Solar steam generation (SSG) is promising for clean water production owing to low cost, simple operation, and green technology. This work investigates the fabrication of bioinspired photothermal (BIPT) material by sputtering a copper layer on Phanera purpurea (PP) leaf for application in SSG systems. It is observed that the light absorbance of the BIPT material exceeds 92% in the wavelength region of 300–2500 nm. This is due to the light trapping effect caused by multi‐internal reflection inside the Cu‐coated leaf nanostructure. The BIPT material exhibits a low thermal conductivity and easy cleaning properties as a result of PP leaf surface features. A novel strategy in this work is the design of the BIPT material‐based SSG system to recycle the radiative heat loss for evaporation. The developed SSG system results in a solar steam efficiency of 83.7% and a water evaporation rate of 1.45 kg m−2 h−1 under 1 sun. It is also applied in seawater desalination and the produced water satisfies the WHO standards for ion concentrations in clean water. Because of the simple procedure and low cost, the sputtering Cu on the PP leaf can be potentially used in the mass production of BIPT material for seawater desalination.

& tien thanh pham 1* in this work, two copper-based biometamaterials were engineered using leaves of water cabbage (Pistia stratiotes) and purple bauhinia (Phanera purpurea) as templates. the copper sputtering was implemented to produce a thin copper film on the surface of leaves. The scanning electron microscopy (SeM) images exhibited the root hair-like nanostructure of water cabbage leaf and single comb-like nanostructure of purple bauhinia leaf. in spite of copper coating, the leaf surfaces of water cabbage and purple bauhinia were black and exhibited excellent light absorption at visible and near infrarrred wavelengths. It was estimated that these two types of leaves could absorb roughly 90% of light. Finite-difference time-domain (FDTD) calculations predicted the low reflectance stemming from the leaf nanostructures and copper coating layer. Because of the low cost of copper as a coating metal and simple procedure, this can be a promising method for quick fabrication of a thin copper film on the leaf nanostructure for application in blackbody or as the light absorbers.