyzed using FE-SEM, XRD, UV-vis spectroscopy, EIS and a three-electrode potentiostat/galvanostat system, respectively. The amount of H2O2 additive has a large influence on the thickness of the WO3 photoelectrode, XRD (100) peak intensity, light absorption, optical energy bandgap, flat-band potential, donor density value, etc., and thus has a large influence on photoelectrochemical properties. Specifically, the H2O2 additive had a large influence on the growth of the WO3 photoelectrode, and the photocurrent density and dark current density characteristics of the WO3 photoelectrode grown to a uniform and thick thickness were largely improved. As a result, the WO3 photoelectrode fabricated with 0.2 mL of added H2O2 exhibited a high photocurrent density value of 1.17 mA/cm<sup>2</sup>, which was about 23 times higher than that of the WO3 photoelectrode fabricated without H2O2 additive, and had a dark current density value of a low 0.04 mA/cm<sup>2</sup>, which was a reduction of about 87%.

scholarly journals Effect of Annealing and of Effect of Annealing and of Cooling Rates onn-GaAs Electrode Photoelectrochemical Characteristics

2004 ◽  
Vol 27 (2) ◽  
pp. 69-80 ◽  
Author(s):  
Hikmat S. Hilal ◽  
Subhi K. Salih ◽  
Iyad A. Sa'adeddin ◽  
Guy Campet
Keyword(s):  
Current Density ◽  
Dark Current ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Photocurrent Density ◽  
Dark Current Density ◽  
Cooling Rates ◽  
Cell Efficiency ◽  
Current Densities ◽  
Rate Of Cooling

The effect of annealing of then-GaAs semiconductor on its characteristics in photoelectrochemical (PEC) systems has been investigated. The photocurrent densitiesvspotential plots were improved by annealing. Cell efficiency and short-circuit current densities were enhanced for the annealedn-GaAs.The effect of the rate of cooling of heatedn-GaAs wafers was also investigated. It was found that the slowly cooled electrodes gave better dark current densityvs. potential plots, for samples annealed below 600ºC. For samples annealed at higher temperatures, quenching gave better dark-current densityvspotential plots. Forn-GaAs, slowly cooled electrodes from temperatures below 600ºC showed better photocurrent densityvspotential plots and higher efficiency.n-GaAs samples, quenched from temperatures above 700ºC, showed better photocurrent densityvspotential plots and higher efficiency than their slowly cooled counterparts.

scholarly journals Effects of Growth Temperature on the Physicochemical and Photoelectrochemical Properties of a Modified Chemical Bath Deposited Fe2O3 Photoelectrode

2020 ◽  
Vol 58 (4) ◽  
pp. 263-271
Author(s):  
Yaejin Hong ◽  
Seung-Hwan Jeon ◽  
Hyukhyun Ryu ◽  
Won-Jae Lee
Keyword(s):  
Thin Film ◽  
Film Thickness ◽  
Growth Temperature ◽  
Electrochemical Impedance ◽  
Ph Value ◽  
Saturated Calomel Electrode ◽  
Precursor Solution ◽  
Photocurrent Density ◽  
Flat Band ◽  
Photoelectrochemical Properties

In this study, Fe2O3 photoelectrode thin films were grown on fluorine-doped tin oxide substrates at various temperatures ranging from 145 to 220 oC using modified chemical bath deposition. The morphological, structural, electrical, and photoelectrochemical properties of the resulting Fe2O3 photoelectrode were analyzed using field emission scanning electron microscopy, X-ray diffraction, electrochemical impedance spectroscopy, and a three-electrode potentiostat/galvanostat, respectively. Growth temperature and hydrochloric acid etching both affected the growth of the Fe2O3 photoelectrode, with Fe2O3 thin film thickness first increasing and then decreasing as growth temperature increased. The pH value of the precursor solution varied according to growth temperature, which in turn affected film thickness. The highest photocurrent density (0.53 mA/cm2 at 0.5 V vs. saturated calomel electrode) was obtained from the Fe2O3 photoelectrode grown at 190 oC, which yielded the thickest thin film, smallest full width at half maximum and largest grain size for the (104) and (110) plane, and highest flat-band potential value. Based on these findings, the photoelectrochemical properties of Fe2O3 photoelectrodes grown at various temperatures are strongly affected by their morphological, structural, and electrical properties.

Short-wave infrared detector with double barrier structure and low dark current density

2016 ◽  
Vol 14 (2) ◽  
pp. 022501-22505
Author(s):  
Yu Dong Yu Dong ◽  
Guanglong Wang Guanglong Wang ◽  
Haiqiao Ni Haiqiao Ni ◽  
Kangming Pei Kangming Pei ◽  
Zhongtao Qiao Zhongtao Qiao ◽  
...  
Keyword(s):  
Current Density ◽  
Dark Current ◽  
Infrared Detector ◽  
Short Wave ◽  
Barrier Structure ◽  
Dark Current Density ◽  
Double Barrier ◽  
Short Wave Infrared ◽  
Double Barrier Structure

scholarly journals Structural, Optical and Electrical Characterizations of Midwave Infrared Ga-Free Type-II InAs/InAsSb Superlattice Barrier Photodetector

Photonics ◽  
2020 ◽  
Vol 7 (3) ◽  
pp. 76
Author(s):  
U. Zavala-Moran ◽  
M. Bouschet ◽  
J. Perez ◽  
R. Alchaar ◽  
S. Bernhardt ◽  
...  
Keyword(s):  
Current Density ◽  
Dark Current ◽  
Spectral Response ◽  
Minority Carrier Lifetime ◽  
Peak Position ◽  
Type Ii ◽  
Dark Current Density ◽  
Time Resolved ◽  
Midwave Infrared ◽  
Electrical Characterizations

In this paper, a full set of structural, optical and electrical characterizations performed on midwave infrared barrier detectors based on a Ga-free InAs/InAsSb type-II superlattice, grown by molecular beam epitaxy (MBE) on a GaSb substrate, are reported and analyzed. a Minority carrier lifetime value equal to 1 µs at 80 K, carried out on dedicated structure showing photoluminescence peak position at 4.9 µm, is extracted from a time resolved photoluminescence measurement. Dark current density as low as 3.2 × 10−5 A/cm2 at 150 K is reported on the corresponding device exhibiting a 50% cut-off wavelength around 5 µm. A performance analysis through normalized spectral response and dark current density-voltage characteristics was performed to determine both the operating bias and the different dark current regimes.

scholarly journals Demonstration of Planar Type-II Superlattice-Based Photodetectors Using Silicon Ion-Implantation

Photonics ◽  
2020 ◽  
Vol 7 (3) ◽  
pp. 68
Author(s):  
Arash Dehzangi ◽  
Donghai Wu ◽  
Ryan McClintock ◽  
Jiakai Li ◽  
Alexander Jaud ◽  
...  
Keyword(s):  
Ion Implantation ◽  
Quantum Efficiency ◽  
Current Density ◽  
Dark Current ◽  
Infrared Photodetectors ◽  
Type Ii ◽  
Dark Current Density ◽  
Applied Bias ◽  
Type Ii Superlattice ◽  
Specific Detectivity

In this letter, we report the demonstration of a pBn planar mid-wavelength infrared photodetectors based on type-II InAs/InAs1−xSbx superlattices, using silicon ion-implantation to isolate the devices. At 77 K the photodetectors exhibited peak responsivity of 0.76 A/W at 3.8 µm, corresponding to a quantum efficiency, without anti-reflection coating, of 21.5% under an applied bias of +40 mV with a 100% cut-off wavelength of 4.6 µm. With a dark current density of 5.21 × 10−6 A/cm2, under +40 mV applied bias and at 77 K, the photodetector exhibited a specific detectivity of 4.95 × 1011 cm·Hz1/2/W.

A Novel Surface Preparation and Post-Etch Removal Technique for InGaAs Sidewalls

1997 ◽  
Vol 477 ◽  
Author(s):  
S. A. Tabatabaei ◽  
G. A. Porkolab ◽  
S. Agarwala ◽  
F. G. Johnson ◽  
S. A. Merritt ◽  
...  
Keyword(s):  
Current Density ◽  
Dark Current ◽  
High Speed ◽  
Surface Preparation ◽  
Reverse Bias Voltage ◽  
Dark Current Density ◽  
Term Stability ◽  
Long Term Stability ◽  
Removal Technique

ABSTRACTThis paper describes in detail a surface preparation, and post-etch removal technique developed for InGaAs sidewalls. It illustrates the results demonstrating the effect of sidewall post-etch, surface preparation, and surface passivation on the performance of high speed InGaAs detectors. Dark current density for circular diodes with a diameter size varying between 10 and 100 μm was measured at a reverse bias voltage of −5 V. The effectiveness of various surface preparation techniques was studied by measuring the immediate improvement in dark current density, as well as its long-term stability. The benefits of this new technique compared to other techniques we have investigated include improved device characteristics, long-term stability, as well as a much less critical process to achieve optimum surface properties.

Sign in / Sign up

Export Citation Format

Share Document