Photoluminescence and optical nonlinearity of CdS quantum dots synthesized in a functional copolymer hydrogel template

Abstract

The acrylic acid content in the copolymer influences the size of the CdS QDs as well as the linear and nonlinear optical properties of the copolymer.

Facile one-step fabrication of upconversion fluorescence carbon quantum dots anchored on graphene with enhanced nonlinear optical responses

“…For QDs, the generally accepted underlying OL mechanisms are two-photon and/or multiphoton absorption for pico-to femtosecond laser pulses and free-carrier absorption and/or NLS for nanosecond laser pulses. [19][20][21][35][36][37][38] By the closed-aperture Z-scan techniques, which can conveniently and effectively distinguish between NLA and NLR, it was conrmed that NLR made no contribution to the observed NLO and OL behavior of the CQD/GO hybrid in response to nanosecond laser irradiation in our experiments. To separate the contributions of NLA and NLS, we used a Z-scan setup following Joudrier and Rao 45,46 and the results are shown in Fig.…”

“…3 Extensive research has been performed on optical limiters in the past 20 years, and the strong OL properties of a wide range of materials have been intensively studied, from organic dyes (phthalocyanine, porphyrin, fullerene), [4][5][6][7][8][9] carbon nanomaterials (carbon black, carbon nanotubes, graphene) [10][11][12][13][14][15] to noble metal nanoparticles (NPs) [16][17][18] and quantum dots. [19][20][21] Typically, the occurrence of OL effects in materials arises from three main classes of mechanisms: nonlinear absorption (NLA), nonlinear scattering (NLS), and nonlinear refraction (NLR).…”

Динамика наведенного поглощения и нелинейно-оптический отклик в коллоидных квантовых точках Ag-=SUB=-2-=/SUB=-S

“…Размерная зависимость спектрально-люминесцентных свойств КТ определяет возможность настройки на резонанс между длиной волны падающего изучения и энергией соответствующего перехода, что позволяет в некоторых случаях снизить порог наступления нелинейнооптического отклика. Поэтому перспективным оказы-вается создание КТ, обладающих определенным набором локализованных состояний, заселение которых сопровождается обратным насыщающимся поглощением (ОНП) [12,19] или нелинейным преломлением из-за изменения заселенностей уровней энергии [20].…”

Tetrapolymer Network Hydrogels via Gum Ghatti-Grafted and N–H/C–H-Activated Allocation of Monomers for Composition-Dependent Superadsorption of Metal Ions

“…In this regard, several works were devoted to produce natural polymer-based hydrogels containing pectin, guar gum, , chitosan, xanthan gum, agarose, wheat bran, and GGTI . Similarly, several homo-, co-, ter-, and tetrapolymeric hydrogels were already reported for drug delivery and water treatment. − The mechanical weakness and fragility of homo-/copolymers could be surmounted by using ter-/multipolymer hydrogels, which offer improvement in the hydrogel structure and provide high mechanical strength and enhanced sensitivity toward physical and chemical stimuli. In this context, few researchers have synthesized tetrablock polymers by ex situ incorporation of four monomers. − For the first time, the synthesis of a natural polymer-grafted tetrapolymeric IPN using only two monomers and in situ auxiliary protrusion of NMPAP and AMP monomers, via N–H and C–H activations during solution polymerization, has been reported.…”