Sulfur-Doped Wood-derived Porous Carbon for Optimizing Electromagnetic Response Performance

Nanoscale ◽  
2021 ◽  
Author(s):  
Haihua Hu ◽  
Yixing Li ◽  
Tong Gao ◽  
Siyu Yan ◽  
Shiting Wu ◽  
...  

Bio-mass materials have been selected as one of the advanced electromagnetic (EM) functional materials due to its natural porous framework for dynamically and flexibly optimizing the EM response property. Herein,...

Author(s):  
Francesca P. A. Fabbiani

High pressure has become an indispensable research tool in the quest for novel functional materials. High-pressure crystallographic studies on non-porous, framework materials based on coordination compounds are markedly on the rise, enabling the unravelling of structural phenomena and taking us a step closer to the derivation of structure–property relationships.


2018 ◽  
Vol 5 (1) ◽  
pp. 171662 ◽  
Author(s):  
Bin Feng ◽  
Wenzhong Shen ◽  
Liyi Shi ◽  
Shijie Qu

Owing to the unique microporous structure and high specific surface area, porous carbon could act as a good carrier for functional materials. In this paper, polyacrylonitrile (PAN)-based porous carbon materials (PPC-0.6-600, PPC-0.8-600, PPC-0.6-800 and PPC-0.8-800) were prepared by heating KOH at 600°C and 800 o C for the removal of Cr(VI) from aqueous solution. The adsorbent was characterized by the techniques of Fourier transform infrared spectroscopy (FT-IR), elementary analysis, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and N 2 adsorption techniques. The results showed that the adsorption capacity increased with decreasing pH value of the initial solution. The adsorption capacity of Cr(VI) on PPC-0.8-800 was much greater than that on other materials, and maximum adsorption capacity were calculated to be 374.90 mg g −1 . Moreover, PPC-0.8-800 had superior recyclability for the removal of Cr(VI) from wastewater, about 82% of its initial adsorption capacity was retained even after five cycles. The result of kinetic simulation showed that the adsorption of Cr(VI) on the PAN-based porous carbon could be described by pseudo-second-order kinetics. The adsorption process was the ionic interaction between protonated amine groups of PPC and HCrO 4 - ions.


2021 ◽  
Vol 7 (1) ◽  
pp. 22
Author(s):  
Jochen Bahner ◽  
Nicolas Hug ◽  
Sebastian Polarz

Porosity is of high importance for functional materials, as it allows for high surface areas and the accessibility of materials. While the fundamental interplay between different pore sizes and functionalities is quite well understood, few studies on gradually changing properties in a material exist. To date, only a few examples of such materials have been synthesized successfully. Herein, we present a facile method for synthesizing macroscopic carbon aerogels with locally changing pore sizes and functionalities. We used ultracentrifugation to fractionate differently functionalized and sized polystyrene nanoparticles. The assembly into gradient templates was conducted in a resorcinol–formaldehyde (RF) sol, which acted as a liquid phase and carbon precursor. We show that the modification of nanoparticles and a sol–gel precursor is a powerful tool for introducing dopants (sulfur and phosphorous) and metal nanoparticles (e.g., Ni) into gradient porous carbons formed during the carbonization of the RF sol. Understanding the underlying interactions between particles and precursors will lead to a plethora of possibilities in the material design of complex functionally graded materials. We showed this by exchanging parts of the template with magnetite–polystyrene composites as templating nanoparticles. This led to the incorporation of magnetite nanoparticles in the formed gradient porous carbon aerogels. Finally, gradually increasing concentrations of magnetite were obtained, ultimately leading to macroscopic carbon aerogels with locally changing magnetic properties, while the graded porosity was maintained.


2021 ◽  
Author(s):  
Xiao-Sa Zhang ◽  
Hong-Tian Zhao ◽  
Yu Liu ◽  
Wenze Li ◽  
Ai-Ai Yang ◽  
...  

Metal–organic frameworks (MOFs) have recently emerged as a type of uniformly and periodically atom-distributed precursor and efficient self-sacrificial template to fabricate hierarchical porous-carbon-related nanostructured functional materials. In this work, we...


Author(s):  
Yoichi Ishida ◽  
Hideki Ichinose ◽  
Yutaka Takahashi ◽  
Jin-yeh Wang

Layered materials draw attention in recent years in response to the world-wide drive to discover new functional materials. High-Tc superconducting oxide is one example. Internal interfaces in such layered materials differ significantly from those of cubic metals. They are often parallel to the layer of the neighboring crystals in sintered samples(layer plane boundary), while periodically ordered interfaces with the two neighboring crystals in mirror symmetry to each other are relatively rare. Consequently, the atomistic features of the interface differ significantly from those of cubic metals. In this paper grain boundaries in sintered high-Tc superconducting oxides, joined interfaces between engineering ceramics with metals, and polytype interfaces in vapor-deposited bicrystal are examined to collect atomic information of the interfaces in layered materials. The analysis proved that they are not neccessarily more complicated than that of simple grain boundaries in cubic metals. The interfaces are majorly layer plane type which is parallel to the compound layer. Secondly, chemical information is often available, which helps the interpretation of the interface atomic structure.


2020 ◽  
Vol 11 (48) ◽  
pp. 7603-7624
Author(s):  
Ismail Altinbasak ◽  
Mehmet Arslan ◽  
Rana Sanyal ◽  
Amitav Sanyal

This review provides an overview of synthetic approaches utilized to incorporate the thiol-reactive pyridyl-disulfide motif into various polymeric materials, and briefly highlights its utilization to obtain functional materials.


1985 ◽  
Vol 28 (4) ◽  
pp. 539-547 ◽  
Author(s):  
Michael A. Primus ◽  
Gary Thompson

An operant conditioning discrimination paradigm was evaluated in terms of relationships between response behavior of young children and two stimulus components of the paradigm, the discriminative stimulus (DS) and the reinforcing stimulus (RS). Experiment I measured response performance in normal 1-year-old subjects as a function of differences in intensity and/or complexity among three DSs. Results showed no significant differences in conditioning rate, habituation, or consistency of the conditioned response relative to variable properties of the DS. Experiment II examined response performance of normal 2-year-old children as a function of two modifications in the RS, reinforcement schedule and reinforcement novelty. Subjects reinforced on a variable-ratio schedule of intermittent reinforcement and subjects reinforced on a 100% schedule demonstrated equivalent response habituation and consistency. In the second part of the experiment, subjects receiving novel RSs showed significantly greater response recovery than subjects reinforced with familiar RSs. Comparison of normal 1- and 2-year-old children revealed similar rates of conditioning and response consistency. However, 2-year-olds habituated more rapidly than 1-year-olds.


1969 ◽  
Vol 68 (1, Pt.1) ◽  
pp. 147-154 ◽  
Author(s):  
Roger W. Buddington ◽  
Frederick A. King ◽  
Lamar Roberts

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