Limits...
Ag2S/CdS/TiO2 Nanotube Array Films with High Photocurrent Density by Spotting Sample Method.

Sun H, Zhao P, Zhang F, Liu Y, Hao J - Nanoscale Res Lett (2015)

Bottom Line: The X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectrum (XPS) results demonstrated that the Ag2S/CdS/TNTs prepared by SSM and other films were successfully prepared.The cycles of local deposition have great influence on their photoelectric properties.The photocurrent density of Ag2S/CdS/TNTs by SSM with optimum deposition cycles of 6 was about 37 times that of TNTs without modification, demonstrating their great prospective applications in solar energy utilization fields.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Colloid and Interface Chemistry & Key Laboratory of Special Aggregated Materials, Shandong University, Ministry of Education, Jinan, 250100, People's Republic of China.

ABSTRACT
Ag2S/CdS/TiO2 hybrid nanotube array films (Ag2S/CdS/TNTs) were prepared by selectively depositing a narrow-gap semiconductor-Ag2S (0.9 eV) quantum dots (QDs)-in the local domain of the CdS/TiO2 nanotube array films by spotting sample method (SSM). The improvement of sunlight absorption ability and photocurrent density of titanium dioxide (TiO2) nanotube array films (TNTs) which were obtained by anodic oxidation method was realized because of modifying semiconductor QDs. The CdS/TNTs, Ag2S/TNTs, and Ag2S/CdS/TNTs fabricated by uniformly depositing the QDs into the TNTs via the successive ionic layer adsorption and reaction (SILAR) method were synthesized, respectively. The X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectrum (XPS) results demonstrated that the Ag2S/CdS/TNTs prepared by SSM and other films were successfully prepared. In comparison with the four films of TNTs, CdS/TNTs, Ag2S/TNTs, and Ag2S/CdS/TNTs by SILAR, the Ag2S/CdS/TNTs prepared by SSM showed much better absorption capability and the highest photocurrent density in UV-vis range (320~800 nm). The cycles of local deposition have great influence on their photoelectric properties. The photocurrent density of Ag2S/CdS/TNTs by SSM with optimum deposition cycles of 6 was about 37 times that of TNTs without modification, demonstrating their great prospective applications in solar energy utilization fields.

No MeSH data available.


Related in: MedlinePlus

A The I-t curves of the five films under intermittent illumination of UV and visible light (320–800 nm) at bias voltages of 0 V vs. reference electrode Hg/Hg2Cl2. B The I-t curves of the five different anodes under intermittent illumination of visible light (λ > 420 nm). C The photocurrent response of the array films of Ag2S/CdS/TNTs by SSM with different deposition cycles. D The photocurrent-response of pure TNTs to the incident light with various wavelengths is principally active in the UV light region. TNTs (a), CdS/TNTs (b), Ag2S/TNTs (c), Ag2S/CdS/TNTs by SSM (d), and Ag2S/CdS/TNTs via SILAR (e)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4591224&req=5

Fig8: A The I-t curves of the five films under intermittent illumination of UV and visible light (320–800 nm) at bias voltages of 0 V vs. reference electrode Hg/Hg2Cl2. B The I-t curves of the five different anodes under intermittent illumination of visible light (λ > 420 nm). C The photocurrent response of the array films of Ag2S/CdS/TNTs by SSM with different deposition cycles. D The photocurrent-response of pure TNTs to the incident light with various wavelengths is principally active in the UV light region. TNTs (a), CdS/TNTs (b), Ag2S/TNTs (c), Ag2S/CdS/TNTs by SSM (d), and Ag2S/CdS/TNTs via SILAR (e)

Mentions: Figure 8a shows the I-t curves of the five films under intermittent illumination of UV and visible light (320–800 nm) at bias voltages of 0 V vs. reference electrode Hg/Hg2Cl2. TNTs, CdS/TNTs, Ag2S/TiO2, and Ag2S/CdS/TNTs by SSM show an instantaneous change in current upon illumination and the current responses in the dark are negligible, indicating that the separation of the electrons and holes of the above four array films is prompt and the charge transport inside the films is fast. The photocurrent density of Ag2S/CdS/TNTs by SSM (average 4.5 mA/cm2) is higher than that of CdS/TNTs (average 3.0 mA/cm2). Unlike CdS/TNTs and Ag2S/CdS/TNTs by SSM, the TNTs, Ag2S/TNTs, and Ag2S/CdS/TNTs via SILAR show very low photocurrent density values under Xe light irradiation. Photocurrent density of hybrid Ag2S/CdS/TNTs by SSM is about 37 times higher than that of pure TNTs (average 0.14 mA/cm2). Interestingly, the photocurrent of the array films of Ag2S/CdS/TNTs via SILAR is very small and decreases gradually, demonstrating that the photoelectrons and holes may recombine rapidly. These results indicate that more free carriers are generated and quickly transfer in Ag2S/CdS/TNTs by SSM than in other array films. Figure 8b shows the I-t curves of the five different anodes under intermittent illumination of visible light (λ > 420 nm). Similar to Fig. 8a, the photocurrent density of Ag2S/CdS/TNTs by SSM (average 2.8 mA/cm2) and CdS/TNTs (average 1.8 mA/cm2) is much higher than that of TNTs, Ag2S/TNTs, and Ag2S/CdS/TNTs via SILAR, which indicates lower visible light response of pure TNTs. Figure 8c provides the photocurrent response of the array films of Ag2S/CdS/TNTs by SSM with different deposition cycles. Ag2S/CdS/TNTs by SSM with 6 deposition cycles generates the largest photocurrent than those of the samples with different deposition cycles. The incident photon to current efficiency (IPCE) test of the five different films (TNTs, CdS/TNTs, Ag2S/TNTs, Ag2S/CdS/TNTs by SSM, and Ag2S/CdS/TNTs via SILAR) was carried out at 0 V vs. Hg/Hg2Cl2. As shown in Fig. 8d, the photo-response of pure TNTs to the incident light with various wavelengths is principally active in the UV light region. Compared with TNTs, CdS/TNTs and Ag2S/CdS/TNTs by SSM exhibit higher IPCE value, and Ag2S/CdS/ TNTs by SSM shows the highest photocurrent conversion efficiency at a wavelength range between 320 and 600 nm. However, the IPCE value of Ag2S/TNTs and Ag2S/CdS/TNTs via SILAR is lower than that of TNTs at a wavelength from 330 to 500 nm.Fig. 8


Ag2S/CdS/TiO2 Nanotube Array Films with High Photocurrent Density by Spotting Sample Method.

Sun H, Zhao P, Zhang F, Liu Y, Hao J - Nanoscale Res Lett (2015)

A The I-t curves of the five films under intermittent illumination of UV and visible light (320–800 nm) at bias voltages of 0 V vs. reference electrode Hg/Hg2Cl2. B The I-t curves of the five different anodes under intermittent illumination of visible light (λ > 420 nm). C The photocurrent response of the array films of Ag2S/CdS/TNTs by SSM with different deposition cycles. D The photocurrent-response of pure TNTs to the incident light with various wavelengths is principally active in the UV light region. TNTs (a), CdS/TNTs (b), Ag2S/TNTs (c), Ag2S/CdS/TNTs by SSM (d), and Ag2S/CdS/TNTs via SILAR (e)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4591224&req=5

Fig8: A The I-t curves of the five films under intermittent illumination of UV and visible light (320–800 nm) at bias voltages of 0 V vs. reference electrode Hg/Hg2Cl2. B The I-t curves of the five different anodes under intermittent illumination of visible light (λ > 420 nm). C The photocurrent response of the array films of Ag2S/CdS/TNTs by SSM with different deposition cycles. D The photocurrent-response of pure TNTs to the incident light with various wavelengths is principally active in the UV light region. TNTs (a), CdS/TNTs (b), Ag2S/TNTs (c), Ag2S/CdS/TNTs by SSM (d), and Ag2S/CdS/TNTs via SILAR (e)
Mentions: Figure 8a shows the I-t curves of the five films under intermittent illumination of UV and visible light (320–800 nm) at bias voltages of 0 V vs. reference electrode Hg/Hg2Cl2. TNTs, CdS/TNTs, Ag2S/TiO2, and Ag2S/CdS/TNTs by SSM show an instantaneous change in current upon illumination and the current responses in the dark are negligible, indicating that the separation of the electrons and holes of the above four array films is prompt and the charge transport inside the films is fast. The photocurrent density of Ag2S/CdS/TNTs by SSM (average 4.5 mA/cm2) is higher than that of CdS/TNTs (average 3.0 mA/cm2). Unlike CdS/TNTs and Ag2S/CdS/TNTs by SSM, the TNTs, Ag2S/TNTs, and Ag2S/CdS/TNTs via SILAR show very low photocurrent density values under Xe light irradiation. Photocurrent density of hybrid Ag2S/CdS/TNTs by SSM is about 37 times higher than that of pure TNTs (average 0.14 mA/cm2). Interestingly, the photocurrent of the array films of Ag2S/CdS/TNTs via SILAR is very small and decreases gradually, demonstrating that the photoelectrons and holes may recombine rapidly. These results indicate that more free carriers are generated and quickly transfer in Ag2S/CdS/TNTs by SSM than in other array films. Figure 8b shows the I-t curves of the five different anodes under intermittent illumination of visible light (λ > 420 nm). Similar to Fig. 8a, the photocurrent density of Ag2S/CdS/TNTs by SSM (average 2.8 mA/cm2) and CdS/TNTs (average 1.8 mA/cm2) is much higher than that of TNTs, Ag2S/TNTs, and Ag2S/CdS/TNTs via SILAR, which indicates lower visible light response of pure TNTs. Figure 8c provides the photocurrent response of the array films of Ag2S/CdS/TNTs by SSM with different deposition cycles. Ag2S/CdS/TNTs by SSM with 6 deposition cycles generates the largest photocurrent than those of the samples with different deposition cycles. The incident photon to current efficiency (IPCE) test of the five different films (TNTs, CdS/TNTs, Ag2S/TNTs, Ag2S/CdS/TNTs by SSM, and Ag2S/CdS/TNTs via SILAR) was carried out at 0 V vs. Hg/Hg2Cl2. As shown in Fig. 8d, the photo-response of pure TNTs to the incident light with various wavelengths is principally active in the UV light region. Compared with TNTs, CdS/TNTs and Ag2S/CdS/TNTs by SSM exhibit higher IPCE value, and Ag2S/CdS/ TNTs by SSM shows the highest photocurrent conversion efficiency at a wavelength range between 320 and 600 nm. However, the IPCE value of Ag2S/TNTs and Ag2S/CdS/TNTs via SILAR is lower than that of TNTs at a wavelength from 330 to 500 nm.Fig. 8

Bottom Line: The X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectrum (XPS) results demonstrated that the Ag2S/CdS/TNTs prepared by SSM and other films were successfully prepared.The cycles of local deposition have great influence on their photoelectric properties.The photocurrent density of Ag2S/CdS/TNTs by SSM with optimum deposition cycles of 6 was about 37 times that of TNTs without modification, demonstrating their great prospective applications in solar energy utilization fields.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Colloid and Interface Chemistry & Key Laboratory of Special Aggregated Materials, Shandong University, Ministry of Education, Jinan, 250100, People's Republic of China.

ABSTRACT
Ag2S/CdS/TiO2 hybrid nanotube array films (Ag2S/CdS/TNTs) were prepared by selectively depositing a narrow-gap semiconductor-Ag2S (0.9 eV) quantum dots (QDs)-in the local domain of the CdS/TiO2 nanotube array films by spotting sample method (SSM). The improvement of sunlight absorption ability and photocurrent density of titanium dioxide (TiO2) nanotube array films (TNTs) which were obtained by anodic oxidation method was realized because of modifying semiconductor QDs. The CdS/TNTs, Ag2S/TNTs, and Ag2S/CdS/TNTs fabricated by uniformly depositing the QDs into the TNTs via the successive ionic layer adsorption and reaction (SILAR) method were synthesized, respectively. The X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectrum (XPS) results demonstrated that the Ag2S/CdS/TNTs prepared by SSM and other films were successfully prepared. In comparison with the four films of TNTs, CdS/TNTs, Ag2S/TNTs, and Ag2S/CdS/TNTs by SILAR, the Ag2S/CdS/TNTs prepared by SSM showed much better absorption capability and the highest photocurrent density in UV-vis range (320~800 nm). The cycles of local deposition have great influence on their photoelectric properties. The photocurrent density of Ag2S/CdS/TNTs by SSM with optimum deposition cycles of 6 was about 37 times that of TNTs without modification, demonstrating their great prospective applications in solar energy utilization fields.

No MeSH data available.


Related in: MedlinePlus