Advanced porous gold nanofibers for highly efficient and stable molecular sensing platforms

Porous gold nanofibers are fabricated through templated electrochemical routes in porous alumina membranes. Gold-silver alloy is electrochemically deposited in the nanocylinders of the porous alumina templates and then the silver phase is selectively dealloyed. The resulting nanofibers present a nanoporous network with a pore dimension of ∼10 nm and notable surface-enhanced Raman scattering (SERS) efficiencies which are at least seven times higher than from the smooth solid gold nanofibers without porosity. The relative SERS enhancement on porous gold is directly proved by imaging with a Raman microscope for conjugated porous gold/solid gold single nanorods.