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The pendent thiol group grafed poly(3,4-proplenedioxythiophene) hollow nanofiber for electrochemical sensing
Materials Letters 263 (2020) 127206
Contents lists available at ScienceDirect
Materials Letters journal homepage: www.elsevier.com/locate/mlblue
The pendent thiol group grafed poly(3,4-proplenedioxythiophene) hollow nanofiber for electrochemical sensing Ruanye Zhang, Mihray Abdulla, Ruxangul Jamal, Yi Ge, Wenli Zhang, Zongna Yu, Yinqiang Yan, Yingcheng Liu, Tursun Abdiryim Key Laboratory of Petroleum and Gas Fine Chemicals, Educational Ministry of China, School of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, People’s Republic of China
a r t i c l e
i n f o
Article history: Received 21 October 2019 Received in revised form 24 November 2019 Accepted 20 December 2019 Available online 20 December 2019 Keywords: Microstructure Hollow nanofibers Thiol group PEDOT Sensors
a b s t r a c t The pendent thiol group grafed poly(3,4-proplenedioxythiophene) (PProDOT-(MeSH)2) hollow nanofibers (HNFs) were prepared via surfactant-assisted method of cetyltrimethyl ammonium bromide (CTAB), and the influence of CTAB concentration on the morphology and electrochemical performance of PProDOT(MeSH)2 were investigated. The physical and chemical properties of PProDOT-(MeSH)2 HNFs were studied by FT-IR, UV–vis, XRD, SEM, TEM and the electrocatalytic activity were evaluated by detecting paracetamol using differential pulse voltammetry (DPV) techniques. The results showed that the PProDOT-(MeSH)2 HNFs in 0.009 M CTAB exhibited a much better electrocatalytic performance. Ó 2019 Published by Elsevier B.V.
1. Introduction One-dimensional conducting polymers nanofibers possess high specific surface area, abundant active sites and high conductivity etc. that endow them with improved performances for application such as chemical sensors [1,2]. PEDOT-based conductive nanomaterials are widely used in biosensors due to their excellent performance. However, the molecular recognition effect of conductive polymers such as PEDOT is not obvious, which weakens their applications in biosensor. Accordingly, introducing proper functional groups (such as –COOH, –NH2, –OH, –SH, etc.) into the PEDOT skeleton can be used as novel electrochemical sensing materials due to the special adsorption and bonding interactions among these functional groups and small biological or drug molecules [3,4]. Here we report a facile chemical route to prepare HNFs of PProDOT-(MeSH)2 under ambient conditions using chemical oxidation polymerization. The pendent thiol groups grafed PProDOT HNFs can significantly improve the electrochemical sensing ability by virtue of their unique electronic transmission channels, excellent molecular recognition ability and unique electrocatalytic properties. Electrolyte is easier to enter the hollow cavity of HNFs, and the pendent thiol group in the polymer also can produce
E-mail addresses: [email protected] (R. Jamal), [email protected] (T. Abdiryim) https://doi.org/10.1016/j.matlet.2019.127206 0167-577X/Ó 2019 Published by Elsevier B.V.
strong non-covalent force with the analytes, which can significantly improve the sensitivity of the sensor. Paracetamol was detected by DPV systematically to research the relationship between the structure and the properties of the polymers. The results showed that the uniform PProDOT-(MeSH)2 HNFs in 0.009 M CTAB exhibits the best electrochemical properties, which indicated that the pendent functional groups grafted polymers HNFs may hold great promise for the design of electrochemical sensors for practical application.
2. Experimental 131 mg (0.009 M) CTAB dissolved in 20 mL CHCl3 and ultrasound for 10 min, then 10 mL of CHCl3 containing 20 mg ProDOT-(MeSH)2 monomer were added to the solution ultrasound for 15 min, and stirred for 30 min under 0 °C. Finally, 10 mL of CHCl3 containing 100 mg of FeCl3 were dropped into the above suspension, stirred at room temperature for 24 h. The products were centrifuged and washed with chloroform, methanol, water, and then dried. The obtained polymer were denoted as PProDOT(MeSH)2 (CTAB, 0.009 M). The detailed description of synthesis of the monomer and concentration of CTAB (Table S1) for polymers are provided in the SI. And, the preparation modified electrodes are also presented in the SI.
R. Zhang et al. / Materials Letters 263 (2020) 127206
3. Results and discussion The microstructure of the as-prepared PProDOT-(MeSH)2 samples in CHCl3 system with different concentration of CTAB were investigated by SEM and TEM (Fig. 1A). As shown in Fig. 1a and f, the polymer without added CTAB shows patch network structure. From Fig. 1b, g, it can be clearly seen that the polymer have irregular structure with a small part of the nanorods in 0.005 M CTAB. While the polymer present a uniform fibrous shape with the diameter of ~50–80 nm. Form the TEM images of Fig. 1h, the hollow structure of the polymer fiber can be clearly judged from the shadow thickness of the polymer. The appearance of hollow fibrous morphology is due to the formation of fibers or rod micelles by self-assembly of surfactant CTAB. Firstly, at a certain concentration, CTAB self-assembles into fibrous micelles. When monomers are added, due to the weak acidity of the thiol groups of ProDOT-(MeSH)2, they can attract each other with the polar end groups of CTAB, so the monomers are uniformly coated on the micelles of CTAB and the polymer film is formed when
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the oxidant of FeCl3 was added. Finally, polymer HNFs were obtained when the CTAB soft template was removed. A simple diagram of polymer HNFs is shown in the Fig. 1(B). After the amount of CTAB reaches a certain level (0.014 M), the morphology of the initial fiber began to change obviously (Fig. 1d and i). Combined with Fig. 1c and d, it is clear seen that blocks structure and inhomogeneity fiber begin to appear in polymer fibers. It also can be seen from the Fig. 1h and i that the diameter of polymer nanofibers increases obviously and the accumulation is more serious. When the concentration of CTAB is up to 0.018 M, the structure of tubular, granular, and few flaky are co-existed in (Fig. 1j). This may be caused by the excessive amount of CTAB, which destroys the action of the surfactant to form tubular micelles. Fig. 2(a) gives the FT-IR spectra of PProDOT-(MeSH)2. All polymers have similar vibration bands appeared at around 3300–3640, ~2921, ~1659, ~1475, ~1359, ~1048 and ~847 cm 1 which are from thiophene ring, while the broad peaks at 3300–3640 cm 1 for all samples can be assigned to S-H vibration
Fig. 1. (A) SEM and TEM images of PProDOT-(MeSH)2 in different concentrations of CTAB, (a) 0.0 M CTAB; (b) 0.005 M CTAB; (c) 0.009 M CTAB; (b) 0.014 M CTAB; (e) 0.018 M CTAB; (B) Schematic diagram of hollow nanofiber formation.
Fig. 2. (a) FT-IR; (b) UV–Vis; (c) XRD patterns of PProDOT(MeSH)2 in different concentrations of CTAB.
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R. Zhang et al. / Materials Letters 263 (2020) 127206
Fig. 3. (a) EIS different modified GCEs in 0.1 M H2SO4 aqueous solution; (b) DPV response curves of different modified GCEs;
[5]. Fig. 2(b) shows the UV–vis spectra of PProDOT-(MeSH)2. The polymers from 0.005 M, 0.009 M and 0.014 M CTAB display broad absorption peaks at ~425–620 nm with several shoulders, and they are ascribed to the p-p* transition of the thiophene ring [6]. However, the polymers from 0 M and 0.018 M CTAB have no obvious peaks at ~425–620 nm implying the low conjugation degree of polymer. The XRD patterns (Fig. 2(c)) show that all polymers have similar broad diffraction peaks (2h = 15°~20°) and sharp diffraction peaks (2h = 33.4°, 35.8°, 49.5°, 54°), which are from the interchain planar stacking of polymer chains and the FeC14 1 doping agent, respectively [7]. It is obvious that diffraction peak of polymer HNFs (from 0.009 M CTAB) is higher than others, indicating that polymer HNFs have relatively high crystallization degree. The electrochemical behavior of the samples modified electrodes were investigated by EIS and DPV. As shown in Fig. 3(a), the polymer HNFs (from 0.009 M CTAB) have a lower resistance over the entire frequency spectrum. From Fig. 3(a), we can clearly see that the resistances of polymers of without CTAB are larger in both low and high frequencies. Fig. 3(b) displays the DPV response obtained at the three electrodes in a 0.1 M PBS (pH = 4) containing 200 lM of paracetamol. As depicted in Fig. 3(b), the polymer HNFs (from 0.009 M CTAB) has high sensitivity for detection of paracetamol, which due to polymer HNFs (from 0.009 M CTAB) possess high active surface and fast electron transfer rate. From Fig S1, the p–p stacking and the strong non-covalent force between paracetamol molecules and pendant thiol groups in polymers can significantly improve the sensing performance of sensor. The results of intra-assay and inter-assay coefficient of variation for polymers NHFs are shown in Table S2. The value of relative standard deviation (RSD) for seven detections is below 5%, indicating good precision. Generally, polymer nanofiber can be fabricated by template method, electrospinning method and seed polymerization method [8–10]. In our case, we developed a template method in CHCl3 for preparing the polymer HNFs, which can be assigned for the self-assembling of CTAB and monomer in reaction system. And, this method can be a simple way for forming polymer HNFs, which is hardly generated by other methods.
4. Conclusion In summary, the self-assembly behavior of CTAB surfactants in CHCl3 system is contribute to the formation of conductive polymer hollow nanofibers. It also provides significant control over the
nucleation and arrangement of PProDOT-(MeSH)2 molecular chains in the polymerization process. The non-covalent force and p- p stacking between the PProDOT-(MeSH)2 HNFs and paracetamol molecules are beneficial to improve the sensitivity and electrocatalytic performance. In addition, the short total assay time (108 h) of the method developed is also a great advantage of this study. Author contributions Ruanye Zhang carried out the sample preparation and the experimental measurements and participated in the study of material structures and data analysis. Mihray Abdulla, Ruxangul Jamal, Yi Ge, Wenli Zhang, Zongna Yu, Yinqiang Yan, , and Yingcheng Liu conceived the study, carried out the data analysis, and drafted the manuscript. Tursun Abdiryim coordinated the research and revised the manuscript. All authors read and approved the final version of the manuscript. Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Acknowledgment We gratefully acknowledge financial support from the National Natural Science Foundation of China (No. 21564014, No. 21764014). Appendix A. Supplementary data Supplementary data to this article can be found online at https://doi.org/10.1016/j.matlet.2019.127206. References: [1] M.E. Robinson, A. Nazemi, D.J. Lunn, D.W. Hayward, C.E. Boott, M.S. Hsiao, R.L. Harniman, S.A. Davis, G.R. Whittell, R.M. Richardson, L. De Cola, I. Manners, Dimensional control and morphological transformations of supramolecular polymeric nanofibers based on cofacially-stacked planar amphiphilic platinum (II) complexes, ACS Nano 11 (9) (2017) 9162–9175. [2] H. Jiaxing, V. Shabnam, B.H. Weiller, R.B. Kaner, Polyaniline nanofibers: facile synthesis and chemical sensors, J. Am. Chem. Soc. 125 (2) (2003) 314. [3] S.C. Luo, J. Sekine, B. Zhu, H. Zhao, A. Nakao, H.H. Yu, Polydioxythiophene nanodots, nonowires, nano-networks, and tubular structures: the effect of
R. Zhang et al. / Materials Letters 263 (2020) 127206
[4]
[5]
[6] [7]
functional groups and temperature in template-free electropolymerization, Acs Nano 6 (4) (2012) 3018–3026. L. Ouyang, B. Wei, C. Kuo, S. Pathak, B. Farrell, D.C. Martin, Enhanced PEDOT adhesion on solid substrates with electrografted P(EDOT-NH2), Sci. Adv. 3 (3) (2017) e1600448. T. Goda, M. Toya, A. Matsumoto, Y. Miyahara, Poly(3,4-ethylenedioxythiophene) bearing phosphorylcholine groups for metal-free, antibody-free, and lowimpedance biosensors specific for C-reactive protein, Acs Appl. Mater. Interfaces 7 (49) (2015) 27440–27448. M.G. Han, S.H. Foulger, Facile synthesis of poly(3,4-ethylenedioxythiophene) nanofibers from an aqueous surfactant solution, Small 2 (10) (2006) 1164–1169. T. Yamamoto, K. Shiraishi, M.Y. Abla, I. Yamaguchi, L.B. Groenendaal, Neutral poly 3,4-ethylenedioxythiophene-2,5-diyl)s: preparation byorganometallic
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polycondensation and their unique p-doping behavior, Polymer 43 (2002) 711–719. [8] W. Guan, S. Li, L. Tang, Fabrication polymer nanofiber networks with regulated microstructures via RAFT polymerization of supramolecular gels in different solvents, Eur. Polymer J. 120 (2019) 109210. [9] B. Guo, Y. Zhao, W. Wu, H. Meng, H. Zou, J. Chen, G. Chu, Research on the preparation technology of polyaniline nanofiber based on high gravity chemical oxidative polymerization, Chem. Eng. Process.: Process Intensification 70 (2013) 1–8. [10] T. Li, Z. Qin, Y. Shen, X. Xu, N. Liu, Y. Zhang, Polyaniline nanofibers formed by seed polymerization through heat treatment for synergistic enhancement of Cr (VI) removal, Mater. Lett. 252 (2019) 130–133.
Contents lists available at ScienceDirect
Materials Letters journal homepage: www.elsevier.com/locate/mlblue
The pendent thiol group grafed poly(3,4-proplenedioxythiophene) hollow nanofiber for electrochemical sensing Ruanye Zhang, Mihray Abdulla, Ruxangul Jamal, Yi Ge, Wenli Zhang, Zongna Yu, Yinqiang Yan, Yingcheng Liu, Tursun Abdiryim Key Laboratory of Petroleum and Gas Fine Chemicals, Educational Ministry of China, School of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, People’s Republic of China
a r t i c l e
i n f o
Article history: Received 21 October 2019 Received in revised form 24 November 2019 Accepted 20 December 2019 Available online 20 December 2019 Keywords: Microstructure Hollow nanofibers Thiol group PEDOT Sensors
a b s t r a c t The pendent thiol group grafed poly(3,4-proplenedioxythiophene) (PProDOT-(MeSH)2) hollow nanofibers (HNFs) were prepared via surfactant-assisted method of cetyltrimethyl ammonium bromide (CTAB), and the influence of CTAB concentration on the morphology and electrochemical performance of PProDOT(MeSH)2 were investigated. The physical and chemical properties of PProDOT-(MeSH)2 HNFs were studied by FT-IR, UV–vis, XRD, SEM, TEM and the electrocatalytic activity were evaluated by detecting paracetamol using differential pulse voltammetry (DPV) techniques. The results showed that the PProDOT-(MeSH)2 HNFs in 0.009 M CTAB exhibited a much better electrocatalytic performance. Ó 2019 Published by Elsevier B.V.
1. Introduction One-dimensional conducting polymers nanofibers possess high specific surface area, abundant active sites and high conductivity etc. that endow them with improved performances for application such as chemical sensors [1,2]. PEDOT-based conductive nanomaterials are widely used in biosensors due to their excellent performance. However, the molecular recognition effect of conductive polymers such as PEDOT is not obvious, which weakens their applications in biosensor. Accordingly, introducing proper functional groups (such as –COOH, –NH2, –OH, –SH, etc.) into the PEDOT skeleton can be used as novel electrochemical sensing materials due to the special adsorption and bonding interactions among these functional groups and small biological or drug molecules [3,4]. Here we report a facile chemical route to prepare HNFs of PProDOT-(MeSH)2 under ambient conditions using chemical oxidation polymerization. The pendent thiol groups grafed PProDOT HNFs can significantly improve the electrochemical sensing ability by virtue of their unique electronic transmission channels, excellent molecular recognition ability and unique electrocatalytic properties. Electrolyte is easier to enter the hollow cavity of HNFs, and the pendent thiol group in the polymer also can produce
E-mail addresses: [email protected] (R. Jamal), [email protected] (T. Abdiryim) https://doi.org/10.1016/j.matlet.2019.127206 0167-577X/Ó 2019 Published by Elsevier B.V.
strong non-covalent force with the analytes, which can significantly improve the sensitivity of the sensor. Paracetamol was detected by DPV systematically to research the relationship between the structure and the properties of the polymers. The results showed that the uniform PProDOT-(MeSH)2 HNFs in 0.009 M CTAB exhibits the best electrochemical properties, which indicated that the pendent functional groups grafted polymers HNFs may hold great promise for the design of electrochemical sensors for practical application.
2. Experimental 131 mg (0.009 M) CTAB dissolved in 20 mL CHCl3 and ultrasound for 10 min, then 10 mL of CHCl3 containing 20 mg ProDOT-(MeSH)2 monomer were added to the solution ultrasound for 15 min, and stirred for 30 min under 0 °C. Finally, 10 mL of CHCl3 containing 100 mg of FeCl3 were dropped into the above suspension, stirred at room temperature for 24 h. The products were centrifuged and washed with chloroform, methanol, water, and then dried. The obtained polymer were denoted as PProDOT(MeSH)2 (CTAB, 0.009 M). The detailed description of synthesis of the monomer and concentration of CTAB (Table S1) for polymers are provided in the SI. And, the preparation modified electrodes are also presented in the SI.
R. Zhang et al. / Materials Letters 263 (2020) 127206
3. Results and discussion The microstructure of the as-prepared PProDOT-(MeSH)2 samples in CHCl3 system with different concentration of CTAB were investigated by SEM and TEM (Fig. 1A). As shown in Fig. 1a and f, the polymer without added CTAB shows patch network structure. From Fig. 1b, g, it can be clearly seen that the polymer have irregular structure with a small part of the nanorods in 0.005 M CTAB. While the polymer present a uniform fibrous shape with the diameter of ~50–80 nm. Form the TEM images of Fig. 1h, the hollow structure of the polymer fiber can be clearly judged from the shadow thickness of the polymer. The appearance of hollow fibrous morphology is due to the formation of fibers or rod micelles by self-assembly of surfactant CTAB. Firstly, at a certain concentration, CTAB self-assembles into fibrous micelles. When monomers are added, due to the weak acidity of the thiol groups of ProDOT-(MeSH)2, they can attract each other with the polar end groups of CTAB, so the monomers are uniformly coated on the micelles of CTAB and the polymer film is formed when
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the oxidant of FeCl3 was added. Finally, polymer HNFs were obtained when the CTAB soft template was removed. A simple diagram of polymer HNFs is shown in the Fig. 1(B). After the amount of CTAB reaches a certain level (0.014 M), the morphology of the initial fiber began to change obviously (Fig. 1d and i). Combined with Fig. 1c and d, it is clear seen that blocks structure and inhomogeneity fiber begin to appear in polymer fibers. It also can be seen from the Fig. 1h and i that the diameter of polymer nanofibers increases obviously and the accumulation is more serious. When the concentration of CTAB is up to 0.018 M, the structure of tubular, granular, and few flaky are co-existed in (Fig. 1j). This may be caused by the excessive amount of CTAB, which destroys the action of the surfactant to form tubular micelles. Fig. 2(a) gives the FT-IR spectra of PProDOT-(MeSH)2. All polymers have similar vibration bands appeared at around 3300–3640, ~2921, ~1659, ~1475, ~1359, ~1048 and ~847 cm 1 which are from thiophene ring, while the broad peaks at 3300–3640 cm 1 for all samples can be assigned to S-H vibration
Fig. 1. (A) SEM and TEM images of PProDOT-(MeSH)2 in different concentrations of CTAB, (a) 0.0 M CTAB; (b) 0.005 M CTAB; (c) 0.009 M CTAB; (b) 0.014 M CTAB; (e) 0.018 M CTAB; (B) Schematic diagram of hollow nanofiber formation.
Fig. 2. (a) FT-IR; (b) UV–Vis; (c) XRD patterns of PProDOT(MeSH)2 in different concentrations of CTAB.
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R. Zhang et al. / Materials Letters 263 (2020) 127206
Fig. 3. (a) EIS different modified GCEs in 0.1 M H2SO4 aqueous solution; (b) DPV response curves of different modified GCEs;
[5]. Fig. 2(b) shows the UV–vis spectra of PProDOT-(MeSH)2. The polymers from 0.005 M, 0.009 M and 0.014 M CTAB display broad absorption peaks at ~425–620 nm with several shoulders, and they are ascribed to the p-p* transition of the thiophene ring [6]. However, the polymers from 0 M and 0.018 M CTAB have no obvious peaks at ~425–620 nm implying the low conjugation degree of polymer. The XRD patterns (Fig. 2(c)) show that all polymers have similar broad diffraction peaks (2h = 15°~20°) and sharp diffraction peaks (2h = 33.4°, 35.8°, 49.5°, 54°), which are from the interchain planar stacking of polymer chains and the FeC14 1 doping agent, respectively [7]. It is obvious that diffraction peak of polymer HNFs (from 0.009 M CTAB) is higher than others, indicating that polymer HNFs have relatively high crystallization degree. The electrochemical behavior of the samples modified electrodes were investigated by EIS and DPV. As shown in Fig. 3(a), the polymer HNFs (from 0.009 M CTAB) have a lower resistance over the entire frequency spectrum. From Fig. 3(a), we can clearly see that the resistances of polymers of without CTAB are larger in both low and high frequencies. Fig. 3(b) displays the DPV response obtained at the three electrodes in a 0.1 M PBS (pH = 4) containing 200 lM of paracetamol. As depicted in Fig. 3(b), the polymer HNFs (from 0.009 M CTAB) has high sensitivity for detection of paracetamol, which due to polymer HNFs (from 0.009 M CTAB) possess high active surface and fast electron transfer rate. From Fig S1, the p–p stacking and the strong non-covalent force between paracetamol molecules and pendant thiol groups in polymers can significantly improve the sensing performance of sensor. The results of intra-assay and inter-assay coefficient of variation for polymers NHFs are shown in Table S2. The value of relative standard deviation (RSD) for seven detections is below 5%, indicating good precision. Generally, polymer nanofiber can be fabricated by template method, electrospinning method and seed polymerization method [8–10]. In our case, we developed a template method in CHCl3 for preparing the polymer HNFs, which can be assigned for the self-assembling of CTAB and monomer in reaction system. And, this method can be a simple way for forming polymer HNFs, which is hardly generated by other methods.
4. Conclusion In summary, the self-assembly behavior of CTAB surfactants in CHCl3 system is contribute to the formation of conductive polymer hollow nanofibers. It also provides significant control over the
nucleation and arrangement of PProDOT-(MeSH)2 molecular chains in the polymerization process. The non-covalent force and p- p stacking between the PProDOT-(MeSH)2 HNFs and paracetamol molecules are beneficial to improve the sensitivity and electrocatalytic performance. In addition, the short total assay time (108 h) of the method developed is also a great advantage of this study. Author contributions Ruanye Zhang carried out the sample preparation and the experimental measurements and participated in the study of material structures and data analysis. Mihray Abdulla, Ruxangul Jamal, Yi Ge, Wenli Zhang, Zongna Yu, Yinqiang Yan, , and Yingcheng Liu conceived the study, carried out the data analysis, and drafted the manuscript. Tursun Abdiryim coordinated the research and revised the manuscript. All authors read and approved the final version of the manuscript. Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Acknowledgment We gratefully acknowledge financial support from the National Natural Science Foundation of China (No. 21564014, No. 21764014). Appendix A. Supplementary data Supplementary data to this article can be found online at https://doi.org/10.1016/j.matlet.2019.127206. References: [1] M.E. Robinson, A. Nazemi, D.J. Lunn, D.W. Hayward, C.E. Boott, M.S. Hsiao, R.L. Harniman, S.A. Davis, G.R. Whittell, R.M. Richardson, L. De Cola, I. Manners, Dimensional control and morphological transformations of supramolecular polymeric nanofibers based on cofacially-stacked planar amphiphilic platinum (II) complexes, ACS Nano 11 (9) (2017) 9162–9175. [2] H. Jiaxing, V. Shabnam, B.H. Weiller, R.B. Kaner, Polyaniline nanofibers: facile synthesis and chemical sensors, J. Am. Chem. Soc. 125 (2) (2003) 314. [3] S.C. Luo, J. Sekine, B. Zhu, H. Zhao, A. Nakao, H.H. Yu, Polydioxythiophene nanodots, nonowires, nano-networks, and tubular structures: the effect of
R. Zhang et al. / Materials Letters 263 (2020) 127206
[4]
[5]
[6] [7]
functional groups and temperature in template-free electropolymerization, Acs Nano 6 (4) (2012) 3018–3026. L. Ouyang, B. Wei, C. Kuo, S. Pathak, B. Farrell, D.C. Martin, Enhanced PEDOT adhesion on solid substrates with electrografted P(EDOT-NH2), Sci. Adv. 3 (3) (2017) e1600448. T. Goda, M. Toya, A. Matsumoto, Y. Miyahara, Poly(3,4-ethylenedioxythiophene) bearing phosphorylcholine groups for metal-free, antibody-free, and lowimpedance biosensors specific for C-reactive protein, Acs Appl. Mater. Interfaces 7 (49) (2015) 27440–27448. M.G. Han, S.H. Foulger, Facile synthesis of poly(3,4-ethylenedioxythiophene) nanofibers from an aqueous surfactant solution, Small 2 (10) (2006) 1164–1169. T. Yamamoto, K. Shiraishi, M.Y. Abla, I. Yamaguchi, L.B. Groenendaal, Neutral poly 3,4-ethylenedioxythiophene-2,5-diyl)s: preparation byorganometallic
127209
polycondensation and their unique p-doping behavior, Polymer 43 (2002) 711–719. [8] W. Guan, S. Li, L. Tang, Fabrication polymer nanofiber networks with regulated microstructures via RAFT polymerization of supramolecular gels in different solvents, Eur. Polymer J. 120 (2019) 109210. [9] B. Guo, Y. Zhao, W. Wu, H. Meng, H. Zou, J. Chen, G. Chu, Research on the preparation technology of polyaniline nanofiber based on high gravity chemical oxidative polymerization, Chem. Eng. Process.: Process Intensification 70 (2013) 1–8. [10] T. Li, Z. Qin, Y. Shen, X. Xu, N. Liu, Y. Zhang, Polyaniline nanofibers formed by seed polymerization through heat treatment for synergistic enhancement of Cr (VI) removal, Mater. Lett. 252 (2019) 130–133.