Microwave Shock Synthesis of Porous 2D Non‐Layered Transition Metal Carbides for Efficient Hydrogen Evolution

ABSTRACT Transition metal carbides (TMCs) serve as efficient catalysts for electrocatalytic hydrogen evolution reactions (HERs), holding significant importance in promoting hydrogen production for carbon neutrality. To optimize interfacial catalytic activity, structurally designing TMCs into two‐dimensional (2D) and porous structures to expose more practical surface areas and enhance electronic configurations is a common and effective strategy. Particularly, porous 2D non‐layered TMCs (2D NL‐TMCs) demonstrate richer active sites distinct from layered interfacial inertness. However, mainstream selective etching and chemical deposition growth mechanisms struggle to prepare highly active porous 2D NL‐TMCs due to constraints posed by their high structural strength and formation temperature. Herein, we successfully synthesized porous 2D W 2 C (2D p‐W 2 C) rapidly using a microwave shock method. Mechanistic verification reveals that leveraging transient high temperature and rapid on‐off properties of microwave effectively combines with an oxidation‐induced porosity mechanism, facilitating the evolution of porous 2D structures. These low‐dimensional nanostructures with abundant edge defect sites aid in efficient adsorption reactions of intermediate species in HER. Moreover, the successful preparation of a series of porous 2D NL‐TMCs (Mo 2 C, NbC, TaC) confirms the universality of this method, with the synthesized 2D p‐W 2 C exhibiting optimal HER performance. This strategy offers new insights into the topological synthesis of porous 2D NL crystals.