In this paper, we report a simple and facile self-assembly method to successfully fabricate cationic metal porphyrin-MtTMPyP(Mt= Cobalt(Ⅱ), Manganese(Ⅲ), or Iron(Ⅲ); TMPyP = 5, 10, 15, 20-tetrakis(N-methylpyridiniu...In this paper, we report a simple and facile self-assembly method to successfully fabricate cationic metal porphyrin-MtTMPyP(Mt= Cobalt(Ⅱ), Manganese(Ⅲ), or Iron(Ⅲ); TMPyP = 5, 10, 15, 20-tetrakis(N-methylpyridinium-4-yl) porphyrin) intercalated into the layer of graphene oxide(GO) by the cooperative effects of electrostatic and π-π stacking interaction between positively charged metal porphyrin and negatively charged GO sheets. Followed by reduction with hydrazine vapor, a series of novel 2 D MtTMPyP/rGO_n were fabricated. The as-prepared 2 D hybrids were fully characterized and tested as non-noble metal catalysts for oxygen reduction reaction(ORR) in an alkaline medium. The MtTMPyP/rGO_n hybrids, especially CoTMPyP/rGO_5, demonstrated an improved electrocatalytic activity for ORR and a number of exchanged electrons close to 4-electron reaction, increased stability and excellent tolerance to methanol, showing a potential alternative catalyst for ORR in fuel cells and air batteries.展开更多
Through material innovation,nanoscale structural design and hybrid manufacturing methods,great efforts have been made in developing high-performance energy storage systems.These devices can be comprised of twodimensio...Through material innovation,nanoscale structural design and hybrid manufacturing methods,great efforts have been made in developing high-performance energy storage systems.These devices can be comprised of twodimensional(2D)nanomaterials,such as MXene,and show promise for use in energy storage devices.In order to achieve better electrochemical properties of MXene,one crucial technique is to modify its structure by introducing defects or heteroatom dopants,which may expand the interlayer spacing and increase the ion transfer kinetics during the charge/discharge process.Here,a modified two-step multi-element strategy is explored utilizing ammonium citrate as intercalant and nitrogen source to enhance the level of heteroatom doping during annealing of MXene with sulfur.The resulting nitrogen/sulfur co-doped MXene displayed enhanced gravimetric capacitance(495 F g^(-1) at 1 A g^(-1)),outstanding rate capability(180 F g^(-1) at 10 A g^(-1))and excellent cycle stability(98%retention after 6000 charge/discharge cycles).The synthesis of NS-MXene reveals a novel and facile multiheteroatom pathway for functionalizing Ti_(3)C_(2)Tx MXene and demonstrates the potential variety of this family of modified MXenes that has yet to be explored,as well as unveils great promise for use in applications such as high performance supercapacitors.展开更多
基金supported by Natural Science Fund of Jiangsu Province (BK20141247, BK20140447)Exceptional Talent Project in Jiangsu Province (2015-XCL-035)+3 种基金University Science Research Project of Jiangsu Province (13KJB430005, 11KJA430008)funded by the Priority Academic Program development of Jiangsu Higher Education InstitutionsJiangsu Province universities' "blue and green blue project"financial support from the ARC (CE140100012, FT130100380, and DP170102267)
文摘In this paper, we report a simple and facile self-assembly method to successfully fabricate cationic metal porphyrin-MtTMPyP(Mt= Cobalt(Ⅱ), Manganese(Ⅲ), or Iron(Ⅲ); TMPyP = 5, 10, 15, 20-tetrakis(N-methylpyridinium-4-yl) porphyrin) intercalated into the layer of graphene oxide(GO) by the cooperative effects of electrostatic and π-π stacking interaction between positively charged metal porphyrin and negatively charged GO sheets. Followed by reduction with hydrazine vapor, a series of novel 2 D MtTMPyP/rGO_n were fabricated. The as-prepared 2 D hybrids were fully characterized and tested as non-noble metal catalysts for oxygen reduction reaction(ORR) in an alkaline medium. The MtTMPyP/rGO_n hybrids, especially CoTMPyP/rGO_5, demonstrated an improved electrocatalytic activity for ORR and a number of exchanged electrons close to 4-electron reaction, increased stability and excellent tolerance to methanol, showing a potential alternative catalyst for ORR in fuel cells and air batteries.
基金the Tsinghua-Foshan Innovation Special Fund(Grant No.2019THFS0125)support from Alfred Deakin Postdoctoral Fellowship.Z.Wang acknowledges financial support from China Scholarship Council(File No.201606930013)+2 种基金the Australian Research Council for funding(FT130100380,IH140100018 and DP190103290)the ARC Centre of Excellence for Electromaterials Science(ACES)(No.CE140100012)the Victorian Node of the Australian National Fabrication Facility(ANFF).
文摘Through material innovation,nanoscale structural design and hybrid manufacturing methods,great efforts have been made in developing high-performance energy storage systems.These devices can be comprised of twodimensional(2D)nanomaterials,such as MXene,and show promise for use in energy storage devices.In order to achieve better electrochemical properties of MXene,one crucial technique is to modify its structure by introducing defects or heteroatom dopants,which may expand the interlayer spacing and increase the ion transfer kinetics during the charge/discharge process.Here,a modified two-step multi-element strategy is explored utilizing ammonium citrate as intercalant and nitrogen source to enhance the level of heteroatom doping during annealing of MXene with sulfur.The resulting nitrogen/sulfur co-doped MXene displayed enhanced gravimetric capacitance(495 F g^(-1) at 1 A g^(-1)),outstanding rate capability(180 F g^(-1) at 10 A g^(-1))and excellent cycle stability(98%retention after 6000 charge/discharge cycles).The synthesis of NS-MXene reveals a novel and facile multiheteroatom pathway for functionalizing Ti_(3)C_(2)Tx MXene and demonstrates the potential variety of this family of modified MXenes that has yet to be explored,as well as unveils great promise for use in applications such as high performance supercapacitors.
