High-yield synthesis of carbon nanotubes in-situ on iron ore tailing

Costal, Glauber Zerbini; Oliveira, Cláudio Ernani Martins; Morais, Evandro Augusto de; Oliveira, Carlos Augusto de; Silva, Edelma Eleto da; Filho, Francisco Moura; Geraldo, Viviany

doi:10.1016/j.cartre.2021.100098

Cited by 9 publications

(2 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…, citric acid and urea) and allows synthesizing CDs with a narrower size distribution and a controlled structure, which contribute to an appropriate fluorescence quantum yield (QY) and stability. , Because there are many starting monomers exploitable in the preparation of CDs whose tuning can lead to an endless number of CDs with tailor-made properties, the bottom-up strategy is considered much more flexible and efficient if compared with other protocols. However, one of the most limiting drawbacks of CDs is the extremely low reaction yield obtained up to now (<3% w/w) . Calcination- and microwave-assisted protocols have been proven to give rise to a higher yield synthesis (25–30% w/w), but the broader size distributions and severe structural heterogeneity are unsuitable for pharmaceutical applications. , Therefore, there is an urgency to develop high-reaction-yield protocols to prepare homogeneous CDs with controlled properties for real-world applications.…”

Section: Introductionmentioning

confidence: 99%

“…However, one of the most limiting drawbacks of CDs is the extremely low reaction yield obtained up to now (<3% w/w). 6 Calcination-and microwaveassisted protocols have been proven to give rise to a higher yield synthesis (25−30% w/w), but the broader size distributions and severe structural heterogeneity are unsuitable for pharmaceutical applications. 7,8 Therefore, there is an urgency to develop high-reaction-yield protocols to prepare homogeneous CDs with controlled properties for real-world applications.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Decagram-Scale Synthesis of Multicolor Carbon Nanodots: Self-Tracking Nanoheaters with Inherent and Selective Anticancer Properties

Mauro

Utzeri

Sciortino

et al. 2022

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Carbon nanodots (CDs) are a new class of carbon-based nanoparticles endowed with photoluminescence, high specific surface area, and good photothermal conversion, which have spearheaded many breakthroughs in medicine, especially in drug delivery and cancer theranostics. However, the tight control of their structural, optical, and biological properties and the synthesis scale-up have been very difficult so far. Here, we report for the first time an efficient protocol for the one-step synthesis of decagram-scale quantities of N,S-doped CDs with a narrow size distribution, along with a single nanostructure multicolor emission, high near-infrared (NIR) photothermal conversion efficiency, and selective reactive oxygen species (ROS) production in cancer cells. This allows achieving targeted and multimodal cytotoxic effects (i.e., photothermal and oxidative stresses) in cancer cells by applying biocompatible NIR laser sources that can be remotely controlled under the guidance of fluorescence imaging. Hence, our findings open up a range of possibilities for real-world biomedical applications, among which is cancer theranostics. In this work, indocyanine green is used as a bidentate SO x donor which has the ability to tune surface groups and emission bands of CDs obtained by solvothermal decomposition of citric acid and urea in N,N-dimethylformamide. The co-doping implies various surface states providing transitions in the visible region, thus eliciting a tunable multicolor emission from blue to red and excellent photothermal efficiency in the NIR region useful in bioimaging applications and image-guided anticancer phototherapy. The fluorescence self-tracking capability of SO x –CDs reveals that they can enter cancer cells more quickly than healthy cell lines and undergo a different intracellular fate after cell internalization. This could explain why sulfur doping entails pro-oxidative activities by triggering more ROS generation in cancer cells when compared to healthy cell lines. We also find that oxidative stress can be locally enhanced under the effects of a NIR laser at moderate power density (2.5 W cm–2). Overall, these findings suggest that SO x –CDs are endowed with inherent drug-independent cytotoxic effects toward cancer cells, which would be selectively enhanced by external NIR light irradiation and helpful in precision anticancer approaches. Also, this work opens a debate on the role of CD surface engineering in determining nanotoxicity as a function of cell metabolism, thus allowing a rational design of next-generation nanomaterials with targeted anticancer properties.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Decagram-Scale Synthesis of Multicolor Carbon Nanodots: Self-Tracking Nanoheaters with Inherent and Selective Anticancer Properties

Mauro

Utzeri

Sciortino

et al. 2022

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

Converting Carbon Dioxide into Carbon Nanotubes by Reacting with Ethane

Yuan,

Huang,

Hwang

et al. 2024

Angewandte Chemie

View full text Add to dashboard Cite

The urgency to mitigate environmental impacts from anthropogenic CO2 emissions has propelled extensive research efforts on CO2 reduction. The current work reports a novel approach involving transforming CO2 and ethane into carbon nanotubes (CNTs) using earth‐abundant metals (Fe, Co, Ni) at 750 °C. This route facilitates long‐term carbon storage via generating high‐value CNTs and produces valuable syngas with adjustable H2/CO ratios as byproducts. Without CO2, direct pyrolysis of ethane undergoes rapid deactivation. The participation of CO2 not only enhances the durability of the catalyst, but also contributes about 30% of the CNTs production, presenting a viable solution to CO2 challenges. The CNT morphology depends on the catalyst used. Co‐ and Ni‐based catalysts produce CNT with a 20 nm diameter and micrometer length, whereas Fe‐based catalysts yield bamboo‐like structures. This work represents a pioneering effort in utilizing CO2 and ethane for CNT production with potential environmental and economic benefits.

show abstract