Mesoporous Platinum with Giant Mesocages Templated from Lyotropic Liquid Crystals Consisting of Diblock Copolymers

Abstract

Templated synthesis of nanostructured metals with tunable composition, structure, and morphology allows us to finely control the metals properties, which is a typical example of materials nanoarchitectonics that emphasizes the importance of novel size-and shape-dependent properties. [1] Traditionally, various nanostructured metals (for example, nanowire arrays, [2] bicontinuous nanowire networks, [3] nanoparticle arrays [4] ) have been prepared by utilizing hard templates including mesoporous silica. Currently, lyotropic liquid crystals (LLCs), formed by assembling C n (EO) m -type surfactants (EO = ethylene oxide), have been utilized as soft templates to directly prepare mesoporous metals with hexagonally packed cylindrical mesospace. [5, 6] In such LLCs, metal nanoparticles with almost uniform size are continuously deposited to form unique frameworks consisting of connected nanoparticles, [7] which contribute to the development of novel metal-based nanomaterials that are not achievable by hard templating. [8] Surprisingly, all the mesoporous metals prepared by the soft templating technique have been limited to 2D hexagonal mesostructures with mesopores less than 4 nm in diameter. Both the limits of mesostructures and pore size seriously

Hierarchical Nanoporous Gold-Platinum with Heterogeneous Interfaces for Methanol Electrooxidation

“…As shown in Fig. 3(a), the well-defined hydrogen desorption/adsorption peaks from Pt are observed in the potential region from −0.2 to 0 V for HiNAP-3 and commercial Pt plate, and these characters are consistent with the previous investigations614. Moreover, the quasi-reversible oxidation/reduction peaks are observed in the potential range from 0.3 to 1.0 V, which are associated with the Au/Pt oxidation and reduction in aqueous solution3738.…”

“…Noble metal nanostructures with the interconnected channels have aroused significant scientific interest in the fields of environmental protection 1 , renewable energy 2 3 , and disease diagnosis 4 . Specifically, nanoporous platinum (Pt) or Pt nanoclusters usually have a number of interstitials and large active surface area, all of which result in both the extraordinary catalytic activity towards the electrochemical oxidation of methanol 5 6 7 8 , ethanol 9 , formic acid 10 , and electrochemical detection including glucose and hydrogen peroxide 3 11 . All these performances originate from the superior catalysis of the Pt nanostructures with nanoscale pores, which can be usually synthesized by various methods, such as dealloying 7 10 , template methods 6 12 , coating process 13 14 , and seed growth 9 .…”

“…Specifically, nanoporous platinum (Pt) or Pt nanoclusters usually have a number of interstitials and large active surface area, all of which result in both the extraordinary catalytic activity towards the electrochemical oxidation of methanol 5 6 7 8 , ethanol 9 , formic acid 10 , and electrochemical detection including glucose and hydrogen peroxide 3 11 . All these performances originate from the superior catalysis of the Pt nanostructures with nanoscale pores, which can be usually synthesized by various methods, such as dealloying 7 10 , template methods 6 12 , coating process 13 14 , and seed growth 9 . Essentially, the strategies to design prospective electrodes include several aspects, such as the rigid skeletons to avoid the unexpected agglomeration, enough hollow channels in favor of electrolyte transportation, high catalytic activity to lower the usage of noble metals, and the tolerance ability toward the poisoning species.…”

Self-assembled ordered mesoporous metals

“…First introduced by Attard and further explored by Kuroda, metal salts have been reduced in the presence of small molecule surfactants [59][60][61] and, more recently, block copolymers [62]. This provides a rapid route to the formation of mesoporous metals, but this approach is limited to metals that can be electrodeposited from aqueous solution.…”

Electrochemically dealloyed platinum with hierarchical pore structure as highly active catalytic coating

“…Respective preparation methods include electrodeposition, galvanic replacement, reduction of a metal salt in the presence of structure-directing surfactant [25][26][27][28] as well as electro-chemical dealloying of metal alloys (see e.g. Respective preparation methods include electrodeposition, galvanic replacement, reduction of a metal salt in the presence of structure-directing surfactant [25][26][27][28] as well as electro-chemical dealloying of metal alloys (see e.g.…”