Platinum nanocatalysts loaded on graphene oxide-dispersed carbon nanotubes with greatly enhanced peroxidase-like catalysis and electrocatalysis activities

Abstract

A powerful enzymatic mimetic has been fabricated by employing graphene oxide (GO) nanocolloids to disperse conductive carbon supports of hydrophobic carbon nanotubes (CNTs) before and after the loading of Pt nanocatalysts. The resulting GOCNT-Pt nanocomposites could present improved aqueous dispersion stability and Pt spatial distribution. Unexpectedly, they could show greatly enhanced peroxidase-like catalysis and electrocatalysis activities in water, as evidenced in the colorimetric and electrochemical investigations in comparison to some inorganic nanocatalysts commonly used. Moreover, it is found that the new enzyme mimetics could exhibit peroxidase-like catalysis activity comparable to natural enzymes; yet, they might circumvent some of their inherent problems in terms of catalysis efficiency, electron transfer, environmental stability, and cost effectiveness. Also, sandwiched electrochemical immunoassays have been successfully conducted using GOCNT-Pt as enzymatic tags. Such a fabrication avenue of noble metal nanocatalysts loaded on well-dispersed conductive carbon supports should be tailored for the design of different enzyme mimics promising the extensive catalysis applications in environmental, medical, industrial, and particularly aqueous biosensing fields.

Interfacial peroxidase-like catalytic activity of surface-immobilized cobalt phthalocyanine on multiwall carbon nanotubes

“…[15][16][17] In our previous studies, we conrmed that the presence of multiwall carbon nanotubes (MWCNTs) could greatly enhance the catalytic activity of cobalt phthalocyanine (CoPc, an enzyme mimic catalyst) for H 2 O 2 activation because of their excellent electrical properties. [15][16][17] In our previous studies, we conrmed that the presence of multiwall carbon nanotubes (MWCNTs) could greatly enhance the catalytic activity of cobalt phthalocyanine (CoPc, an enzyme mimic catalyst) for H 2 O 2 activation because of their excellent electrical properties.…”

Honeycomb-like nitrogen-doped porous carbon supporting Pt nanoparticles as enzyme mimic for colorimetric detection of cholesterol

“…Therefore, in our experiment, PCN shows an enhanced activity than PC. Pt nanoparticles have been reported as one of typical peroxidase mimetics [11], so an obvious absorption at 652 nm of the TMB + H 2 O 2 + Pt system (curve d) is observed. When Pt and PCN were mixed mechanically as the ratio of samples, there is also an adsorption at 652 nm.…”

“…A series of inorganic nanomaterials including Au NPs [3], Fe 3 O 4 NPs [4], Co 3 O 4 NPs [5], V 2 O 5 nanowires [6], carbon dots [7], graphene oxide [8], single-walled carbon nanotubes [9] and metallic nanocomposites [10] have been found to present unexpected enzyme-like activities. As the most known one, noble metal platinum (Pt) is chemically inert at bulk scales but can serve as the important catalysts at nanoscales because of their unique size, shape and the increased specific surface area [11]. Many reports demonstrated that Pt nanoparticles can exhibit peroxidase-like catalysis activity for the detection of H 2 O 2 [12,13].…”

Heterogeneous Catalysis on Nanostructured Carbon Material Supported Catalysts

“…519 Interestingly, a powerful enzymatic mimetic has been fabricated by employing GO nanocolloids to disperse conductive carbon supports of hydrophobic CNTs before and after the loading of Pt nanoparticles. 520 The resulting GO@CNT-Pt nanocomposites present improved aqueous dispersion stability and Pt spatial distribution. They showed greatly enhanced peroxidase-like catalysis and electrocatalytic activities in water.…”