Optical Limiting of Carboxyl–Graphene Oxide

Abstract

Using the Z-scan method, the nonlinear optical (NLO) absorption property of carboxyl-functionalized graphene oxide (GO) was researched for the first time. The strong optical limiting (OL) effect was found in carboxyl-GO, which can be attributed to the two-photon absorption (2PA). At 532 nm excitation condition, the threshold of optical limiting behavior is only 8% of that at 1064 nm excitation, and the saturable intensity I s as well as the 2PA coefficient β 2 are 1.31 GW/cm 2 , 0.17 cm/GW, respectively. It indicates that carboxyl-GO is an excellent nano-material for optical limiting application, especially in short wavelength scope.

<p>Development of a bioaffinity SPR immunosensor based on functionalized graphene oxide for the detection of pregnancy-associated plasma protein A2 in human plasma</p>

“…We used the refractive index (n) and extinction coefficient (k) at a wavelength of 690 nm corresponding to Cr, Au, and Cys films, and obtained 3.797+i4.368, 0.116+i3.817, and 1.45+i0, respectively 35. The use of 1 g/l concentration of carboxyl-GO resulted in a film with a thickness of 3 nm of a self-assembled monolayer (SAM) composition 36. Using these parameters and the measurement results in Figure 4A in Fresnel’s equations for a multilayer theory, the carboxyl-GO film refractive index was 1.673 29.…”

Facile synthesis of hierarchical porous carbon derived from carboxyl graphene oxide/phenolic foam for high performance supercapacitors

“…20 In each FTIR spectrum, there was a wide and strong absorption peak at 3440 cm À1 , which could be considered as the contribution of the -OH groups residual in phenol and graphene. 20,54 The characteristic peak at 1326 cm À1 was mainly contributed by C-O vibration, and the one at 1630 cm À1 corresponded to the C]C vibration. 55,56 In the FTIR spectra of RGPF-0.20%-800, a weak absorption peak was observed at 2340 cm À1 , which could be attributed to the residual O-C]O groups formed by the esterication reaction between carboxyl graphene oxide and phenolic resin.…”

“…In addition, compared with CGO and phenolic resin, 57,58 the peaks owing to the oxygen groups such as C]O (1732 cm À1 ) and C-O-C (1048 cm À1 ) disappeared, indicating these oxygen groups were decomposed during the carbonization, which is helpful for the pore formation. 54 Raman spectroscopy is an effective tool for the characterization of carbon materials. As shown in Fig.…”