etc. Macroscopic metal grids have been successfully developed and used as a front electrode for inorganic solar cells and are a potential replacement of thin metal films as transparent electrode (TE) in organic optoelectronic devices also. [19] They exhibit high visible light transparency due to the large open area between the thick lines of metals and high conductivity due to the continuity of mesh with metal lines crossing each other and reduced junction resistance. Tuning of the work function is also possible by selecting the metal. [20] Photolithography, nanolithography, or transfer printing methods have been employed to develop metal grid electrodes, which however are complicated and tedious processes. [21,22] Metal nanowires-based 1D network shows the high merit of optical and electrical properties on becoming an excellent transparent conducting electrode, but suffer from certain limitations such as rough surface finish, poor adhesion properties, change in properties with temperature variation. The bare Ag NW suffers from oxidation and melting issues when exposed to temperature and air during device fabrication and application. The best possible solution is to cover such a structure with high refractive index n-type materials with high thermal stability. The metal oxide is a suitable candidate to combine with such nanostructures. Hybrid structures (dielectric/metal NW/dielectric, DMD) have been used to resolve these issues. [3] Here, metal governs the electrical while dielectric layer improves optical properties of the hybrid structure. [23] This conventional DMD structure possesses adequate transparency in the visible region. These DMD structures due to high transparency and sufficient conductivity show great promise for their potential use in next-generation optoelectronic and energy devices. [24] Metal mesh is preferred over nanowires/macrowires because of less contact and junction resistance. [25] There are few reports of fabrication of metal nanostructure using soft lithography [9] and leaf structure [25] for energy and optoelectronics applications. [26] However, an extensive investigation is needed to test the structural properties and stability over a wide temperature range of such structures.The present research work reports the fabrication and study of bioinspired metal grid electrode. The electrode exhibits better, 1D metal network is one of the promising alternatives of the conventional transparent conducting electrode (TCE) viz ITO/FTO. Bioinspired fabrication of junction resistance free metal grid structures is explored for their TCE applications. The leaf-based metal grid electrodes exhibit low DC resistivity (10 −5 -10 −4 Ω cm) and high optical transparency (80-90%) in the visible spectrum. The leaf vein structures are varied to obtain better optoelectronic properties. Finally, a multilayered stacked structure (SnO 2 -Ag-Au-SnO 2 ) is deposited on a poly ethyl terephthalate substrate and low-to high-temperature electrical stability is demonstrated. X-ray photoelectron spectroscopy results are...

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