| With the development of modern society,environmental and safety issues have increasingly become the focus of social attention.Traditional solutions are often characterized by high energy consumption,high pollution,and low reliability,which are not in line with the path of sustainable development.In recent years,with the rapid development of nanotechnology,people's understanding and research on nanomaterials have also made great progress.Among them,plasmonic materials represented by gold,silver and copper have received extensive attention from scientists due to their excellent physical and chemical properties.The free electrons of precious metal(gold,silver,copper)nanoparticles will oscillate under the irradiation of incident light.When the position of the electron deviates from the nucleus,the Coulomb attraction between the nucleus and the electron will cause the collective oscillation of free electrons,which will form a localized surface plasmon resonance(LSPR),which will cause strong optical absorption and It scatters the far field and produces a very strong electric field around the nano-particles in the near field.It is widely used in biomedicine,optoelectronics and other fields.However,the application of the above-mentioned plasmon resonance materials to the engineering field still faces many challenges,especially in the near-infrared region,problems such as excessively long bandwidth and low responsivity are common.This article focuses on improving the near-infrared photothermal performance of plasmon resonance materials,based on the hotspot theory,with three nanostructures as the research object(Cu S semiconductor,silver nanosheet,gold-copper nanoalloy),combined with the reaction in the process of seed synthesis The adjustment of the conditions,the generation of nanocrystals with different"hot spots",the enhancement of the photothermal properties of the material,and the application of scattering theory and other methods to study the local surface plasmon resonance characteristics of the particles,and discuss the structure changes on the particle plasmon resonance The influence of characteristics,and the physical and chemical connotation of the research results are elaborated and analyzed.The main research contents and results are as follows:1.In the process of synthesizing silver nanosheets by the seed-mediated method,the reaction conditions were adjusted to generate cracked nanosheets.Due to the local electric field enhancement effect of the cracked nanosheets,more local hot spots were generated.Compared with traditional triangular nanosheets,it has stronger light and heat performance.And using the discrete dipole approximation method(DDA)calculation,revealed the linear relationship between the shape of the nanosheet and its near-infrared absorption.When applied to the field of laser detonation,the reliability and safety of laser detonation are significantly improved.2.This article introduces the controllable synthesis and formation mechanism of gold-copper alloy materials.The five-pointed star-shaped gold-copper alloy nanoparticles were produced.The study of the growth mechanism revealed that the nanocrystals were obtained from decahedral crystal nuclei that grew along the twin boundaries.This pentagram gold-copper alloy is rich in angularity and near-infrared absorption enhancement,and it is applied to the field of laser detonation,which significantly reduces the initiation threshold and delay time of low-sensitivity explosives.3.Using konjac as the substrate,adding copper sulfide nanoparticles,using methods such as directional freezing and deacetylation.Made into ultra-light,highly elastic,hydrophilic sponge.It has the characteristics of reliability,low cost,and broad spectrum absorption.The porous structure of the sponge allows the sample to float on the water surface,and promotes light absorption and water transport,which is beneficial to enhance the water evaporation performance.The copper sulfide sponge sample effectively realizes the evaporation of water and the limited reduction of uranium.Under 1 sun,the evaporation rate of copper sulfide sponge water is 1.582 kg·m-2·h-1,the evaporation efficiency is 92%,and the adsorption of uranium can reach 350 mg/g.Both showed excellent performance in the test.The condensate treated by the copper sulfide sponge meets the national drinking water standard and has a good application prospect in the treatment of uranium-containing wastewater.Aiming at the problems of low photothermal conversion efficiency of plasmon resonance nanomaterials and insufficient near-infrared absorbance,based on the"hot spot theory"of local electric field enhancement,a batch of nanometers rich in sharp corners and cracks have been developed to control the reaction conditions.Crystals,in order to achieve strong near-infrared absorption and high light-to-heat conversion efficiency of plasmon resonance nanomaterials. |
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