Papers by Ikechukwu Nweze
Semiconducting pyrites were successfully deposited on glass substrates from Diethyldithiocarbamat... more Semiconducting pyrites were successfully deposited on glass substrates from Diethyldithiocarbamato iron (III) complex (single source precursor) using aerosol assisted chemical vapour deposition (AACVD) method. Structural analysis of the films shows that pure pyrite was deposited at 300 o C whereas mixture of pyrite and marcasite was deposited at 350 o C, 400 o C and 450 o C. The concentration of the precursor and deposition time has no visible effect on the structure of the deposited films. Optical analyses of the films show that pure pyrite has higher optical absorbance compared to impure pyrite. The concentration of the precursor and deposited time has significant effect on the optical properties of the deposited films. 1. INTRODUCTION In recent years, synthesis of materials for solar cell application has attracted great interest, more especially cheap and abundant materials with the properties necessary for solar energy conversion. Many of the cheap materials used in solar cell a...
Zinc Sulphide (ZnS) thin films have been deposited successfully on conducting glass substrates at... more Zinc Sulphide (ZnS) thin films have been deposited successfully on conducting glass substrates at various applied voltage using electrodeposition method. The XRD confirm the presence of ZnS thin films. Effect of applied voltage on the optical properties of ZnS thin films was investigated. Optical characterization of the films showed low absorption at low photon energy with value of 0.09, 0.32, 0.22 and 0.06 for the film deposited at 1V, 5V, 7V and 9V respectively and high absorption at high photon energy with value of 0.40, 0.81, 0.59 and 0.31 for the film deposited at 1V, 5V, 7V and 9V respectively. Thicker film was formed at 5V which indicates more favourable condition for the formation of ZnS thin films. The broadening in the XRD peaks as the applied voltage is increased showed that the crystalline size of ZnS decreases.
American Chemical Science Journal, 2013
Silver oxide was deposited on metallic substrates (zinc and lead) from silver solution with diffe... more Silver oxide was deposited on metallic substrates (zinc and lead) from silver solution with different additives at a pH of 5, dc current of 0.2A, 4V for 20seconds at 25°C. The additives were cassava solution and sugarcane juice. The metallic substrates served as cathode while a copper electrode serves as the anode. Compositions of the electrolytes were 50ml AgNO 3 , 50ml AgNO 3 and 50ml of cassava solution or 50ml of sugarcane juice. Structural and textural characterizations were carried out on the deposits. The result showed that deposition using zinc substrate gave a better result than that of lead in that the deposits were pure without impurities. Using cassava solution as additive, a pure Ag 2 O 3 deposit was obtained while sugarcane juice gave a pure intergrowth of Ag 2 O 3 and Ag 3 O 4 deposits both on zinc substrates.
Physical Science International Journal, 2015
The photovoltaic behaviour of light-emitting diodes (LEDs) was investigated at Awka (6.12⁰N, 7.05... more The photovoltaic behaviour of light-emitting diodes (LEDs) was investigated at Awka (6.12⁰N, 7.05⁰E), Nigeria, for a period of three months, January -March 2010. The LEDs were exposed to solar radiation as single units and as multiple units having 36 pieces of LEDs connected in series on one hand and in parallel on the other hand, from 600 -1800 hours each day. These irradiated LEDs were monitored for photo-generated voltage and current at hourly intervals. The solar radiation on a horizontal surface was measured using a digital luxmeter -(a Mastech Model MS6610). Ambient temperature was measured using mercury-in-glass thermometer while the photo-generated voltage and current were monitored using a standard digital multimeter. The results obtained show that voltage and current increased with the intensity of solar radiation, with maximum values recorded between 1200hours-1300hours. . The series-connected tri-colour LEDs yielded a voltage of 14.08V and a current of 23µA while the parallel unit gave a voltage of 0.47V and a current of 205μA. The tri-colour LED therefore behaved very much like a photovoltaic cell which generates a dc photovoltage of 0.5V-1V and, in short circuit, a photocurrent of some tens of milliamps as a single unit cell, but generates a dc output voltage of 12V when 28-36 cells are connected in series. In contrast, the other colours of LED yielded a relatively high voltage and current in parallel connection but low voltage and low current in series connection.
Physical Science International Journal, 2015
Pyrite semiconducting film was deposited on a glass substrate from the single source precursor (F... more Pyrite semiconducting film was deposited on a glass substrate from the single source precursor (Fe (S 2 CN(Et) 2 ) 3 ) by Aerosol Assisted Chemical Vapour Deposition (AACVD). The p-XRD pattern of the deposited films shows that pure pyrite was deposited at 300°C whereas mixture of pyrite and marcasite was deposited at 350°C, 400°C and 450°C. EDX analysis shows that semiconducting pyrite was deposited at 300°C and 350°C, whereas metallic pyrite was deposited at 400°C and 450°C.
Pyrite semiconducting film was deposited on a glass substrate from the single source precursor (F... more Pyrite semiconducting film was deposited on a glass substrate from the single source precursor (Fe (S 2 CN(Et) 2 ) 3 ) by Aerosol Assisted Chemical Vapour Deposition (AACVD). The p-XRD pattern of the deposited films shows that pure pyrite was deposited at 300°C whereas mixture of pyrite and marcasite was deposited at 350°C, 400°C and 450°C. EDX analysis shows that semiconducting pyrite was deposited at 300°C and 350°C, whereas metallic pyrite was deposited at 400°C and 450°C.
Zinc Selenide (ZnSe) thin films have been successfully deposited on two different substrates usin... more Zinc Selenide (ZnSe) thin films have been successfully deposited on two different substrates using electrodeposition method at different time intervals under direct voltage of 3V. XRD pattern of the films deposited on metallic zinc substrates are indexed to cubic crystal structure at all deposition times. The dominant orientation lies on (111) plane of reflection and also more planes of reflection are formed at high deposition time which shows that polycrystalline films were deposited. XRD pattern of the films deposited on the conducting glass (Indium doped Tin Oxide (ITO)) are indexed to wurzite (hexagonal) crystal structure. Investigation reveals that both the film thickness and the grain size of the deposited ZnSe thin films increase with the deposition time for the films deposited on the two substrates. Electrical analysis of the deposited ZnSe thin films showed that the films deposited on the metallic Zinc substrate has lower electrical resistivity than the films deposited on the ITO and the resistivity increases with the increase in the thickness of the deposited films
Semiconducting pyrites were successfully deposited on glass substrates from Diethyldithiocarbamat... more Semiconducting pyrites were successfully deposited on glass substrates from Diethyldithiocarbamato
iron (III) complex (single source precursor) using aerosol assisted chemical vapour deposition (AACVD)
method. Structural analysis of the films shows that pure pyrite was deposited at 300oC whereas mixture of pyrite
and marcasite was deposited at 350oC, 400oC and 450oC. The concentration of the precursor and deposition time
has no visible effect on the structure of the deposited films. Optical analyses of the films show that pure pyrite
has higher optical absorbance compared to impure pyrite. The concentration of the precursor and deposited time
has significant effect on the optical properties of the deposited films.
The photovoltaic behaviour of light-emitting diodes (LEDs) was investigated at Awka (6.12⁰N, 7.05... more The photovoltaic behaviour of light-emitting diodes (LEDs) was investigated at Awka (6.12⁰N, 7.05⁰E), Nigeria, for a period of three months, January - March 2010. The LEDs were exposed to solar radiation as single units and as multiple units having 36 pieces of LEDs connected in series on one hand and in parallel on the other hand, from 600 – 1800 hours each day. These irradiated LEDs were monitored for photo-generated voltage and current at hourly intervals. The solar radiation on a horizontal surface was measured using a digital luxmeter – (a Mastech Model MS6610). Ambient temperature was measured using mercury-in-glass thermometer while the photo-generated voltage and current were monitored using a standard digital multimeter. The results obtained show that voltage and current increased with the intensity of solar radiation, with maximum values recorded between 1200hours-1300hours. . The series-connected tri-colour LEDs yielded a voltage of 14.08V and a current of 23μA while the parallel unit gave a voltage of 0.47V and a current of 205μA. The tri-colour LED therefore behaved very much like a photovoltaic cell which generates a dc photovoltage of 0.5V-1V and, in short circuit, a photocurrent of some tens of milliamps as a single unit cell, but generates a dc output voltage of 12V when 28- 36 cells are connected in series. In contrast, the other colours of LED yielded a relatively high voltage and current in parallel connection but low voltage and low current in series connection.
Aims: To recover silver from industrial waste and use its solution in silver oxide deposition.
St... more Aims: To recover silver from industrial waste and use its solution in silver oxide deposition.
Study Design: Extraction, electrodeopsition on different substrates, XRD and
topographical characterizations.
Place and Duration of Study: Sample: x-ray films were collected from Anambra State
University Teaching Hospital, Awka, Nigeria. Electrodeposition at Physics and Industrial
Physics Department, Nnamdi Azikiwe University, Awka. XRD characterization was done at
Energy centre, Obafemi- Awolowo University, Ile-Ife, Nigeria in September.
Methodology: Silver was recovered from x-ray films by dissolving the silver compounds
with concentrated nitric acid. The solution thus formed was used as electrolyte in the
electrodeposition of silveroxide. Two metallic substrates (zinc and lead) were used for the
electrodeposition both serving as cathode while a copper electrode served as the anode.
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Papers by Ikechukwu Nweze
iron (III) complex (single source precursor) using aerosol assisted chemical vapour deposition (AACVD)
method. Structural analysis of the films shows that pure pyrite was deposited at 300oC whereas mixture of pyrite
and marcasite was deposited at 350oC, 400oC and 450oC. The concentration of the precursor and deposition time
has no visible effect on the structure of the deposited films. Optical analyses of the films show that pure pyrite
has higher optical absorbance compared to impure pyrite. The concentration of the precursor and deposited time
has significant effect on the optical properties of the deposited films.
Study Design: Extraction, electrodeopsition on different substrates, XRD and
topographical characterizations.
Place and Duration of Study: Sample: x-ray films were collected from Anambra State
University Teaching Hospital, Awka, Nigeria. Electrodeposition at Physics and Industrial
Physics Department, Nnamdi Azikiwe University, Awka. XRD characterization was done at
Energy centre, Obafemi- Awolowo University, Ile-Ife, Nigeria in September.
Methodology: Silver was recovered from x-ray films by dissolving the silver compounds
with concentrated nitric acid. The solution thus formed was used as electrolyte in the
electrodeposition of silveroxide. Two metallic substrates (zinc and lead) were used for the
electrodeposition both serving as cathode while a copper electrode served as the anode.
iron (III) complex (single source precursor) using aerosol assisted chemical vapour deposition (AACVD)
method. Structural analysis of the films shows that pure pyrite was deposited at 300oC whereas mixture of pyrite
and marcasite was deposited at 350oC, 400oC and 450oC. The concentration of the precursor and deposition time
has no visible effect on the structure of the deposited films. Optical analyses of the films show that pure pyrite
has higher optical absorbance compared to impure pyrite. The concentration of the precursor and deposited time
has significant effect on the optical properties of the deposited films.
Study Design: Extraction, electrodeopsition on different substrates, XRD and
topographical characterizations.
Place and Duration of Study: Sample: x-ray films were collected from Anambra State
University Teaching Hospital, Awka, Nigeria. Electrodeposition at Physics and Industrial
Physics Department, Nnamdi Azikiwe University, Awka. XRD characterization was done at
Energy centre, Obafemi- Awolowo University, Ile-Ife, Nigeria in September.
Methodology: Silver was recovered from x-ray films by dissolving the silver compounds
with concentrated nitric acid. The solution thus formed was used as electrolyte in the
electrodeposition of silveroxide. Two metallic substrates (zinc and lead) were used for the
electrodeposition both serving as cathode while a copper electrode served as the anode.