In this work, three different aqueous solutions containing imidazole-based ILs w让h different alkyl chain lengths ([Cnmim]Br, n = 2Z 6,12) were adopted as the medium for the synthesis of ionic liquid-polypyrrole (IL-P...In this work, three different aqueous solutions containing imidazole-based ILs w让h different alkyl chain lengths ([Cnmim]Br, n = 2Z 6,12) were adopted as the medium for the synthesis of ionic liquid-polypyrrole (IL-PPy) composites. Herein, the ILs undertook the roles of the pyrrole solvent, the media for emulsion polymerization of PPy and PPy dopants, respectively. The electrochemical performances of the three IL-PPy composites on a glassy carbon electrode (GCE) were investigated by electrochemical experiments, which indicated that [Ci2mim]Br-PPy (Ci2~PPy) composites displayed better electrochemical performance due to their larger surface area and firmer immobilization on the GCE. Further, Ci2?PPy/GCE were decorated with Au microparticles by electrodeposition that can not only increase the conductivity, but also immobilize sufficient biomolecules on the electrode. Then, the obtained Ci2~PPy^Au/GCE with outstanding electrochemical performance was employed as a horseradish peroxidase (HRP) immobilization platform to fabricate a novel Ci2-PPy-Au-HRP/GCE biosensor for H2O2 detection. The results showed that the prepared Ci2-PPy-Au-HRP/GCE biosensor exhibited high sensitivity, fast response, and a wide detection range as well as low detection limit towards H2O2. This work not only provides an outstanding biomolecule immobilization matrix for the fabrication of highly sensitive biosensors, but also advances the understanding of the roles of ILs in improving the electrochemical performance of biosensors.展开更多
Coatings serve as ideal protective films for mechanical systems,providing dependable as well as efficient lubrication because of their unique structure along with outstanding tribological characteristics.Inspired by ...Coatings serve as ideal protective films for mechanical systems,providing dependable as well as efficient lubrication because of their unique structure along with outstanding tribological characteristics.Inspired by the“bricks-and-mortar”structure,we prepared layered graphene oxide(GO)composite finishes strengthened with polyvinyl alcohol(PVA)and borax.Our study demonstrates that the tribological properties of the GO-based coating on 304 stainless steel(SS304)are potentially greatly affected through PVA,GO,and annealing.By optimizing the composition,we achieved the PVA_(40 wt%)/GO_(0.01 wt%)/borax composite coating,which exhibited the lowest average coefficient of friction(COF)of 0.021±0.003(a 97.86%reduction compared to control SS304)with minimal wear and abrasion even in a water environment.We found that the enhanced mechanical characteristics as well as elastic recovery within the coating were attributed to the hydrogen bonds and cross-linking between PVA and borax,which led to stress distribution.Reduced friction was further aided by the formation of a hydrated layer at the friction interface.As a result,the coating demonstrated remarkable durability,maintaining a low COF during long sliding distances(576 m,28,800 cycles,significantly longer than previously reported)without breaking.展开更多
基金the National Natural Science Foundation of China(Project No.21476072)the Fundamental Research Funds for the Central Universities.
文摘In this work, three different aqueous solutions containing imidazole-based ILs w让h different alkyl chain lengths ([Cnmim]Br, n = 2Z 6,12) were adopted as the medium for the synthesis of ionic liquid-polypyrrole (IL-PPy) composites. Herein, the ILs undertook the roles of the pyrrole solvent, the media for emulsion polymerization of PPy and PPy dopants, respectively. The electrochemical performances of the three IL-PPy composites on a glassy carbon electrode (GCE) were investigated by electrochemical experiments, which indicated that [Ci2mim]Br-PPy (Ci2~PPy) composites displayed better electrochemical performance due to their larger surface area and firmer immobilization on the GCE. Further, Ci2?PPy/GCE were decorated with Au microparticles by electrodeposition that can not only increase the conductivity, but also immobilize sufficient biomolecules on the electrode. Then, the obtained Ci2~PPy^Au/GCE with outstanding electrochemical performance was employed as a horseradish peroxidase (HRP) immobilization platform to fabricate a novel Ci2-PPy-Au-HRP/GCE biosensor for H2O2 detection. The results showed that the prepared Ci2-PPy-Au-HRP/GCE biosensor exhibited high sensitivity, fast response, and a wide detection range as well as low detection limit towards H2O2. This work not only provides an outstanding biomolecule immobilization matrix for the fabrication of highly sensitive biosensors, but also advances the understanding of the roles of ILs in improving the electrochemical performance of biosensors.
基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB 0470202)the International Partnership Program of Chinese Academy of Sciences Project for Grand Challenges(No.307GJHZ2022034GC)+1 种基金the Science and Technology Development Fund of Pudong New District(No.PKJ2020-N007)the Fundamental Research Funds for the Central Universities(No.222201717003)for their financial support.
文摘Coatings serve as ideal protective films for mechanical systems,providing dependable as well as efficient lubrication because of their unique structure along with outstanding tribological characteristics.Inspired by the“bricks-and-mortar”structure,we prepared layered graphene oxide(GO)composite finishes strengthened with polyvinyl alcohol(PVA)and borax.Our study demonstrates that the tribological properties of the GO-based coating on 304 stainless steel(SS304)are potentially greatly affected through PVA,GO,and annealing.By optimizing the composition,we achieved the PVA_(40 wt%)/GO_(0.01 wt%)/borax composite coating,which exhibited the lowest average coefficient of friction(COF)of 0.021±0.003(a 97.86%reduction compared to control SS304)with minimal wear and abrasion even in a water environment.We found that the enhanced mechanical characteristics as well as elastic recovery within the coating were attributed to the hydrogen bonds and cross-linking between PVA and borax,which led to stress distribution.Reduced friction was further aided by the formation of a hydrated layer at the friction interface.As a result,the coating demonstrated remarkable durability,maintaining a low COF during long sliding distances(576 m,28,800 cycles,significantly longer than previously reported)without breaking.
