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Herein, three polypyrrole-based nanohybrids were designed and prepared via a nucleophilic substitution reaction, i.e., peripherally substituted porphyrin-functionalized PPy (TPP-PPy), axially coordinated metal-porphyrin-functionalized PPy (SnTPP-PPy), and polypyrrole ternary nanohybrids co-functionalized with peripherally substituted porphyrins and axially coordinated metal-porphyrins (TPP-PPy-SnTPP). The TPP-PPy, SnTPP-PPy and TPP-PPy-SnTPP nanohybrids exhibited improved nonlinear optical and optical limiting performances when compared to the individual PPy and porphyrins under 4 ns, 532 nm laser pulses. Their improved optical nonlinearities were ascribed to a combination of mechanisms and efficient charge transfer effect between the porphyrins and PPy. The charge transfer effect between the porphyrins and PPy was confirmed by UV-vis absorption, fluorescence and electrochemical impedance spectroscopy. The TPP-PPy-SnTPP ternary nanohybrid exhibited the best nonlinear absorption, nonlinear refraction and optical limiting performances because of more effective charge transfer effect, which provides a new avenue for the development of polypyrrole–porphyrin systems in the fields of nonlinear optics and optoelectronic devices. [ABSTRACT FROM AUTHOR]

An organic-inorganic nanohybrid material (TPPOH-GO) is produced by linking monohydroxyporphyrin (TPPOH) and graphene oxide (GO) together via the ester bond, and the formation of this nanohybrid has been affirmed by various spectroscopy techniques. Nonlinear optical (NLO) and optical limiting (OL) performances were studied by the Z-scan technique. Because of the efficient electric charge transfer efficiency between TPPOH and GO, the as-prepared TPPOH-GO nanohybrid exhibits superior NLO and OL performances compared to those of TPPOH and GO. The photophysical, NLO and OL performances of hydrothermally reduced materials (TPPOH-RGO 1, TPPOH-RGO 2, TPPOH-RGO 3) are tuned by controlling the hydrothermal temperatures, implying the scope of using them as optical limiters. • The hybrid material that the porphyrin is covalently linked to GO is reduced for the first time. • Significantly enhanced optical nonlinearity was observed for the material being reduced. • The enhanced performance is ascribed to efficient charge transfer. [ABSTRACT FROM AUTHOR]

Abstract Nonlinear optical nanostructured materials are gaining increased interest as optical limiters for various applications. In the present case, two soluble porphyrins (TPP) covalently functionalized hexagonal boron nitride (h-BN) nanohybrids (BN-TPP 1 and BN-TPP 2) as optical limiter were prepared for the first time, and characterized by various spectroscopic techniques. The covalent attachment of porphyrins onto the surfaces of h-BN improves the ease of processing of these BN-porphyrins composite materials. The results of Z-scan measurements at 532 nm in the nanosecond laser pulse regime indicated that the BN-TPP nanohybrids exhibited markedly improved nonlinear absorption and optical limiting performances compared to a control sample consisting of a covalently unattached physical blend of h-BN and porphyrins, and the porphyrin covalently functionalized graphene nanohybrids, as well as to either h-BN or TPP alone. The enhanced optical nonlinearities can be ascribed to the synergetic effects originating from charge transfer between the two counterparts. The effects of porphyrins on the structure, thermal, linear and nonlinear optical responses of the h-BN were investigated in detail. The efficient nonlinear optical performances make the as-prepared nanohybrids excellent candidates for optical limiting applications. Highlights • Porphyrins covalently functionalized boron nitride is prepared for the first time. • The solubility of boron nitride is improved by the introduction of porphyrins. • Significantly enhanced optical nonlinearity is observed for the obtained hybrids. • The improved performance is ascribed to the synergetic effects. [ABSTRACT FROM AUTHOR]

Abstract To improve the dispersibility of single walled carbon nanotube (SWCNT) in common organic solvents and adjust its photoelectronic performance, two methacrylate-co-porphyrins covalently functionalized SWCNT nanohybrids (SWCNT-TPP 1 and SWCNT-TPP 2) were prepared by radical polymerization. This attachment of porphyrins onto the surface of SWCNT significantly improves their solubility and dispersion stability of the SWCNT-based materials in organic solvents. The electronic interactions between porphyrins and SWCNT were investigated by the UV–vis, fluorescence and Raman spectroscopic methods. Z-scan measurements suggested that both nanohybrids exhibited increased nonlinear absorption and optical limiting performances compared to the separate SWCNT and porphyrins, which can be ascribed to the synergetic effects originating from the charge transfer effect between the two counterparts. The best optical limiting performance is observed for SWCNT-TPP 1 due to more effective charge transfer effect in comparison with those of other samples. These results suggest that the radical polymerization is a useful approach towards the rational design of solution-processible yet stable optical limiting materials, and this concept may be readily extended to other directional optoelectronic properties. Highlights • Two methacrylate-co-porphyrins covalently functionalized SWCNT were prepared. • The solubility and dispersion stability of the SWCNT were improved. • The enhanced optical limiting was observed due to the efficient charge transfer. [ABSTRACT FROM AUTHOR]

Considerable attention has been paid to design multifunctional hybrid materials for developing novel optoelectronic systems. Here, a series of novel porphyrin decorated Bi 2 O 2 CO 3 nanocomposites (BOC/TPP) loaded with different porphyrin contents was prepared by a facile solvothermal technique to maximize the photocatalysis and optical nonlinearity. The photoresponsive range of the BOC/TPP nanocomposites can be extended from UV to visible light, and the band gap can be continuously tuned. The wide absorption of the as-prepared nanocomposites in the visible light region makes them suitable for photocatalytic and nonlinear transmission studies. The associated photocatalysis and optical nonlinearity for the BOC/TPP nanocomposites are shown to be dependent on the contents of porphyrin. Compared to BOC, TPP and other prepared nanocomposites with different TPP loadings, the BOC/0.03TPP nanocomposite with 3 wt% TPP exhibits the highest photocatalytic performance and nonlinear optical absorption effect, due to the efficient interfacial charge transfer and the strong interfacial electronic interactions between TPP and BOC. These findings provide an ideal scientific platform to guide the rational design of difunctional nanomaterials with desired optoelectronic performances. [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy) and its acid/base composites (PPy·H 2 SO 4 , PPy·HCl and PPy·NH 3 ·H 2 O) were successfully synthesized and were characterized respectively by using fourier transform infrared, ultraviolet/visible absorption, X-ray diffraction, transmission electron microscopy and Raman spectroscopic techniques. The nonlinear optical properties of PPy and its acid/base composites were investigated using nanosecond Z-scan measurements at 532 nm. At the identical linear transmittance, the saturable absorption of pure PPy was changed to reverse saturable absorption by doping with acid (HCl and H 2 SO 4 ) and base (NH 3 ·H 2 O). The possible mechanisms for the different nonlinear properties were also discussed. [ABSTRACT FROM AUTHOR]

A novel zinc porphyrin (ZnTPP) derivative bearing an E -stilbazole chromophore in the axial position (ZnTPPL) was designed and prepared. Z-scan studies reveal that this complex exhibits improved nonlinear optical absorption and refraction in comparison with ZnTPP. In addition, the molecular structure of the complex was determined by X-ray diffraction study. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (RGO) has been covalently functionalized with porphyrin moieties by two methods: A straightforward Prato reaction (i.e. a 1,3-dipolar cycloaddition) with sarcosine and a formyl-containing porphyrin, and a stepwise method that involves a 1,3-dipolar cycloaddition to the RGO surface using 4-hydroxybenzaldehyde, followed by nucleophilic substitution with an appropriate porphyrin. The chemical bonding of porphyrins to the RGO surface has been confirmed by ultraviolet/visible absorption, fluorescence, Fourier-transform infrared, and Raman spectroscopies, X-ray powder diffraction and X-ray photoelectron spectroscopy, transmission electron and atomic force microscopy, and thermogravimetric analysis; this chemical attachment assures efficient electron/energy transfer between RGO and the porphyrin, and affords improved optical nonlinearities compared to those of the RGO precursor and the pristine porphyrin. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Allyloxyporphyrin-functionalized multiwalled carbon nanotubes (MWCNT-TPP) were synthesized by radical polymerization and characterized by FTIR, UV/Vis absorption, and X-ray photoelectron spectroscopy; elemental analysis; TEM; and thermogravimetric analysis. Z-scan studies revealed that this nanohybrid exhibits enhanced nonlinear optical (NLO) properties compared to a control sample consisting of a covalently unattached physical blend of MWCNTs and porphyrin, as well as to the separate MWCNTs and porphyrin. At the wavelengths used, the mechanism of enhanced optical limiting likely involves reverse saturable absorption, nonlinear scattering, and photoinduced electron/energy transfer between the MWCNTs and the porphyrin. The role of electron/energy transfer in the NLO performance of MWCNT-TPP was investigated by Raman and fluorescence spectroscopy. [ABSTRACT FROM AUTHOR]

Two multi-walled carbon nanotube (MWCNT)-based nanohybrids, MWCNT-ZnTPP and MWCNT-TPP (TPP=5-[4-{2-(4-formylphenoxy)- ethyloxy}phenyl]-10,15,20-triphenylporphyrin, ZnTPP=5-[4-{(4-formylphenyl)ethynyl}phenyl]-10,15,20-triphenylporphinatozinc(II)), were prepared directly from pristine MWCNTs through 1,3-dipolar cycloaddition reactions. Covalent attachment of the porphyrins to the surfaces of the MWCNTs was confirmed by Fourier transform infrared spectroscopy, ultraviolet/visible absorption, fluorescence, Raman, and X-ray photoelectron spectroscopy, elemental analysis, transmission electron microscopy, and thermogravimetric analysis. Attachment of the porphyrin moieties to the surface of the MWCNTs significantly improves the solubility and ease of processing of these MWCNT-porphyrin composite materials. Z-scan studies reveal that these MWCNT-porphyrin nanohybrids exhibit enhanced nonlinear optical properties under both nanosecond and picosecond laser pulses at λ=532 nm in comparison with free MWCNTs and the free porphyrin chromophores, whereas superior optical limiting performance was displayed by MWCNT-porphyrin composite materials rather than MWCNTs/ZnTPP and MWCNTs/TPP blends, which is consistent with a remarkable accumulation effect as a result of the covalent linkage between the porphyrin and the MWCNTs. [ABSTRACT FROM AUTHOR]

Porphyrin‐functionalized multi‐walled carbon nanotubes (MWCNTs) have been prepared through 1,3‐dipolar cycloaddition reactions. Covalent attachment of porphyrins to the MWCNTs' surfaces affords composite materials with excellent solubility and facile processing. These MWCNT–porphyrin nanohybrids exhibit strong optical limiting of both nanosecond and picosecond laser pulses at 532 nm, attributed to a combination of nonlinear scattering, reverse saturable absorption, and photoinduced energy transfer. For more information, see the Full Paper by C. Zhang et al. on page 14159 ff. [ABSTRACT FROM AUTHOR]