scholarly journals Ternary Composite of Co-Doped CdSe@electrospun Carbon Nanofibers: A Novel Reusable Visible Light-Driven Photocatalyst with Enhanced Performance

Catalysts ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 348 ◽  
Author(s):  
Gopal Panthi ◽  
Oh Hoon Kwon ◽  
Yun-Su Kuk ◽  
Kapil Raj Gyawali ◽  
Yong Wan Park ◽  
...  

In this work, flexible ternary composites of cobalt-doped cadmium selenide/electrospun carbon nanofibers (Co-CdSe@ECNFs) for photocatalytic applications were fabricated successfully via electrospinning, followed by carbonization. For the fabrication of the proposed photocatalysts, Co-CdSe nanoparticles were grown in situ on the surface of ECNFs during the carbonization of precursor electrospun nanofibers obtained by dispersing Se powder in the electrospinning solution of polyacrylonitrile/N,N-Dimethylformamide (PAN/DMF) containing Cd2+ and Co2+. The photocatalytic performance of synthesized samples is investigated in the photodegradation of methylene blue (MB) and rhodamine B (RhB) dyes. Experimental results revealed the superior photocatalytic efficiency of Co-CdSe@ECNFs over undoped samples (CdSe@ECNFs) due to the doping effect of cobalt, which is able to capture the photogenerated electrons to prevent electron–hole recombination, thereby improving photocatalytic performance. Moreover, ECNFs could play an important role in enhancing electron transfer and optical absorption of the photocatalyst. This type of fabrication strategy may be a new avenue for the synthesis of other ECNF-based ternary composites.

2018 ◽  
Vol 281 ◽  
pp. 848-853
Author(s):  
Ling Fang Qiu ◽  
Xiao Bin Qiu ◽  
Zhi Wei Zhou ◽  
Shu Wang Duo

Graphitic carbon nitride is a promising photocatalyst for environmental purification, but the photocatalytic performance is limited significantly due to its narrow visible-light adsorption and high photo-reduced electron-hole recombination rate. This work developed a novel way to overcome the two defects and obtained obvious effect. CoAPO-5 was used to broaden visible-light adsorption range by conducting g-C3N4/CoAPO-5 binary composite. In further, rGO was integrated into the binary system to form novel ternary composite. rGO performs as a electron mediator, which can inhibit photo-reduced electron-hole recombination efficiently. The samples were characterized by XRD, SEM, PL, IR and DRS. The photocatalytic performances for degrading RhB (10mg/L) indicated that g-C3N4/CoAPO-5/rGO have much higher activity than g-C3N4/CoAPO-5 because of synergistic effect. When the doping content of rGO in g-C3N4/CoAPO-5 was 0.5%, the degradation efficiency was improved by 14%.


2020 ◽  
Author(s):  
Zhaoqing Li ◽  
Zhufeng Liu ◽  
Xiao Yang ◽  
Peng Chen ◽  
Lei Yang ◽  
...  

Abstract According to the composite design, a series of black TiO2/graphene composites were synthesized to improve its photocatalytic activity. TiO2 is generated in situ on the surface of graphene by a facile sol-gel method. The combination of graphene and TiO2 was beneficial for eliminating the opportunity of photogenerated electron-hole recombination due to the excellent conductivity of graphene. In the subsequent hydrogenation process, the self-doping Ti3+ was introduced accompanied by the crystallization of amorphous TiO2. The narrowed bandgap caused by self-doping Ti3+ enhanced the visible light absorption and make the composites appear black. Both of them improved the photocatalytic performance of the synthesized black TiO2/graphene composites. The band structure of the composite was analyzed by valence band XPS, revealing the reason for the high visible light catalytic performance of the composite. The results proved that the black TiO2/graphene composites synthesized show attractive potential for applications in environmental and energy issues.


2020 ◽  
Vol 10 (9) ◽  
pp. 3238
Author(s):  
Min Liu ◽  
Guangxin Wang ◽  
Panpan Xu ◽  
Yanfeng Zhu ◽  
Wuhui Li

In this study, the Ag3PO4/SnO2 heterojunction on carbon cloth (Ag3PO4/SnO2/CC) was successfully fabricated via a facile two-step process. The results showed that the Ag3PO4/SnO2/CC heterojunction exhibited a remarkable photocatalytic performance for the degradation of Rhodamine B (RhB) and methylene blue (MB), under visible light irradiation. The calculated k values for the degradation of RhB and MB over Ag3PO4/SnO2/CC are 0.04716 min−1 and 0.04916 min−1, which are higher than those calculated for the reactions over Ag3PO4/SnO2, Ag3PO4/CC and SnO2/CC, respectively. The enhanced photocatalytic activity could mainly be attributed to the improved separation efficiency of photogenerated electron-hole pairs, after the formation of the Ag3PO4/SnO2/CC heterojunction. Moreover, carbon cloth with a large specific surface area and excellent conductivity was used as the substrate, which helped to increase the contact area of dye solution with photocatalysts and the rapid transfer of photogenerated electrons. Notably, when compared with the powder catalyst, the catalysts supported on carbon cloth are easier to quickly recycle from the pollutant solution, thereby reducing the probability of recontamination.


2020 ◽  
Vol 13 (05) ◽  
pp. 2051031
Author(s):  
Abulikemu Abulizi ◽  
Hujiabudula Maimaitizi ◽  
Dilinuer Talifu ◽  
Yalkunjan Tursun

A photocatalyst of high-performance hierarchical nitrogen-doped MoS2 (N-MoS2) microsphere was fabricated by an in situ hydrothermal method in the presence of cetyltrimethylammonium bromide (CTAB). The as-prepared N-MoS2 microsphere was self-assembled by extremely thin interleaving petals, where CTAB acts as a nucleation site for the formation of the interleaving petals due to the strong interaction between CTA+ and [Formula: see text]. N-MoS2 showed higher N2 fixation ability (101.2 [Formula: see text] mol/g(cat)h) than the non-doped MoS2 under the visible light irradiation, and the improved photocatalytic activity could be ascribed to that the doped N narrows the band gap, and the surface reflecting and scattering effect caused by the hierarchical structure enhance the light adsorption. The trapping experiment of active species was also investigated to evaluate the role of photogenerated electrons in the photocatalytic reaction process. Meanwhile, the possible mechanism for the formation and excellent photocatalytic performance of N-MoS2 microsphere were also presented.


2014 ◽  
Vol 2 (15) ◽  
pp. 5315-5322 ◽  
Author(s):  
Lan Ching Sim ◽  
Kah Hon Leong ◽  
Shaliza Ibrahim ◽  
Pichiah Saravanan

GO–Ag–TNTs, a ternary composite was synthesized. Both Ag and GO well contributed to enhance the photocatalytic activity in the visible region.


2008 ◽  
Vol 2008 ◽  
pp. 1-7 ◽  
Author(s):  
Yonggang Sheng ◽  
Yao Xu ◽  
Dong Jiang ◽  
Liping Liang ◽  
Dong Wu ◽  
...  

Using a facile hydrothermal method, N-Br-codopedTiO2photocatalyst that had intense absorption in visible region was prepared at low temperature (100°C), through a direct reaction between nanocrystalline anataseTiO2solution and cetyltrimethylammonium bromide (CTAB). The results of X-ray photoelectron spectroscopy (XPS) showed the existence of N-Ti-N, O-Ti-N-R,Ti3+(attribute to the doped Br atoms by charge compensation), andTiOxNyspecies, indicating the successful codoping of N and Br atoms, which were substituted for lattice oxygen without any influence on the crystalline phase ofTiO2. In contrast to the N-doped sample, the N-Br-codopedTiO2photocatalyst could more readily photodegrade methylene blue (MB) under visible-light irradiation. The visible-light catalytic activity of thus-prepared photocatalyst resulted from the synergetic effect of the doped nitrogen and bromine, which not only gave high absorbance in the visible-light range, but also reduced electron-hole recombination rate.


Crystals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 432 ◽  
Author(s):  
Yun-hui Si ◽  
Ya-yun Li ◽  
Yu Xia ◽  
Shao-ke Shang ◽  
Xin-bo Xiong ◽  
...  

In this work, a novel metal-organic framework (MOF) and BiVO4 (BVO) composite photocatalyst was successfully synthesized by an in-situ growth method. The characterization of obtained samples was done by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, N2 adsorption, and photoluminescence spectroscopy. The photocatalytic performance of ZIF-8@BiVO4 composite was evaluated by the degradation of methylene blue (MB) under simulated visible light irradiation. Compared with the mixture of BVO and ZIF-8, the composite photocatalyst exhibited superior photodegradation efficiency, which could be attributed to the synergistic effect between BVO and ZIF-8. The reduced recombination of photogenerated electrons and holes was considered to be an important reason for the enhancement of photocatalytic performance. This design demonstrates a rational method to improve the photocatalytic performance by combining photocatalysts with MOFs.


RSC Advances ◽  
2015 ◽  
Vol 5 (78) ◽  
pp. 63264-63270 ◽  
Author(s):  
Lei Shi ◽  
Lin Liang ◽  
Fangxiao Wang ◽  
Mengshuai Liu ◽  
Tao Liang ◽  
...  

pg-C3N4 prepared through in situ bubble template showed large surface area and low recombination rate of photoinduced electron–hole pairs, leading to enhanced visible-light photocatalytic activity for degrading pollutants and splitting water to H2.


Sign in / Sign up

Export Citation Format

Share Document