Nonlinear Optical Transmission of Nanographene and Its Composites

Abstract

The effects of the amount of nanographene on physical, mechanical, and thermal properties and morphology of the wood-plastic composites were investigated. This wood-plastic was made using recycled high density polyethylene (HDPE), nanographene, and wood flour. Four weight levels, 0, 0.5, 1.5, or 2.5 wt.% of nanographene, were combined with 70% polymeric matrix and 30% lignocellulosic material with an internal mixer. The results showed that by increasing the amount of nanographene up to 0.5% by weight, the flexural strength, flexural modulus, and notched impact strength of the composite increased. After adding 2.5 wt.% nanographene, these properties were reduced. By increasing the amount of nanographene, both the amount of residual ash and the thermal stability increased. Study of the images from scanning electron microscope (SEM) showed that the samples containing 0.5% of nanographene had less pores and were smoother than other samples.

Nonlinear optical transmission of cyanobacteria-derived optical materials

“…After cooling, the black substance, PCYB was collected. About 1 mg of PCYB were dispersed into 5 mL of dsDNA solution (2 mg dsDNA/mL) in pH 8.0 Tris buffer [15,39,40] and 5 mL of 1 wt% SDS aqueous solution [15,41,42], respectively, with an aid of sonication in a Branson 1510 ultrasonicator. For benchmark optical limiting standards, a saturated C 60 solution was prepared in toluene, and carbon black ($0.1 mg) was dispersed into 5 mL of 1 wt% SDS aqueous solution with the assistance of sonication.…”

“…For optical limiting measurements, the laser system used in the experiments was a Continuum Powerlite Precision II Series Model 8000 Injection Seeded Nd: YAG nanosecond pulsed laser with 8 ns pulse duration and k = 1064.2 nm output [15]. The laser was used to pump two LaserVision optical parametric oscillators and optical parametric amplifier systems to generate two adjustable laser beams covering 532 nm, 710-910 nm, and 1.06-5 lm [43][44][45][46].…”

“…[15]. The transmittance T was then measured as a function of laser incident fluence, at least 3 times at each input fluence for each sample.…”

“…The current optical limiting materials include C 60 solution in toluene [10,11] and carbon black aqueous suspension [13,14], which are the benchmark standards of optical limiting materials [11]. However, they have some disadvantages [15]. Carbon black suspension is unstable and tends to form aggregates.…”

“…However, in view of the fact that cyanobacteria also contain a high carbon level in the pigment molecules and cell walls, when carbonized, they might form unique carbon nanostructures. These carbon nanostructure-based composites might have superior nonlinear optical properties as carbon nanotubes [11,26,27] and graphene [15,[28][29][30][31][32][33] do, and might be used as a low cost broadband limiter. To our knowledge, however, no systematic work has been done to explore this opportunity.…”