Effect of size and chemical composition of graphene oxide nanoparticles on optical absorption cross-section

Abstract

Photothermal therapy with various nanoparticles, as photothermal transducers, is a widely researched technique. A continuous wave (CW) laser is employed during this procedure. The therapeutic setup is slightly modified to measure the optical absorption cross-section of the graphene oxide (GO), by mitigating the effects of heat diffusion and light scattering. With an 808-nm CW laser setup modulated by a waveform modulation setup, the effect of nanoparticle size and composition of GO in water on optical absorption cross section is characterized.

Influence of graphene oxide's characteristics on the fabrication and performance of crosslinked nanofiltration membranes

“…It has been reported that suspensions containing smaller GO sheets may increase light absorption [43], which is in agreement with our findings, as an inverse relation between the absorbance coefficient and lateral size has been found (Figure 2). The optical absorbance in the visible region is enhanced with the sonication time, increasing the absorption coefficient from 670 to 830 ml mg -1 m -1 .…”

“…The samples were further examined via UV-Vis absorption spectroscopy. Though a cumulative combination of factors (such as the number of layers and surface chemistry) also affect UV-Vis absorbance, GO lateral-size is a key factor [43]. The absorbance of suspensions has been quantified by the determination of the absorbance coefficient (α) using the Lambert-Beer law (Eq.…”

Advances in photothermal regulation strategies: from efficient solar heating to daytime passive cooling

“…135 By studying the absorption cross section of graphene oxide (GO) nanoparticles, it was found that less energy is available for absorption when scattering increases and that larger nanoparticles usually have relatively low absorption coefficients. 136 Wang et al demonstrated a seed-mediated approach for the synthesis of ultra-stable plasmonic Cu–Au core–shell nanoparticles, where the Cu-based nanoparticles were stabilized with Au by controlling the reaction conditions, leading to significantly enhanced chemical stability. Compared to Au nanoparticles, Cu–Au nanoparticles exhibited superior photothermal conversion while being cost-effective.…”

The Effect of GO/TiO_2 Thin Film During Photodegradation of Methylene Blue Dye

“…In contrast, at a wavelength of 380 nm GO5 increased the absorption to about 1.7 (arbitrary unit). The adsorption of light was significantly affected by the addition of GO 35) . The samples with the addition of GO show high adsorption in the UV range.…”