Sunlight-Induced Synthesis of Various Gold Nanoparticles and Their Heterogeneous Catalytic Properties on a Paper-Based Substrate

Abstract

This work describes the light-induced preparation of various gold nanoparticles and demonstrates their possible use as efficient photothermal heating materials and practical heterogeneous catalysts under the irradiation of a solar-based light after being loaded onto a paper-based substrate. The synthesis of gold nanoparticles was accomplished under the irradiation of daily sunlight and a solar-simulated light with an intensity that was closely adjusted to the one-sun condition. Tunable sizes of gold nanoparticles were systematically controlled by the ratio of trisodium citrate and gold chloride ions, particularly with the solar-simulated light source. The size distribution and absorption properties of the resulting nanoparticles were thoroughly characterized by scanning electron microscope, dynamic light scattering, and UV-visible spectroscopy. The broad-band solar-based light sources were found to be efficient external stimuli to induce/enhance the formation of various gold nanoparticles at room temperature. As gold nanoparticles typically exhibit efficient light-induced heating properties due to their strong absorption bands, these nanoparticles were physically embedded on a filter paper to examine their photothermal heating properties and heterogeneous catalytic activity in the reduction of 4-nitrophenol under the irradiation of the solar-simulated light. As expected, the gold-loaded filter papers exhibited a systematic increase of temperature as a function of the gold nanoparticle concentration and enhanced catalytic property under the irradiation of the light, presumably caused by the photothermally induced heating property of the loaded gold nanoparticles. Overall, solar-based light sources can offer dual functions for the synthesis and application of metal nanoparticles possessing strong absorption bands.

Physico-Chemical Condition Optimization during Biosynthesis lead to development of Improved and Catalytically Efficient Gold Nano Particles

“…The functions of gold nanoparticles heavily rely upon their structure, size and morphology, so finding a way to modulate nanoparticles biosynthesis is an important aspect of the research8910. Shape and symmetry-dependent mechanical properties of metallic gold on the nanoscale has already been elucidated by Mahmoud et al 11.…”

Nanoparticle Synthesis by Biogenic Approach

“…This can be better understood by the fact that recently Bhaduri et al claimed Ag NP synthesis by sunlight [ 98 ]. Similarly, Kim et al showed sunlight based synthesis of gold nanoparticles [ 99 ]. Therefore, what we see here is some studies which claim to achieve the nanoparticle synthesis just like biogenic agents with no requirement of laborious microorganism screening, plant culturing/Soxhlet extraction, cultivating and complex downstream separation processing can be eliminated.…”

Advanced AuNMs as nanomedicine’s central goals capable of active targeting in both imaging and therapy in biomolecules

“…Noteworthy, some novel synthesis strategies, such as biosynthesis [52,53], 2D immiscible oil/water interface [54], levitated leidenfrost drop [55], sunlight-induced synthesis [56] and so on, have been reported, and such green and economic synthesis methods for preparation of uniform and controlled AuNMs provide the opportunity for development of low-cost and sustainable analytical techniques. However, the above technologies need to be further improved and standardized.…”