Highly visible-light luminescence properties of the carboxyl-functionalized short and ultrashort MWNTs

Luo, Yongsong; Xia, Xiaohong; Liang, Ying; Zhang, Yonggang; Ren, Qinfeng; Li, Jialin; Zeng, Jia; Tang, Yiwen

doi:10.1016/j.jssc.2007.05.002

Cited by 18 publications

(12 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition to those mentioned above, an alternative explanation for fluorescence in GO has been proposed by Pan et al, 91 suggesting that the blue emission might have originated from free zigzag sites with a carbene-like triplet ground state described as s 1 p 1 . Furthermore, fluorescence from carbon nanoparticles [92][93][94] and functionalized carbon nanotubes has been ascribed to the presence of oxygen-containing functional groups, 95 in a similar way to the mechanism reported for surface-oxidized silicon nanocrystals. 96 However, the observed enhancement of blue fluorescence with reduction suggests that oxygen functional groups can be excluded as the origin.…”

Section: Annealing Rgo In Nhsupporting

confidence: 63%

See 1 more Smart Citation

Significant enhancement of blue emission and electrical conductivity of N-doped graphene

et al. 2012

View full text Add to dashboard Cite

Section: Annealing Rgo In Nhsupporting

confidence: 63%

“…However, after oxidation, the (002) peak shifted to a lower angle of around 11.11 and the d-spacing of GO increased to 7. 95 A. Such d-spacing is significantly larger than that of single-layer graphene ($3.40 A), indicating that GO contains large numbers of oxygen-containing functional groups on both sides of the graphene sheets.…”

Section: Annealing Rgo In Nhmentioning

confidence: 87%

Significant enhancement of blue emission and electrical conductivity of N-doped graphene

et al. 2012

View full text Add to dashboard Cite

“…3. The argument is based on the fact that the fluorescence originates from the oxygeneous functional groups as seen earlier in the case of carbon nanoparticles, 75,76,95 functionalized CNTs 74,96 and surface-oxidized Si nanocrystals. 97 However, Loh et al 6 suggest that the enhancement of fluorescence with reduction excludes oxygen containing functional groups from the possible origin.…”

Section: Mechanism Of Fluorescencementioning

confidence: 99%

Fluorescence from graphene oxide and the influence of ionic, π–π interactions and heterointerfaces: electron or energy transfer dynamics

Vempati

Uyar

2014

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

2D crystals such as graphene and its oxide counterpart have sought good research attention for their application as well as fundamental interest. Especially graphene oxide (GO) is quite interesting because of its versatility and diverse application potential. However the mechanism of fluorescence from GO is under severe discussion. To explain the emission in general two interpretations were suggested, viz localization of sp(2) clusters and involvement of oxygeneous functional groups. Despite this disagreement, it should be acknowledged that the heterogeneous atomic structure, synthesis dependent and uncontrollable implantation of oxygen functional groups on the basal plane make such explanations more difficult. Nevertheless, a suitable explanation enhances the applicability of the material which also enables the design of novel materials. At this juncture we believe that given the complexity in understanding the emission mechanism it would be very useful to review the literature. In this perspective we juxtapose various results related to fluorescence and influencing factors so that a conclusive interpretation may be unveiled. Apparently, the existing interpretations have largely ignored the factors such as self-rolling, byproduct formation etc. Vis-a-vis previous reviews did not discuss the interfacial charge transfer across heterostructures and the implication on the optical properties of GO or reduced graphene oxide (rGO). Such analysis would be very insightful to determine the energetic location of sub band gap states. Moreover, ionic and π-π type interactions are also considered for their influence on emission properties. Apart from these, quantum dots, covalent modifications and nonlinear optical properties of GO and rGO were discussed for completeness. Finally we made concluding remarks with outlook.

show abstract

“…The CNTs and N-CNTs were purified from catalyst residues by treatment with a mixture of concentrated acids (HF, HCl, and HNO 3 ) at 60°C for 3 h [10]. The purified CNTs and N-CNTs were functionalized by two methods so as to vary the ratio between the hydroxyl and carboxyl groups on their surface [8]: by oxidation in an acidic medium with potassium permanganate at 60°C (CNT| f1 and N-CNT| f1 ) or at room temperature in the presence of the surface catalyst Aliquat 336 (Aldrich) (CNT| f2 and N-CNT| f2 ).…”

Section: Methodsmentioning

confidence: 99%

Effect of Carbon Nanotube Functionalization on the Structure and Electrochemical Characteristics of Their Hybrid Nanocomposites with Polyaniline and Polypyrrole

et al. 2014

View full text Add to dashboard Cite

Hybrid nanocomposites were prepared on the basis of polyaniline (PAn) and polypyrrole (PPy) with functionalized multiwall carbon nanotubes (CNTs). It was shown that the method of functionalization of the CNT and the nature of the polymer have a substantial effect on the structure and electrochemical characteristics of the synthesized nanocomposites. It was established that the conductivity and the capacity characteristics of the PPy/CNT nanocomposites are determined largely by the content of carbon nanotubes, whereas for the PAn/CNT materials they are also determined by the method of functionalization of the CNT. It was shown that the highest capacity (366 and 294 F/g) is characteristic of the nanocomposites based on PAn and CNT (N-CNT) functionalized with the surface catalyst Aliquat 336.In recent years electrically conducting polymers (ECPs) have attracted considerable interest as electrode materials for the creation of various energy-converting devices and supercapacitors in particular thanks to their inherent conductivity and their ability to undergo reversible redox transitions [1,2]. At the same time the main drawback of supercapacitors based on ECPs is their relatively low stability during repeated charge/discharge cycles since they can lose their conductivity as a result of volume changes that occur during cycling [3]. On the other hand, the electrochemical activity of the ECP is limited to a specific range of potentials, and this can give rise to their degradation during over-oxidation.Along with ECPs promising materials for the creation of a new generation of supercapacitors are carbon nanotubes (CNTs), which have a fairly large surface area, relatively high conductivity, and excellent mechanical characteristics [4]. Compared with ECPs, however, they have appreciably lower specific capacity [4,5]. In view of this the creation of new composite nanomaterials based on ECPs and CNTs for the electrodes of supercapacitors that would combine the best characteristics of both components may prove extremely attractive [1,3,6].On account of their insolubility simple mechanical mixing of the CNT and ECP does not give the desired results since the CNTs are not uniformly dispersed in the polymeric matrix (also because the initial CNTs are present in the form of bundles) 204

show abstract

Highly visible-light luminescence properties of the carboxyl-functionalized short and ultrashort MWNTs

Cited by 18 publications

References 41 publications

Significant enhancement of blue emission and electrical conductivity of N-doped graphene

Significant enhancement of blue emission and electrical conductivity of N-doped graphene

Fluorescence from graphene oxide and the influence of ionic, π–π interactions and heterointerfaces: electron or energy transfer dynamics

Effect of Carbon Nanotube Functionalization on the Structure and Electrochemical Characteristics of Their Hybrid Nanocomposites with Polyaniline and Polypyrrole

Contact Info

Product

Resources

About