Block copolymer-based porous carbon fibers
Zhengping Zhou1, Tianyu Liu1, Assad U Khan1
1Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA.
Science Advances
|February 13, 2019
Summary
We developed a new method to create porous carbon fibers (PCFs) with controlled pores. These advanced PCFs offer significantly improved performance for electrochemical energy storage applications.
Area of Science:
- Materials Science
- Electrochemistry
- Nanotechnology
Background:
- Carbon fibers offer high surface area but controlling their porosity is difficult.
- Conventional methods using sacrificial additives yield poorly defined pores.
- Block copolymer microphase separation presents an alternative synthesis strategy.
Purpose of the Study:
- To synthesize porous carbon fibers (PCFs) with well-controlled bimodal porosity.
- To investigate the electrochemical properties of these novel PCFs.
- To establish PCFs as a new material for energy storage.
Main Methods:
- Utilizing block copolymer microphase separation of poly(acrylonitrile-block-methyl methacrylate).
- Direct conversion of the block copolymer to nitrogen and oxygen dual-doped PCFs via pyrolysis.
- Characterization of pore structure (mesopores ~10 nm, micropores ~0.5 nm) and electrochemical performance.
Main Results:
- Achieved PCFs with precisely controlled mesopores and micropores.
- Synthesized dual-doped (N, O) PCFs without additional precursors.
- Demonstrated ultrahigh capacitance (66 μF cm⁻²) and reduced ion transport resistance.
Conclusions:
- Block copolymer precursor approach revolutionizes PCF synthesis.
- PCFs exhibit superior electrochemical properties compared to activated carbon.
- PCFs represent a promising new platform for electrochemical energy storage.
More Related Videos
10:53Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
14.6K
06:02Disentangling High Strength Copolymer Aramid Fibers to Enable the Determination of Their Mechanical Properties
Published on: September 1, 2018
7.5K
Related Concept Videos
01:24Characteristics and Nomenclature of Copolymers
3.3K
Copolymers are the products obtained from the polymerization of multiple monomer species. So, in a polymer chain itself, there can be multiple repeating units that come from different monomers. The process of synthesizing a polymer from different monomer species is called copolymerization. When two monomers are involved, the polymer is known as a bipolymer. Polymers with three and four monomers are termed terpolymers and quaterpolymers, respectively. Figure 1 depicts the copolymerization of...
3.3K
01:14The Carbon Cycle
43.7K
Carbon is the basis of all organic matter on Earth, and is recycled through the ecosystem in two primary processes: one in which carbon is exchanged among living organisms, and one in which carbon is cycled over long periods of time through fossilized organic remains, weathering of rocks, and volcanic activity. Human activities, including increased agricultural practices and the burning of fossil fuels, has greatly affected the balance of the natural carbon cycle.
43.7K
01:12Carbon Skeletons
114.9K
Life on Earth is carbon-based, as all macromolecules that make up living organisms contain carbon atoms. All organic compounds have a carbon backbone. Each carbon atom is tetravalent and can bond with four other atoms, making it an extraordinarily flexible component of biological molecules. Because carbon’s valence electrons are stable, it rarely becomes an ion. As the carbon chain increases in length, structural modifications such as ring structures, double bonds, and branching side...
114.9K
01:48Classification of Skeletal Muscle Fibers
59.5K
Skeletal muscles continuously produce ATP to provide the energy that enables muscle contractions. Skeletal muscle fibers can be categorized into three types based on differences in their contraction speed and how they produce ATP, as well as physical differences related to these factors. Most human muscles contain all three muscle fiber types, albeit in varying proportions.
Slow-Twitch Muscle Fibers
Slow oxidative, muscle fibers appear red due to large numbers of capillaries and high levels of...
Slow-Twitch Muscle Fibers
Slow oxidative, muscle fibers appear red due to large numbers of capillaries and high levels of...
59.5K
01:24Carbonation Shrinkage
473
Atmospheric CO2 penetrates the concrete's pores and, in the presence of moisture, forms carbonic acid, which then reacts with calcium hydroxide in the hydrated cement, forming calcium carbonate. This process reduces the concrete's volume and is termed carbonation shrinkage.
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction...
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction...
473
01:22Block Diagram Reduction
553
The process of deriving the transfer function of a control system often involves reducing its block diagram to a single block. This simplification can be achieved through a series of strategic operations, including relocating branch points and comparators. These operations preserve the overall function of the system while allowing for easier manipulation and combination of blocks.
The first step in this process is the identification and relocation of a branch point. A branch point, where a...
The first step in this process is the identification and relocation of a branch point. A branch point, where a...
553