A Novel Ink‐Stained Paper for Solar Heavy Metal Treatment and Desalination

Abstract

High‐performance, flexible and non‐toxic ink‐stained paper is successfully prepared by a two‐step ultrasonic process. Owing to the superior features of light absorption, wettability and heat management via our homemade mimetic tree system, the prepared ink‐stained paper‐black with an average pore size of 2 µm (ISP 2 ‐Black) shows outstanding steam generation performance (85.8% for 1.25 kg m −2 h −1 and 85.5% for 3.70 kg m −2 h −1 at 1 and 3 suns, respectively), and good durability. Furthermore, an outdoor prototype system is realized by fresh water generation up to 1.24 kg m −2 d −1 for direct solar steam generation. Moreover, the ISP 2 ‐Black also exhibits good performance in solar heavy metal treatment and desalination. This work provides a facile method to fabricate ink‐stained paper and a practical route for more cost‐efficient fresh water production and wastewater/polluted water treatment.