Energy storage capabilities of nitrogen-enriched pyropolymer nanoparticles fabricated through rapid pyrolysis

Yun, Young Soo,Kim, Yu Hyun,Song, Min Yeong,Kim, Na Rae,Ku, Kyojin,An, Ji Su,Kang, Kisuk,Choi, Hyoung Jin,Jin, Hyoung-Joon Elsevier 2016 Journal of Power Sources Vol.331 No.-

<P><B>Abstract</B></P> <P>Nanostructured pyropolymers contain significant amounts of redox-active heteroatoms, have high specific surface areas, and a defective carbon microstructure, indicating good potential for pseudocapacitive charge storage. In this study, nitrogen-enriched pyropolymer nanoparticles (N-PNs-50) are fabricated from polyaniline nanotubes through rapid pyrolysis at 50 °C min<SUP>−1</SUP>. N-PNs-50 exhibit a nitrogen content of 9.8 wt%, a high specific surface area of 875.8 m<SUP>2</SUP> g<SUP>−1</SUP>, and an amorphous carbon structure with an I<SUB> <I>D</I> </SUB>/I<SUB> <I>G</I> </SUB> intensity ratio of 0.95. These unique characteristics lead to good electrochemical performances, in which reversible capacities of 660 and 255 mAh g<SUP>−1</SUP> are achieved for Li-ion and Na-ion storage, respectively, with favorable voltage characteristics (<1.5 V for Li-ions and <1.2 V for Na-ions). This study provides a more feasible production method for nitrogen-doped pyropolymers and their practicable electrochemical performances for use as an anode in energy storage devices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nanostructured pyropolymers (N-PNs-50) were fabricated by rapid pyrolysis. </LI> <LI> N-PNs-50 exhibited a nitrogen content of 9.8 wt% and amorphous carbon structure. </LI> <LI> N-PNs-50 exhibited a high specific surface area of 875.8 m<SUP>2</SUP> g<SUP>−1</SUP>. </LI> <LI> 660 and 255 mAh g<SUP>−1</SUP> were achieved for Li-ion and Na-ion storage, respectively. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Nitrogen-enriched pyropolymer nanoparticles (N-PNs-50) were fabricated from polyaniline nanotubes through rapid pyrolysis at 50 °C min<SUP>−1</SUP>, showing superior electrochemical performances.</P> <P>[DISPLAY OMISSION]</P>

Hierarchically nanoporous pyropolymer nanofibers for surface-induced sodium-ion storage

Yoon, Hyeon Ji,Lee, Min Eui,Kim, Na Rae,Yang, Seung Jae,Jin, Hyoung-Joon,Yun, Young Soo Pergamon Press 2017 Electrochimica Acta Vol. No.

<P><B>Abstract</B></P> <P>Surface-driven charge storage materials based on both electrochemical double layer (EDL) formation and pseudocapacitive behavior can deliver high energy and power capabilities with long-lasting cycling performance. On the other hand, the electrochemical performance is strongly dependent on the material properties, requiring sophisticated electrode design with a high active surface area and a large number of redox-active sites. In this study, hierarchically nanoporous pyropolymer nanofibers (HN-PNFs) were fabricated from electrospun polyacrylonitrile nanofibers by simple heating with KOH. The HN-PNFs have a hierarchically nanoporous structure and an exceptionally high specific surface area of 3,950.7m<SUP>2</SUP> g<SUP>−1</SUP> as well as numerous redox-active heteroatoms (C/O and C/N ratio of 10.6 and 16.8, respectively). These unique material properties of HN-PNFs resulted in high reversible Na-ion capacity of ∼292mAhg<SUP>−1</SUP> as well as rapid kinetics and stable cycling performance in the cathodic potential range (1-4.5V vs. Na<SUP>+</SUP>/Na). Furthermore, energy storage devices based on HN-PNFs showed a remarkably high specific energy of ∼258 Wh kg<SUP>−1</SUP> at ∼245Wkg<SUP>−1</SUP> as well as a high specific power of ∼21,500Wkg<SUP>−1</SUP> at ∼78 Wh kg<SUP>−1</SUP>, with long and stable cycling behaviors over 2,000 cycles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Hierarchically nanoporous pyropolymer nanofibers (HN-PNFs) were fabricated. </LI> <LI> HN-PNFs have a high specific surface area of ∼3,950m<SUP>2</SUP> g<SUP>−1</SUP> and numerous heteroatoms. </LI> <LI> HN-PNFs exhibit high capacities of ∼292mAhg<SUP>−1</SUP> and great rate/cycling performances. </LI> <LI> High energy (258Whkg<SUP>−1</SUP>) and high power (21,500Wkg<SUP>−1</SUP>) are achieved. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Hierarchically nanoporous pyropolymer nanofibers (HN-PNFs) fabricated from electrospun polyacrylonitrile nanofibers by simple heating with KOH exhibited high electrochemical performance for Na-ion storage.</P> <P>[DISPLAY OMISSION]</P>

알칼리 이온 저장을 위한 탄소/파이로폴리머 전극 소재

현종찬(Jong Chan Hyun),최연화(Yeonhua Choi),윤영수(Young Soo Yun) 한국세라믹학회 2022 세라미스트 Vol.25 No.1

Carbon materials have large numbers of redox-active sites for alkali-ion storage, such as Stone-Wales, vacancy, edge, and pseudo-edge defect sites as well as extrinsic defects. The topological defects can be a redox host in anodic voltage regions, while the extrinsic defects can store alkali ions in a cathodic voltage range. Therefore, carbon materials can be a great candidate for both anode and cathode for alkali ion batteries. In this study, alkali ion storage behaviors of different carbon materials, highly defective graphene-based nanosheet (GNS), well-ordered graphite nanoplate (GNP), hard carbon series samples, and nanoporous pyropolymers which are a kind of carbon materials including numerous defects, are reviewed, and their potentials as both anode and cathode for alkali ion batteries are discussed.

Nanoporous pyropolymer nanosheets fabricated from renewable bio-resources for supercapacitors

최재원,김나래,진형준,윤영수 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.43 No.-

In this study, nanoporous pyropolymer nanosheets (NPNs) were fabricated from Citreae peels by simplepyrolysis with potassium hydroxide. The NPNs have a high specific surface area of 1522 m2[4TD$DIF] g 1,numerous nanometer-scale pores, a high electrical conductivity of 210 S cm 1, and a large amount ofoxygen (19.4 wt.%) and nitrogen (3.4 wt.%) heteroatoms. These unique material properties lead to goodelectrochemical performance of NPNs as supercapacitor electrodes; they showed high specificcapacitance of 330 F g 1, good rate capabilities (221 F g 1 to 60 A g 1), and stable cyclic performancefor more than 20,000 cycles. This study provides information on the simple fabrication of sustainable andfunctional carbon-based materials containing numerous nanopores and redox-active heteroatoms. Inaddition, these materials demonstrate superior electrochemical performances as electrodes forsupercapacitors.

Nanoporous pyropolymer nanosheets fabricated from renewable bio-resources for supercapacitors

Choi, J.,Kim, N.R.,Jin, H.J.,Yun, Y.S. Korean Society of Industrial and Engineering Chemi 2016 Journal of industrial and engineering chemistry Vol.43 No.-

<P>In this study, nanoporous pyropolymer nanosheets (NPNs) were fabricated from Citreae peels by simple pyrolysis with potassium hydroxide. The NPNs have a high specific surface area of 1522 m(2) g(-1), numerous nanometer-scale pores, a high electrical conductivity of 210 S cm(-1), and a large amount of oxygen (19.4 wt.%) and nitrogen (3.4 wt.%) heteroatoms. These unique material properties lead to good electrochemical performance of NPNs as supercapacitor electrodes; they showed high specific capacitance of 330 F g(-1), good rate capabilities (221 F g(-1) to 60 A g(-1)), and stable cyclic performance for more than 20,000 cycles. This study provides information on the simple fabrication of sustainable and functional carbon-based materials containing numerous nanopores and redox-active heteroatoms. In addition, these materials demonstrate superior electrochemical performances as electrodes for supercapacitors. (C) 2016 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.</P>

Fallen-leaf-derived microporous pyropolymers for supercapacitors

안홍주,김나래,송민영,윤영수,진형준 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.45 No.-

In this study, microporous pyropolymers (GL-AMPs), a carbon-based material, were fabricated fromginkgo leaves by simple pyrolysis with KOH, followed by acid treatment. The GL-AMPs were mainlycomposed of aromatic hexagonal carbon layers, which were not well stacked, and contained many redox-active heteroatoms such as oxygen and nitrogen. In addition, the GL-AMPs had a high specific surface areaof1348.4 m2 g 1 with numerous ultramicropores (<0.7 nm). These unique material characteristics ledto a significantly high specific capacitance of731 F g 1, high rate capabilities, and stable cyclingperformance over 1000 cycles in a redox-mediated aqueous electrolyte.

Fallen-leaf-derived microporous pyropolymers for supercapacitors

An, H.J.,Kim, N.R.,Song, M.Y.,Yun, Y.S.,Jin, H.J. Korean Society of Industrial and Engineering Chemi 2017 Journal of industrial and engineering chemistry Vol.45 No.-

<P>In this study, microporous pyropolymers (GL-AMPs), a carbon-based material, were fabricated from ginkgo leaves by simple pyrolysis with KOH, followed by acid treatment. The GL-AMPS were mainly composed of aromatic hexagonal carbon layers, which were not well stacked, and contained many redox-active heteroatoms such as oxygen and nitrogen. In addition, the GL-AMPS had a high specific surface area of similar to 1348.4 m(2)g(-1) with numerous ultramicropores (<0.7 nm). These unique material characteristics led to a significantly high specific capacitance of similar to 731 Fg(-1), high rate capabilities, and stable cycling performance over 1000 cycles in a redox-mediated aqueous electrolyte. (C) 2016 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.</P>

High-performance Li-ion hybrid supercapacitors based on microporous pyropolymer nanoplates and orthorhombic Nb2O5 nanocomposites

이민의,조세연,윤현지,윤영수,진형준 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.57 No.-

In this study, high-performance Li-ion hybrid supercapacitors (LIHSs) were realized by the sophisticated design of nanostructured electrode pairs demonstrating both energy and kinetic balance. Microporous pyroprotein nanoplates (M-PNPs) were fabricated by a controlled pyrolysis process using potassium hydroxide, to achieve high electrochemical performance in the cathodic voltage region of 2.0-4.5 V vs. Li+/Li. M-PNP/T-Nb2O5 nanocomposites obtained by introducing niobium oxide (T-Nb2O5) nanoparticles on the surface of M-PNP also showed outstanding Li-ion storage kinetics in the anodic voltage range of 1.0-2.0 vs. Li+/Li. The LIHSs based on M-PNP and M-PNP/T-Nb2O5 nanocomposite samples used as the cathode and anode pair, respectively, exhibited a high specific energy of ~47.5 W h kg-1 at ~280.0 W kg-1 and a high specific power of ~10,000 W kg-1 at ~22.3 W h kg-1 with excellent cycling stability over 30,000 cycles.

High-performance Li-ion hybrid supercapacitors based on microporous pyropolymer nanoplates and orthorhombic Nb₂O₅ nanocomposites

Lee, Min Eui,Cho, Se Youn,Yoon, Hyeon Ji,Yun, Young Soo,Jin, Hyoung-Joon Elsevier 2018 Journal of industrial and engineering chemistry Vol.57 No.-

<P><B>Abstract</B></P> <P>In this study, high-performance Li-ion hybrid supercapacitors (LIHSs) were realized by the sophisticated design of nanostructured electrode pairs demonstrating both energy and kinetic balance. Microporous pyroprotein nanoplates (M-PNPs) were fabricated by a controlled pyrolysis process using potassium hydroxide, to achieve high electrochemical performance in the cathodic voltage region of 2.0–4.5V <I>vs</I>. Li<SUP>+</SUP>/Li. M-PNP/T-Nb<SUB>2</SUB>O<SUB>5</SUB> nanocomposites obtained by introducing niobium oxide (T-Nb<SUB>2</SUB>O<SUB>5</SUB>) nanoparticles on the surface of M-PNP also showed outstanding Li-ion storage kinetics in the anodic voltage range of 1.0–2.0 <I>vs</I>. Li<SUP>+</SUP>/Li. The LIHSs based on M-PNP and M-PNP/T-Nb<SUB>2</SUB>O<SUB>5</SUB> nanocomposite samples used as the cathode and anode pair, respectively, exhibited a high specific energy of ∼47.5Whkg<SUP>−1</SUP> at ∼280.0Wkg<SUP>−1</SUP> and a high specific power of ∼10,000Wkg<SUP>−1</SUP> at ∼22.3Whkg<SUP>−1</SUP> with excellent cycling stability over 30,000 cycles.</P> <P><B>Graphical abstract</B></P> <P>Microporous pyroprotein nanoplates (M-PNPs) with aspect ratios of >100, electrical conductivities of ∼36Scm<SUP>−1</SUP>, specific surface areas of ∼2347.7m<SUP>2</SUP> g<SUP>−1</SUP>, and many redox-active heteroatoms were fabricated from silk protein by a controlled pyrolysis process with potassium hydroxide, and orthorhombic niobium oxide (T-Nb<SUB>2</SUB>O<SUB>5</SUB>) nanoparticles were introduced to the surfaces of M-PNPs. M-PNPs and M-PNPs/T-Nb<SUB>2</SUB>O<SUB>5</SUB> nanocomposites showed high electrochemical performances as cathode and anode, respectively. Moreover, Li-ion hybrid capacitors based on their electrode pairs achieved the high specific energy of ∼47.5Whkg<SUP>−1</SUP> at ∼280.0Wkg<SUP>−1</SUP> and the high specific power of ∼10,000Wkg<SUP>−1</SUP> at ∼22.3Whkg<SUP>−1</SUP> with excellent cycling stability for 30,000 cycles.</P> <P>[DISPLAY OMISSION]</P>