Raspberry-like Pt clusters with controlled spacing produced by deposition of loaded block copolymer micelles from supercritical CO2

Abstract

We present a “one-pot” supercritical approach for creating organized metal nanoparticle arrays. For this an improved method of deposition of micelles formed by semifluorinated poly(methyl methacrylate)-block-poly(perfluoroalkyl methacrylate) diblock copolymers in supercritical CO2 solution is applied. The presented approach provides metal clusters with a controlled inter-particle spacing and relatively narrow size distributions in a single-step “one-pot” process during which the micelle formation proceeds simultaneously with organometallic Pt-precursor dissolution and reduction inside the high-pressure vessel containing a proper substrate. Subsequent decompression of the vessel results in patterned clusters of reduced metallic nanoparticles on the substrate. Presented approach of producing such raspberry-like Pt clusters is relatively simple as compared to other time-consuming multi-step processes, and the resulting structures seem to be promising for electro-catalytical applications.