Single gyroid-structured metallic nanoporous spheres fabricated from double gyroid-forming block copolymers via templated electroless plating

Herein, we suggest a methodology for the fabrication of well-defined metallic nanoporous spheres with single gyroid (SG) structure by simply using self-assembled diblock copolymer with double gyroid (DG) structure as a template for electroless plating. Note that owing to the consideration of thermodynamic stability, the self-assembly of diblock copolymers gives rise to a DG phase instead of an SG phase. By controlling the nucleus density for the reduction of Pd ions within the diblock copolymer template, SG-structured Ni can be easily fabricated through the nucleation and growth processes. Consequently, nanoporous Ni spheres with uniform pore sizes and high specific surface areas can be fabricated. Moreover, nanoporous Ni spheres with controlled microscale particle sizes can thus be obtained by controlling the reduction time for the growth of Ni, which enables the feasibility of recyclability via magnetic fields. The combination of structural and morphological characteristics of the fabricated nanoporous Ni spheres make them appealing for use in a wide variety of applications, such as high-efficiency and well selectivity hydrogenation catalysts with recyclability due to their narrow pore size distributions, high specific surface areas, 3D curved surfaces, and controlled microscale particle sizes. Catalysts: perfecting the recipe for metallic microspheres with uniform nanoporous An improved synthesis for porous nickel catalysts that can be captured and recycled has been developed. Metals on curved surfaces have atoms with higher catalytic activity than those found on flat sheets. A Taiwan-based team led by Han-Yu Hsueh from National Chung Hsing University, Taichung, and Rong-Ming Ho at National Tsing Hua University, Hsinchu, has applied this principle to introduce ‘single gyroid’ shapes—smooth and twisty channels arranged in a continues network—into nickel nano-catalysts. Previous attempts at producing porous materials have yielded materials with impractically broad pores. The researchers solved this problem by first seeding small amounts of palladium into gyroid-shaped polymer templates. The palladium nucleus helped nickel to be reduced smoothly inside the gyroid nanochannels. The resulting microspheres with nanoporous texture could catalyze organic chemical reactions with higher efficiency than commercial nickel sources. Well-defined metallic nanoporous sphere with single gyroid (SG) structure can be fabricated by simply using self-assembled diblock copol