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Article
Publication date: 2 May 2017

Benfu Wang, Decai Ren, Qian Zhang, Xuduo Bai and Xiankai Jiang

This paper aims to investigate the electrochromic (EC) properties of poly(triphenylamine alkyl ether) and poly(triphenylamine aryl ether) in two different electrolyte solution to…

Abstract

Purpose

This paper aims to investigate the electrochromic (EC) properties of poly(triphenylamine alkyl ether) and poly(triphenylamine aryl ether) in two different electrolyte solution to study the resistive switching behaviour of acid-doped poly(triphenylamine alkyl ether).

Design/methodology_appach

By Buchwald–Hartwig coupling reaction, two novel poly[N-p-phenoxy-N-[4-[2-(2-methoxyethoxy)ethoxy]ethoxy]triphenylamineandpoly[N,N-bis(4-phenoxy)]triphenylamine were synthesized from 4-phenoxyaniline and two dibromo aromatic compounds, 1,2-bis[β,β′-(p-bromophenoxy)ethoxy]ethane and bis(4-bromophenyl) ether.

Findings

Poly(triphenylamine alkyl ether) displayed excellent EC characteristics, with a coloration change from a colourless neutral state to light blue and red oxidized states, while poly(triphenylamine aryl ether) showed coloration a change from a colourless neutral state to light blue oxidized state in tetrabutylammonium perchlorate electrolyte solution. Moreover, p-toluenesulfonic acid-doped poly(triphenylamine alkyl ether) exhibited a non-volatile bistable resistive switching behaviour with a high high-conductivity/low-conductivity ratio of up to 104, long retention time exceeding 2.5 × 103 s and the switching threshold voltage was also lower than −2V.

Research limitations/implications

In this paper, the non-volatile bistable resistive switching behaviour of acid-dopedpoly(triphenylamine alkyl ether) was in accordance with the molar ratio of 1:1. The effects of different molar ratios remained to be studied.

Practical implications

Poly(triphenylamine ether)s may find optoelectronic applications as new EC and resistive switching materials.

Originality/value

The effects of alkyl and aryl ether structures in the main chain on the EC and resistive switching behaviour of triphenylamine unit have not yet been reported.

Details

Pigment & Resin Technology, vol. 46 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 6 July 2015

Jiahuan Du, Qiang Li, Chuanli Qin, Xugang Zhang, Zheng Jin and Xuduo Bai

– The purpose of this paper is to develop nitrogen-enriched carbon (NC) with high conductivity and specific capacitance as electrode materials for supercapacitors.

Abstract

Purpose

The purpose of this paper is to develop nitrogen-enriched carbon (NC) with high conductivity and specific capacitance as electrode materials for supercapacitors.

Design/methodology/approach

Graphene oxide (GO) was synthesized by the modified Hummers–Offeman method. NC was synthesized by carbonization of melamine formaldehyde resin/graphene oxide (MF/GO) composites. Supercapacitors based on Ni(OH)2/Co(OH)2 composites as the positive electrode and NC as the negative electrode were assembled. The electrochemical performances of NC and supercapacitors are studied.

Findings

The results show that obtained NC has high nitrogen content. Compared to NC-GO0 without GO, high conductivity and specific capacitance were obtained for NC with GO due to the introduction of layered GO. The presence of pseudocapacitive interactions between potassium cations and the nitrogen atoms of NC was also proposed. When the weight ratio of GO to MF is 0.013:1, the obtained NC-GO3 has the highest specific capacitance of 154.07 F/g due to GO and its highest content of N-6. When the P of the asymmetric supercapacitor with NC-GO3 as the negative electrode is 1,326.70 W/kg, its Cps and Ep are still 23.84 F/g and 8.48 Wh/Kg, respectively. There is only 4.4 per cent decay in Cps of the supercapacitor over 1,000 cycles.

Research limitations/implications

NC is a suitable electrode material for supercapacitors. The supercapacitors can be used in the field of automobiles and can solve the problems of energy shortage and environmental pollutions.

Originality/value

NC based on MF/GO composites with high nitrogen content and conductivity was novel and its electrochemical properties were excellent.

Details

Pigment & Resin Technology, vol. 44 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 7 November 2008

Chuanli Qin, Jin Zheng, Jiang Haijian, Tan Qiang and Bai Xuduo

The aim of the paper is to develop a method to block hydroxyl groups of epoxy acrylate (AAEP) in vinyl ester resin (VER) and to study the influence of modified VER on…

Abstract

Purpose

The aim of the paper is to develop a method to block hydroxyl groups of epoxy acrylate (AAEP) in vinyl ester resin (VER) and to study the influence of modified VER on polyurethane/(VER) interpenetrating polymer network (PU/VER IPN).

Design/methodology/approach

The hydroxyl groups of AAEP in VER were blocked via different methods. Infra‐red spectroscopy was adopted to study the influence of the reagents, reaction temperature and feed molar ratio on the blocking effect of hydroxyl groups and the optimised technological parameters were determined. The PU/VER IPN and PU/modified VER IPN were prepared by simultaneous interpenetrating of VER (mixture of AAEP and butyl methacrylate with the mass ratio of 2/1) or modified VER and synthesised PU in their laboratory. The microstructure, dynamic mechanical properties and mechanical properties of PU/VER IPN and PU/modified VER IPN were compared.

Findings

The results showed that compared to unmodified IPN, because the hydroxyl groups in VER were blocked and no chemical cross‐linked structure existed between the two networks, the modified IPN showed dual‐continuous microsturcture with larger phase domain sizes between 20 and 50 nm. The effect damping temperature range of modified IPN was broadened and its damping performance was improved. The mechanical strength of modified IPNs decreased and their break elongation increased evidently.

Practical implications

The PU/modified VER IPN with excellent damping properties can be used in the applications where reduction of vibration and noise is desired.

Originality/value

The PU/modified VER IPN, in which no chemical cross‐linked structure existed between the two networks, was novel and its damping performance was improved and excellent.

Details

Pigment & Resin Technology, vol. 37 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 5 July 2011

Zheng Jin, Xiaomin Ren, Chuanli Qin, Bohong Li, Shuai Quan and Xuduo Bai

The purpose of this paper is to develop feasible composite electrodes with a long cycle life and large specific capacitance and to investigate optimal ratio between aniline and…

1489

Abstract

Purpose

The purpose of this paper is to develop feasible composite electrodes with a long cycle life and large specific capacitance and to investigate optimal ratio between aniline and activated carbon materials.

Design/methodology/approach

PANI/AC composite electrode materials were synthesised by in situ polymerisation of aniline on activated carbon with ammonium persulphate as oxidant. Hybrid supercapacitors are assembled by putting Ni‐MH battery separator between positive and negative electrodes. The electrochemical performances of PANI/AC composite electrode materials and supercapacitors are studied.

Findings

The results show that the optimal ratio between aniline and activated carbon is 1:1.08. The specific capacitance of polyaniline electrode materials is 956 F g−1. The specific capacitance of supercapacitors is 159.37 F g−1. This result could be attributed to the pseudocapacitive effect of Ni(OH)2. What's more, the activated carbon addition reduced the resistance of polymer electrode materials thus improving the cyclic life.

Research limitations/implications

The supercapacitors can be used in the field of automobiles and can solve the problems of energy shortage and environmental pollutions.

Originality/value

A hybrid supercapacitor, which was immersed in alkaline solution, was assembled by putting Ni‐MH battery separator between two electrodes Ni(OH)2 as positive electrode and polyaniline composites as negative electrode. In the case of alkaline solution, the capacitive performance of hybrid supercapacitor was improved and excellent.

Details

Pigment & Resin Technology, vol. 40 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 11 September 2009

Dongyu Zhao, Shuhong Wang, Jie Wu, Xuduo Bai and Qingquan Lei

The purpose of this paper is to study a new method with which multi‐walled carbon nanotubes (MWNTs) can be dispersed and aligned in low density polyethylene (LDPE) for improving…

Abstract

Purpose

The purpose of this paper is to study a new method with which multi‐walled carbon nanotubes (MWNTs) can be dispersed and aligned in low density polyethylene (LDPE) for improving its mechanical properties.

Design/methodology/approach

Dispersion and alignment of MWNTs in LDPE matrix are enhanced by ultrasonic vibration, solution casting and melt mixing and flow moulding method. The properties of the composite are characterised using scanning electron microscopy, tensile testing machine and the Izod impact testing machine.

Findings

It is found that MWNTs in LDPE achieve some dispersion and alignment resulting in improvement in LDPE's strength and toughness.

Practical implications

Polymer/CNTs nanocomposites are expected to have good process ability of the polymers and high mechanical and functional properties of the CNTs. Enhancing dispersion and alignment of MWNTs in the polymer matrix will promote and expand the applications and development of polymer/MWNTs nanocomposites.

Originality/value

The method that enhances MWNTs dispersion and alignment in LDPE matrix provides a new way for alignment of other CNTs in polymer matrix.

Details

Pigment & Resin Technology, vol. 38 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 3 July 2009

Chuanli Qin, Xuduo Bai, Geping Yin, Yuxi Liu, Zheng Jin and Haijun Niu

The purpose of this paper is to show how to obtain a supercapacitor with high specific power (P) and high specific energy (Ep) simultaneously.

1551

Abstract

Purpose

The purpose of this paper is to show how to obtain a supercapacitor with high specific power (P) and high specific energy (Ep) simultaneously.

Design/methodology/approach

The carbon aerogels are obtained by ambient pressure drying method instead of supercritical drying method and carbon aerogels/Ni(OH)2 composites are prepared by in situ polymerisation. A series of asymmetric supercapacitors based on carbon aerogels/Ni(OH)2 composites as positive electrode and activated carbon as negative electrode, respectively, are assembled. The electrochemical performances of carbon aerogels/Ni(OH)2 composites and supercapacitors are studied.

Findings

The results show that the specific capacitance (CP) of carbon aerogels/Ni(OH)2 composites is 584 F/m2. The working potential of supercapacitors could be increased to 1.6V. When the mass ratio of carbon aerogels and Ni(OH)2 is 3:7, the mass ratio of positive electrode and negative electrode is 1:1, the EP and P of the supercapacitor is higher than 10.5 Wh/kg and 578 W/kg, respectively, when the current varies from 50 mA to 100 mA and the attenuation ratio of CP is only 8.3 per cent after 10,000 cycles at 100 mA.

Practical implications

The supercapacitors can be used in the field of automobile engineering and can solve the problems of energy shortage and environmental pollutions.

Originality/value

The supercapacitor based on carbon aerogels/Ni(OH)2 composites as positive electrode and activated carbon as negative electrode is novel and the synthetic properties of the supercapacitor are excellent.

Details

Pigment & Resin Technology, vol. 38 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 24 May 2011

Zheng Jin, Yuxi Liu, Xuduo Bai, Xiaomin Ren, Chuanli Qin and Yunhua Wang

The purpose of this paper is to develop a facile method to synthesise nitrogen‐doped carbon aerogels to increase the capacity of supercapacitors.

Abstract

Purpose

The purpose of this paper is to develop a facile method to synthesise nitrogen‐doped carbon aerogels to increase the capacity of supercapacitors.

Design/methodology/approach

Nitrogen‐doped carbon aerogels are prepared as electrode materials through sol‐gel method, using resorcinol, formaldehyde and aniline as raw materials. A series of symmetric supercapacitors are assembled by putting Ni‐MH battery separator between two carbon aerogels electrodes. The electrochemical performances of carbon aerogels and supercapacitors are studied.

Findings

The results show that the optimal molar percentage of aniline in the total molar ratio of resorcinol and aniline is 15 per cent, the mass specific capacitance of which is supposed to be about three times that of RF carbon aerogels. This result could be attributed to the pseudocapacitive effect of nitrogen heteroatoms. Moreover, the nitrogen‐doped carbon aerogels are found to exhibit lower charge transfer resistance at the electrolyte/carbon aerogels interface and lower Warburg impedance.

Practical implications

The supercapacitors can be used in the field of automobile and can solve the problems of energy shortage and environmental pollutions.

Originality/value

For the first time, nitrogen‐doped carbon aerogels are prepared through sol‐gel method, using resorcinol, formaldehyde and aniline as raw materials.

Details

Pigment & Resin Technology, vol. 40 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 7 September 2015

Qiang Li, Jiahuan Du, Xugang Zhang, Chuanli Qin, Zheng Jin and Xuduo Bai

The purpose of this paper is to develop porous nitrogen-enriched carbon (NC-U) with high nitrogen concentration and high specific capacitance (Cpe) as the electrode material for…

Abstract

Purpose

The purpose of this paper is to develop porous nitrogen-enriched carbon (NC-U) with high nitrogen concentration and high specific capacitance (Cpe) as the electrode material for supercapacitors.

Design/methodology/approach

NC-U was obtained by carbonization of polyvinylpyrrolidone/melamine formaldehyde resin (PVP/MF) with different contents of urea. In comparison, NC-K was also prepared by the KOH activation method. A series of asymmetric supercapacitors with NC as a negative electrode was assembled. The composition, microstructure and electrochemical properties of NC and their supercapacitors were studied.

Findings

The results show that NC-U shows irregular particles with a porous honeycomb structure. High Cpe was obtained for urea-treated NC-U because of the improvement of nitrogen, conductivity and specific surface area (S BET ). NC-U50 with 13.15 per cent at nitrogen has the highest Cpe of 148.53 F/g because of the highest concentration of N-6 and N-5. NC-K with higher S BET has lower Cpe than NC-U50 because of its lower nitrogen concentration. When the specific power of the supercapacitor with NC-U50 as a negative electrode is 1,565.56 W/kg, its specific energy is still 4.35 Wh/kg. There is only 5.9 per cent decay in Cpe over 1,000 cycles.

Research limitations/implications

NC-U is a suitable electrode material for supercapacitors, which can be used in the field of electric vehicles to solve the problems of energy shortage and environmental pollutions.

Originality/value

Porous NC-U based on PVP/MF/urea composites with high nitrogen concentration and Cpe is novel, and it owns good electrochemical properties.

Details

Pigment & Resin Technology, vol. 44 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Content available
Article
Publication date: 4 January 2013

Peter Greenwood

75

Abstract

Details

Pigment & Resin Technology, vol. 42 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

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