Preparation of Ordered Platinum Nanowires Array with Ultra‐High Length‐Diameter Ratio Using Electrohydrodynamic Jet Printing and Pyrolytic Reduction

Abstract Platinum nanowires (Pt‐NWs) and their arrays are critical metallic materials for the fabrication of functional structures and circuit interconnections in microsensors and microelectronic circuits. Currently, the preparation of Pt‐NWs is mainly based on electron beam lithography and electrochemical growth methods, which are hindered by complex process flows, low length‐diameter ratios, and disordered products. In this study, an effective method is proposed to prepare an ordered Pt‐NWs array with ultra‐high length‐diameter ratio using electrohydrodynamic jet (E‐Jet) printing and pyrolytic reduction. The ordered micrometer/sub‐micrometer platinum precursor fibers (Pt‐PFs) are first deposited by E‐Jet printing, then followed by a one‐step heat treatment to facilitate diameter shrinkage of the Pt‐PFs and precursor reduction to produce Pt‐NWs. This method is used to prepare long, straight, and continuous Pt‐NWs with diameters as low as 77 nm and length‐diameter ratios exceeding 10 ⁴ , and ordered Pt‐NWs arrays, grids, and suspended Pt‐NWs are also obtained. This study provides a new method for the controllable preparation of metallic nanostructures, which can be widely used in the manufacturing of high‐performance micro‐nano devices.