Corrosion‐Mediated Self‐Assembly (CMSA): Direct Writing Towards Sculpturing of 3D Tunable Functional Nanostructures

Inexpensive and readily available metal foils have been extracted and sculptured into nanocomposites without the expense of applied energy. The unwanted corrosion phenomenon has been contrarily utilized to realize desirable 3D nanostructures through a corrosion‐mediated self‐assembly (CMSA) method, which is unattainable by conventional 2D patterning routes. By virtue of electrochemical dissolution/re‐deposition initiated by brass corrosion, ionic derivatives (Zn²⁺ and Cu²⁺) are continuously supplied and seized by etchant ions (PO₄^3?) to self‐assemble into well‐defined nanocomposites. Beyond 3D geometry patterning, CMSA enables arbitrarily tailoring of structures and chemical compositions with in situ multiphase amalgamation of hybrid materials, which improves homogeneity and thus mitigates phase separation issues. Importantly, the CMSA technique is demonstrated on transition metals for functional photocatalytic applications.