<abstract abstract-type="toc"> <title> <x xml:space="preserve">Abstract</x> </title> <p> <graphic position="anchor" id="ga" xlink:href="ark:/27927/pgj26b8jsgn" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" />An easily scaled-up 3D CoSe<sub>2</sub>/CFF hierarchical electrode has been developed as a highly active and stable hydrogen evolution reaction cathode.</p> </abstract>