Ni‐based Plasmonic/Magnetic Nanostructures as Efficient Light Absorbers for Steam Generation

Abstract

Solar steam generation technologies have gained increasing attention due to their great potential for clean water generation with low energy consumption. The rational design of a light absorber that can maximize solar energy utilization is therefore of great importance. Here, the synthesis of Ni@C@SiO2 core–shell nanoparticles as promising light absorbers for steam generation by taking advantage of the plasmonic excitation of Ni nanoparticles, the broadband absorption of carbon, and the protective function and hydrophilic property of silica is reported. The nanoparticle‐based evaporator shows an excellent photothermal efficiency of 91.2%, with an evaporation rate of 1.67 kg m−2 h−1. The performance can be further enhanced by incorporating the nanoparticles into a polyvinyl alcohol hydrogel to make a composite film. In addition, utilizing the magnetic property of the core–shell particles allows the creation of surface texture in the film by applying an external magnetic field, which helps increase surface roughness and further boost the evaporation rate to as high as 2.25 kg m−2 h−1.

Dual‐Zone Photothermal Evaporator for Antisalt Accumulation and Highly Efficient Solar Steam Generation

“…[ 5–16 ] Over the past several years, great progress has been made to improve energy efficiency of solar steam generation to boost the evaporation rate and clean water production. [ 17–50 ]…”

Plasmonic Nanostructures for Photothermal Conversion

“…Unlike aluminum, the oxide layer on the Ni particle surface cannot prevent further oxidation; therefore, the stabilization of nanoparticles is the key to real‐life applications. [ 136 ] Many methods have been demonstrated to coat the Ni nanoparticles with Al 2 O 3 or densified SiO 2 to enhance the stability of Ni nanoparticles against oxidation. [ 137–139 ] As we have demonstrated, Ni nanoparticles produced in colloidal methods were coated with SiO 2 via the Stöber method ( Figure a).…”

Confinement Capillarity of Thin Coating for Boosting Solar‐Driven Water Evaporation

“…Until now, two main strategies are usually utilized to increase the evaporation rate and efficiency of interfacial solar‐driven evaporation process. [ 7,9 ] The first is to develop photothermal materials with a high spectral absorption across the entire solar spectrum, including metallic materials, [ 10–16 ] semiconductors, [ 17–20 ] polymer, [ 21–26 ] and carbonaceous materials. [ 27–35 ] The second is to design 3D evaporator to maximize the use of heat or increase the surface area.…”