<abstract xmlns="http://www.w3.org/1999/xhtml">

In this paper, energy band gaps and electrical conductivity based on aluminum selenide (Al2Se3) thin films are synthesized electrochemically using cathodic deposition technique, with graphite and carbon as cathode and anode, respectively. Synthesis is done at 353 K from an aqueous solution of analytical grade selenium dioxide (SeO2), and aluminum chloride (AlCl2·7H2O). Junctions-based Al2Se3 thin films from a controlled medium of pH 2.0 are deposited on fluorine-doped tin oxide (FTO) substrate using potential voltages varying from 1,000 mV to 1,400 mV and 3 minutes −15 minutes respectively. The films were characterized for optical properties and electrical conductivity using UV-vis and photoelectrochemical cells (PEC) spectroscopy. The PEC reveals a transition in the conduction of the films from p-type to n-type as the potential voltage varies. The energy band gap reduces from 3.2 eV to 2.9 eV with an increase in voltage and 3.3 eV to 2.7 eV with increase in time. These variations indicate successful fabrication of junction-based Al2Se3 thin films with noticeable transition in the conductivity type and energy band gap of the materials. Consequently, the fabricated Al2Se3 can find useful applications in optoelectronic devices.
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In this paper, energy band gaps and electrical conductivity based on aluminum selenide (Al2Se3) thin films are synthesized electrochemically using cathodic deposition technique, with graphite and carbon as cathode and anode, respectively. Synthesis is done at 353 K from an aqueous solution of analytical grade selenium dioxide (SeO2), and aluminum chloride (AlCl2·7H2O). Junctions-based Al2Se3 thin films from a controlled medium of pH 2.0 are deposited on fluorine-doped tin oxide (FTO) substrate using potential voltages varying from 1,000 mV to 1,400 mV and 3 minutes −15 minutes respectively. The films were characterized for optical properties and electrical conductivity using UV-vis and photoelectrochemical cells (PEC) spectroscopy. The PEC reveals a transition in the conduction of the films from p-type to n-type as the potential voltage varies. The energy band gap reduces from 3.2 eV to 2.9 eV with an increase in voltage and 3.3 eV to 2.7 eV with increase in time. These variations indicate successful fabrication of junction-based Al2Se3 thin films with noticeable transition in the conductivity type and energy band gap of the materials. Consequently, the fabricated Al2Se3 can find useful applications in optoelectronic devices.

Optoelectronics applications of electrodeposited p- and n-type Al2Se3 thin films

Condensed Matter and Statistical Physics Research Unit, Department of Physics, School of Sciences

Basic Sciences Department, Physics/Electronics Unit

Materials Science-Poland

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Optoelectronics applications of electrodeposited p- and n-type AlSe thin films

In this paper, energy band gaps and electrical conductivity based on aluminum selenide (Al2Se3) thin films are synthesized electrochemically using cathodic...

Film thickness as the time of deposition increases		Film thickness as the cathodic potential increases

Time (min)	Thickness (nm)	Cathodic potential (mV)	Thickness (nm)
3	193	1,000	234
6	233	1,100	344
9	399	1,200	522
12	476	1,300	714
15	592	1,400	773

Semiconductor type and energy band gaps

As time of deposition increases			As voltage increases

Time (min)	Type	Eg (eV)	Cathodic potential (mV)	Type	Eg (eV)
3	N	3.30	1,000	P	3.23
6	N	3.19	1,100	I-Intrinsic	3.20
9	N	2.83	1,200	N	3.00
12	N	2.79	1,300	N	2.96
15	N	2.70	1,400	N	2.95

Optoelectronics applications of electrodeposited p- and n-type Al₂Se₃ thin films

Online veröffentlicht: 02. Sept. 2021

Seitenbereich: 166 - 171

Eingereicht: 20. Feb. 2021

Akzeptiert: 25. Feb. 2021

DOI: https://doi.org/10.2478/msp-2021-0011

Schlüsselwörter
electrodeposition, cathodic graphide, p- and n-type AlSe, energy gap

© 2021 A. A. Faremi et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Film thickness values with the variation in the time of deposition and cathodic potential.

Measured material properties as a function of deposition time and cathodic potential based on UV and PEC results.

Optoelectronics applications of electrodeposited p- and n-type Al2Se3 thin films

Online veröffentlicht: 02. Sept. 2021

Seitenbereich: 166 - 171

Eingereicht: 20. Feb. 2021

Akzeptiert: 25. Feb. 2021

DOI: https://doi.org/10.2478/msp-2021-0011

Schlüsselwörterelectrodeposition, cathodic graphide, p- and n-type AlSe, energy gap

© 2021 A. A. Faremi et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Film thickness values with the variation in the time of deposition and cathodic potential.

Measured material properties as a function of deposition time and cathodic potential based on UV and PEC results.

Optoelectronics applications of electrodeposited p- and n-type Al₂Se₃ thin films

Schlüsselwörter
electrodeposition, cathodic graphide, p- and n-type AlSe, energy gap