Universal and large-scale transform engineering from commercial metals to micron/nanoporous metals via an induced oxidation-reduction reaction

An innovative gaseous oxidization-reduction (GOR) method was proposed, which directly various transforms commercial transition metals/alloys into 3D micron/nanoporous forms. [Display omitted] •An innovative GOR method is proposed to directly transform metals/alloys into 3D nanoporous forms.•The method avoids the introduction of sacrificial materials, which is facile and cost-effective.•The method is applicable to various transition metals and alloys in different sizes and shapes.•The method enables the large-scale production of nanoporous metals.•The obtained nanoporous Ni/Ni alloys exhibit excellent catalytic performance for HER. Three-dimensional (3D) nanoporous metals are being increasingly utilized in various fields such as catalysis, energy storage, and sensing. However, the conventional fabrication approaches for 3D nanoporous metals, such as dealloying and template methods, require additional sacrificial materials and multiple fabrication steps and generate chemical waste. Herein, we propose a novel gaseous (O2 and H2) oxidation-reduction (GOR) method to directly transform various transition metals/alloys into 3D micron/nanoporous materials by utilizing the spontaneous reconstruction of metallic atoms. This method eliminates the need for sacrificial materials and acidic/alkaline solutions, making it facile, cost-effective, and environmentally friendly. The resulting micron/nanoporous Ni/Ni alloy exhibits excellent mechanical properties, atomic hydrogen adsorption capability, and hydrophilicity, leading to outstanding electrocatalytic activity and durability for hydrogen evolution reaction.