The accuracy of data collected by optical instruments can be greatly impacted by radar band electromagnetic waves (EM) and scattered visible light. Traditional electromagnetic-wave-absorbing (EMA) materials face challenges in effectively attenuating electromagnetic waves within the visible light spectrum. To address this issue, a structural engineering-based assembly strategy was developed to construct PVDF/Ti 3 CNT x @PPyNF composites with multiple heterogeneous interfaces, inspired by snake scales. And through the self-doping of N elements and the coating process, the material finally exhibits excellent microwave and visible light absorption properties. This approach generates multiple polarization losses of electromagnetic waves, enabling the material to exhibit excellent electromagnetic wave absorption performance. Specifically, the PVDF/Ti 3 CNT x @PPyNF composite, containing 5 wt % Ti 3 CNT x @PPyNFs, demonstrates exceptional microwave absorption performance, with a minimum reflection loss of −65.5 dB and an effective absorption bandwidth of up to 6.95 GHz. Additionally, the composite coating exhibits 97.4% visible light absorption performance, providing a promising solution to the challenges of protecting against complex electromagnetic environments.

No abstract

Solar vapor generation (SVG) has become a promising and sustainable technology for water purification and desalination. Recently, porous hydrogel-based solar evaporators that combine reduced water evaporation enthalpy and adequate water replenishment have demonstrated a highly effective SVG performance. However, it remains challenging to realize rapid and low-cost fabrication of porous hydrogel evaporators for practical applications. Herein, we report a facile and rapid method (photoinduced polymerization, c.a. 15 s) to fabricate porous composite hydrogels for effective solar seawater evaporation without time-consuming modification and post-treatment. The hydrogel evaporators show laminated composite structures that consist of carbon fiber felt for solar harvesting and an open microporous polyacrylamide-co-poly(N-isopropyl acrylamide) (PAM-co-PNIPAAm) hydrogel for water transport. After composition with photothermal carbon fiber felt (CFF), the CFF/PAM-co-PNIPAAm composite hydrogel evaporators exhibit rapid photothermal heating, in conjunction with the reduced water evaporation enthalpy and continuous water supply for solar evaporation, enabling an evaporation rate of 1.34 kg m −2 h −1 from 3.5 wt % NaCl solution under one sun irradiation, which approaches the theoretical evaporation rate limit of 2D evaporators (1.46 kg m −2 h −1 ). It is expected that the simple and fast fabrication method presented in this study, without the typical need for expensive raw materials and tedious procedures, will promote the application of hydrogel solar evaporators for water purification.