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Novel tetracarboxylic zinc naphthalocyanine-graphene oxide (ZnNcC4-GO) and tetracarboxylic zinc naphthalocyanine-amino graphene oxide (ZnNcC4-NGO) hybrids have been prepared with a covalent functionalization method. A series of characterizations have been used to prove the structures of ZnNcC4-GO and ZnNcC4-NGO hybrids. The third order nonlinear optical properties were investigated using the Z-scan technique at 532 nm with 4 ns laser pulses. Either ZnNcC4-GO or ZnNcC4-NGO exhibited much larger nonlinear optical absorption coefficients than GO and ZnNcC4 as a result of the covalent link between GO and ZnNcC4. ZnNcC4-NGO hybrids perform the enhanced NLO properties than ZnNcC4-GO, attributed to the increased excited state absorption from the extended sp2 carbon configurations of the NGO moiety in ZnNcC4-NGO hybrids along with the partial reduction of NGO nanosheets, and the stronger PET/ET process between NGO and ZnNcC4. Moreover, the Z-scan curve of ZnNcC4-NGO shows a deeper RSA valley and the larger β value compared to that of ZnPcC4-NGO because the π-conjugated system of ZnNcC4 is larger relative to that of ZnPcC4.

In this work, an ultrathin nanocomposite films containing tetracarboxylic Nickel (Ⅱ) naphthalocyanine (NiNc) and titania nanoparticles are fabricated through electrostatic self-assembled layer-by-layer (LBL) technique. UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) are utilized to characterize the film. The optical limiting properties of the composite films are investigated through intensity-dependent transmittance measurements at 600 nm with 18 ps laser pulses. The results show that the composite films have notable optical limiting response (β ∼ 5.4 × 10−7 m/W), which is strongly enhanced compared to both TiO2 and NiNc-only samples. Our results suggest that the nanocomposite films possess the potential for optical limiting applications in the phototherapeutic window.

Anodizing and post-treatment of aluminium alloys can effectively improve their surface corrosion resistance. In this work, we demonstrate the effectiveness a potassium permanganate sealing (M-S) treatment of tartaric‑sulfuric anodized 2024 aluminium alloy. This post anodic oxidation process was performed by immersing samples in the electrolyte solution at 70 °C for 30 min. Immersion and salt spray tests show such a M-S sealing processing can result in much improved corrosion resistance. The M-S treated samples can resist 240 h of salt spray test without corrosion pitting. Detailed morphological, microstructural and chemical analyses have been used to reveal mechanistic effects of the M-S retreatment. Interfacial electrochemical impedance measurements were performed to directly compare the corrosion behaviors of Al alloys after different post-treatments.

Zinc phthalocyanine carrying sulfenyl and 6-sulfydryl linkers was firstly used to functionalize with sulfur vacancies MoS2. The synthesized MoS2/ZnPc composite was further prepared to be PVA (polyvinyl alcohol) thin films by a drop coating method. The microscopic structures and photophysical properties of novel MoS2/ZnPc composite were characterized. A series of analysis results indicate that zinc phthalocyanine with sulfenyl and 6-sulfydryl linkers is loaded to sulfur vacancies of MoS2 by ligand conjugation. The third order nonlinear optical properties of MoS2/ZnPc composite were studied by an open aperture Z-scan technique at 532 nm with 4 ns laser pulses width. In comparison with individual MoS2 or ZnPc, whether MoS2/ZnPc solution or MoS2/ZnPc/PVA film sample possesses larger third order nonlinear absorption coefficients (β) and lower limiting thresholds (F50). It can be ascribed to a combination of different NLO absorption mechanisms for MoS2/ZnPc composite, including one-photon absorption, two photon absorptions and nonlinear scattering of MoS2, triplet excited state absorption of ZnPc, nonlinear scattering of MoS2/ZnPc and the photo-induced electron transfer or energy transfer (PET/ET) process between MoS2 and ZnPc moieties.

A series of tetra substituted phthalocyanines bearing 2-mercaptobenzimidazole or 2-mercaptobenzothiazole units with different central metals (Zn and In) were synthesized. Their photophysical properties including the parameters of fluorescence and triplet state were studied. The benzothiazole substituted phthalocyanines exhibit stronger third-order nonlinear optical properties (NLO) absorption effects, higher triplet quantum yield (ΦT) and faster intersystem crossing rate compared to the benzimidazole substituted phthalocyanines. With the same central metals, benzothiazole substituted phthalocyanine complexes have the lower fluorescence quantum yield (ΦF), the higher triplet quantum yield (ΦT) and the larger third-order NLO properties as a result of larger conjugated structure and spin-orbit coupling induced by sulphur atoms. The influences of the central metal atoms and the peripheral substituents on the third-order NLO properties are discussed using photophysical parameters.

WSe2/reduced graphene oxide (WSe2/rGO) composite has been synthesized by a facile solvothermal reaction and all the polyvinyl alcohol (PVA) films were prepared by simple drop casting method. The third order nonlinear optical (NLO) properties and optical limiting (OL) responses of WSe2/rGO solution and WSe2/rGO/PVA film were investigated using the Z-scan technique at 1064 nm and its second harmonic of 532 nm with 4 ns laser pulses. The results demonstrate that the third order NLO and optical limiting responses of the WSe2/rGO composite are significantly enhanced compared with WSe2, rGO and WSe2/GO composite, whether in the solution or in the PVA film. It can be attributed to the contribution of charge transfer process and synergistic effect between WSe2 and rGO moieties. Besides, the optical nonlinearity of WSe2/rGO/PVA film was larger than that of the WSe2/rGO solution. The WSe2/rGO/PVA film exhibits much larger nonlinear absorption coefficient (3.5 × 105 cm/GW) and much lower threshold value (0.25 J/cm2) with the input energy of 27 μJ at 532 nm. The results pave the way for the nonlinear optical properties with transition metal dichalcogenides (TMDs)/graphene composite in the optical limiting devices.

Herein, a series of tetra-α-isopentyloxyphthalocyanine copper, nickle, lead (CuPc-3, NiPc-3, PbPc-3) have been successfully bonded on the surface of acidified multi-walled carbon nanotubes (MWCNTs) by using a solution self-assembly method based on π–π stacking interaction facile reaction. The obtained MPc-3/MWCNTs (M = Cu, Ni, and Pb) hybrids display good dispersibility in DMF, which is beneficial to construct uniform sensing devices. The MPc-3/MWCNTs sensors exhibit excellent sensing performance, in terms of sensitivity, reversibility, reproducibility, selectivity and stability, especially CuPc-3/MWCNTs sensor in detail, the response is about 40.5% (80 ppm), the limit of detection is as low as 75 ppb, and the recovery time is about as fast as 180 s at room temperature. The enhanced NH3-sensing performance is mainly due to the synergistic effect between MPc-3 and MWCNTs, e.g. the stronger adsorption interaction of MPc-3 with NH3, the high electrical conductivity of MWCNTs, and the fast charge transfer between MPc-3 and MWCNTs. The systematic study developed here provides a valid way to fabricate high-efficient NH3 sensors.

Two kinds of metameric tetra-amino-phthalocyanine zinc (ZnTAPc) bearing peripherally and non-peripherally substituent groups connected to graphene oxide (GO) has been synthesized via covalent functionalized reaction. A series of characterizations including X-ray photoelectron spectroscopy, Fourier transform infrared spectra, Raman spectra, thermogravimetric analysis and ultraviolet–visible absorption confirm that the two kinds of ZnTAPc are grafted onto the GO nanosheets successfully. The fluorescence spectra show strong fluorescence quenching by the photo-induced electron transfer (PET) process between ZnTAPc moieties and GO nanosheets, and the possibility of the PET process has been further proved using the thermodynamic method. The nonlinear optical (NLO) properties of the two kinds of hybrid material were investigated using the Z-scan technique at the wavelength of 532 nm in the nanosecond scale. The GO-β-ZnTAPc hybrid possesses much stronger nonlinear absorption effect than GO-α-ZnTAPc hybrid, showing that the position of substituent have a significant influence on the NLO properties of aforementioned hybrids.

An ultrathin composite films containing cobalt phthalocyanine (CoPc) and poly(diallydimethyl ammonium chloride) (PDDA) were fabricated through layer-by-layer assembly technique. The resulting films were characterized by UV-Vis spectroscopy and atomic force microscopy. Their third-order nonlinear optical properties and photo-excitation dynamics were investigated with 20 ps laser pulses at 532 nm. The results demonstrate that the ultrathin films have notable third order optical nonlinearities (χ(3)∼4.7 × 10−9 (esu)) and fast excited-state relaxation (τ∼67 ± 6 ps), indicating their potential applications in future nonlinear optical devices.

Bismuth telluride/reduced graphene oxide (Bi2Te3/rGO composites) was prepared by solvent-thermal method, and Bi2Te3/rGO-PVA (Polyvinyl alcohol) thin film was synthesized from drop coating method. The third-order nonlinear optical properties (NLO) and optical limiting (OL) performances of the solution samples and the film samples were studied using Z-scan test at the laser wavelength of 532 nm and 1064 nm with 10 Hz repetition frequency and 4 ns pulse width. In comparison with Bi2Te3, rGO and Bi2Te3+rGO (Bi2Te3 and rGO are mechanically stirred together), whether Bi2Te3/rGO solution sample or Bi2Te3/rGO-PVA film sample possess larger third order nonlinear absorption coefficients (β) and lower limiting thresholds due to the charge transfer and synergistic effect between Bi2Te3 and rGO. The limiting thresholds of Bi2Te3/rGO-PVA thin film samples (~0.19 J/cm2 at 532 nm and ~0.52 J/cm2 at 1064 nm) are lower than that of Bi2Te3/rGO solution due to much higher concentration in the film at the same level of linear transmission. The Bi2Te3/rGO-PVA thin film could be the promising optical limiting materials.

The rational design and controllable preparation of the solid film with strong molecular coupled effect represents a long-standing challenge for developing advanced practical nonlinear optical (NLO) materials. Here, we report a general electrostatic self-assembled strategy toward fabricating tetracarboxylic Nickel(II) naphthalocyanine (NiNcC4) ultrathin film on solid substrate with an ordered molecular arrangement based on the controllable deposition of anionic NiNcC4 naphthalocyanine and cationic polydiallydimethyldiallylammonium chloride (PDDA). The 30-bilayer P/NiNcC4 film shows an ordered conformation of face-to-face molecular arrangement, ultrathin thickness (126.6 nm) and a Raman enhancement phenomenon, and exhibits a high second-order molecular hyperpolarizability γ of 7.0 × 10−27 esu, which is three orders larger than that of NiNcC4 aqueous solution, demonstrating the potential of strongly molecular coupling effects for advanced self-assembled systems.

4-Nitrophenol (4-NP) sensors with high sensitivity and reproducibility are desirable for biosafety and environmental monitoring. Herein, cationic tetra-β-(N,N,N-trimethylaminoethoxy) phthalocyanine cobalt(II)/acid-treated carbon nanotubes multilayer films, marked as (tmaePcCo/CNT)n films (n represents the bilayer number), were successfully constructed on glassy carbon electrode (GCE) by a facile, effective layer by layer (LBL) electrostatic assembly method without the assistant of polyelectrolyte. Because CNTs within the multilayer films are beneficial to collect and transfer charges, and polyelectrolyte-free assembly ensures active sites exposing, the obtained (tmaePcCo/CNT)10/GCE exhibits excellent 4-NP electrocatalytic performance with good reproducibility and acceptable stability, a wide linear calibration range over 3 orders of magnitude of 4-NP concentrations (1 μM–1.8 mM) and a low detection limit of 0.2 μM (S/N = 3), and it can be applied to the quantification analysis of 4-NP under optimum conditions. This work shows that the LBL multilayer films fabricated without polyelectrolyte can provide a valid way to improve the sensitivity and reproducibility of 4-NP sensors.

2,9,16,23-tetra-(6-mercaptohexylthio) phthalocyanine (MPc(THdT), M = Zn, In)-graphene oxide (MPc(THdT)-GO hybrids) and 2,9,16,23-tetra-(6-hydroxyhexyloxy) phthalocyanine (MPc(THdI), M = Zn, In)-graphene oxide (MPc(THdI)-GO hybrids) have been prepared with a covalent functionalization method. A series of characterizations revealed that phthalocyanine is covalently attachment on graphene oxide sheets. The third order nonlinear optical properties were investigated using the Z-scan technique at 532 nm with 4 ns laser pulses. The four kinds of MPc-GO hybrids exhibited much larger nonlinear optical absorption effects than that GO and Pc, respectively. Energy diagrams show that the PET process from Pc molecules to GO nanosheet exists. In the process of PET/ET, thioester bond between GO and MPc(THdT) make process of PET/ET easier, and the nonlinear absorption coefficient β values of MPc(THdT)-GO hybrids are higher than those of MPc(THdI)-GO hybrids.

Room temperature operation, high sensitivity, low detection limit, fast response/recovery, and excellent selectivity are desirable for a wide range of NH3-sensing application. In this report, well-dispersed 2,9,16,23-tetrakis(2,2,3,3-tetrafluoropropoxy) metal(II) phthalocyanine/multi-walled carbon nanotube hybrids (TFPMPc/MWCNT, M = Co, Zn, Cu, Pb, Pd, and Ni) were prepared by using a solution self-assembly method based on π–π stacking interactions. The as-prepared TFPMPc/MWCNT hybrids show a sensitivity response/recovery and excellent selectivity for NH3 at room temperature, especially TFPCoPc/MWCNT sensor. The sensitivity of TFPCoPc/MWCNT to 50 ppm NH3 is about 26%, and the limit of detection is as low as 60 ppb. The enhanced NH3-sensing performance is mainly due to the synergistic effect between TFPMPc and MWCNT, e.g. the stronger adsorption interaction of TFPMPc with NH3, the high electrical conductivity of MWCNT, and the fast charge transfer between TFPMPc and MWCNT. By contrast, the response of various TFPMPc/MWCNT sensors decreases in the order of Co > Zn > Cu > Pb > Pd ≈ Ni, implying that the central metals play a critical role in the sensitivity of NH3. Such results are further evidenced by the binding energies and charge transfers of MPc-NH3 system calculated by the first-principle density functional theory.

A reduced graphene oxide–zinc phthalocyanine (RGO–ZnPc) hybrid material with good dispersibility has been prepared by covalent functionalization method, based on the initial covalent linkage of ZnPc to GO and subsequent in situ reduction of GO moiety to RGO during mild thermal treatment in DMF solvent. The microscopic structure, morphology and photophysical properties of resultant RGO–ZnPc hybrid are characterized. The nonlinear optical (NLO) properties of the RGO–ZnPc hybrid are also investigated using the Z-scan technique at 532 nm with 4 ns laser pulses. The results show that the efficient functionalization and reduction of GO make RGO–ZnPc hybrid possess much larger NLO properties and optical limiting performance than those of individual GO, ZnPc and the GO–ZnPc hybrid. It can be ascribed to a combination of different NLO absorption mechanisms for RGO–ZnPc hybrid, including two-photon absorption originating from the sp3 domains, saturable absorption from the sp2 carbon clusters and excited state absorption from numerous localized sp2 configurations in RGO moiety, reverse saturable absorption arising from ZnPc moiety and the contribution of efficient photo-induced electron transfer or energy transfer process between ZnPc and RGO.

A novel hybrid material composed of reduced graphene oxide (RGO) and 1,8,15,22-tetra-iso-pentyloxyphthalocyanine copper (3-CuPc) derivative was obtained. The resultant RGO/3–CuPc hybrid was characterized by Fourier transform infrared, Ultraviolet-visible, X-ray photoelectron and Raman spectroscopy, transmission electron microscopy and scan electron microscopy. The results indicated that 3-CuPc molecules were successfully anchored on the surface of the RGO sheets by the π–π stacking interaction. The NH3 sensing behaviors of the RGO/3–CuPc hybrids were also investigated and compared with the sensors based on pristine RGO. The results showed that the response of the RGO/3–CuPc hybrid sensor is five times more sensitive than that of pristine RGO, and the recovery time is 10 times faster than that of pristine RGO. The RGO/3–CuPc hybrid sensor exhibited excellent response, reversibility and selectivity, indicating a remarkable accumulation effect as a result of 3-CuPc functionalized graphene. An innovative method for the application of RGO/MPc hybrids in the gas sensing field was provided.

Composite film with alternating layers containing anionic 1,8,15,22-tetrakis (8-quinolineoxy-5-sulfonic acid)-phthalocyanine copper and cationic polydiallydimethylammonium chloride was fabricated by electrostatic self-assembled layer-by-layer (LBL) technique. The microstructure of the film was characterized by a series of techniques. The third-order nonlinear optical properties of the film were measured using 4f coherent imaging system with phase object (NIT-PO) with laser duration of 20 ps at the wavelength of 532 nm. The film exhibited excellent nonlinear absorption and self-focusing effect. The second-order molecular hyperpolarizability γ value of the film reaches as high as 1.54 × 10−29 esu.

Two kinds of novel hybrid materials were prepared by noncovalent functionalized single wall carbon nanotubes (SWCNT) with tetra-α-iso-pentyloxyphthalocyanine copper (CuPcTIP) and tetra-α-(2,2,4-trimethyl-3-pentyloxy) metal phthalocyanines (CuPcTTMP) and characterized by FT-IR spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, transmission electron microscopy and scan electron microscopy. The results revealed that the CuPc derivatives had been successfully anchored on the surface of nanotubes through π–π stacking interaction. The gas sensing behaviors of the SWCNT/CuPcTIP and SWCNT/CuPcTTMP hybrid were investigated with respect to NH3 at room temperature. The response and recovery properties of SWCNT sensor to NH3 are improved due to the synergetic behavior between CuPc and SWCNT. Moreover, the SWCNT/CuPcTIP and SWCNT/CuPcTTMP hybrids to NH3 exhibit excellent reversibility, reproducibility and selectivity. The advantages of combining CuPc derivatives with SWCNT in enhancing the gas sensing properties of the final product were presented, and an innovative method for the application of SWCNT/CuPc hybrids in the gas sensing field was provided.

The carbazole derivatives are suitable for two-photon absorption optical storage and photoluminescence material. Two carbazole derivatives, asymmetrical and symmetrical type molecules containing quinoline rings as electron acceptors and an N-ethylcarbazole group as electron donor, 9-ethyl-3-(2-quinolin)viny-carbazole ( 4 ) and 9-ethyl-3,6-bis(2-(quinolin)vinyl)-carbazole ( 5 ), had been synthesized by the Vilsmeier reaction of formylation and Knoevenagel condensation. The one-photon properties including absorption, fluorescence emission spectra, fluorescence quantum yields and fluorescence decay behaviors were investigated in N,N-dimethylformamide. Meanwhile, these compounds were theoretically surveyed by the density functional theory (DFT) and the time-dependent functional theory (TD-DFT). The two-photon excited fluorescence and two-photon absorption cross-sections were measured for the compounds by 120 fs pulse at 800 nm Ti: sapphire laser operating at 1 kHz repetition rate. The results showed that both of the two compounds 4 and 5 had higher fluorescence quantum yield ( Φ ) of 0.77 and 0.81 comparing with carbazole. Compounds 5 with symmetric π conjugated structure possessed longer fluorescence lifetime ( τ ) of 21.4 ns and larger two-photon absorption cross-sections ( δ TPA ) of 364 × 10 −50 cm 4 s/photon than those of compounds 4 with asymmetric π conjugated structure ( τ = 10.03 ns and δ TPA = 81 × 10 −50 cm 4 s/photon). It was indicated that the one and two-photon optical properties of carbazole derivatives are influenced strongly by the symmetry and length of π conjugated structure.

Two kinds of novel carbon nanotubes hybrids were prepared by noncovalent hybridization of the acidified multi wall carbon nanotubes (MWCNT-COOH) and single wall carbon nanotubes (SWCNT-COOH) with lead 2,9,16,23-tetra-iso-pentyloxyphthalocyanine (PbPc) and characterized by FTIR, absorption spectra and scanning electron microscopy. The results revealed that the PbPc derivatives had been successfully anchored on the surface of nanotubes through π–π stacking. The gas sensing behaviors of the MWCNT-COOH, PbPc/MWCNT-COOH, SWCNT-COOH and PbPc/SWCNT-COOH films were investigated with respect to NH 3 at room temperature. The synergetic behavior between PbPc and CNTs allows an excellent sensitivity to NH 3 . We present the advantages of combining metallophthalocyanine (MPc) with CNTs in enhancing the gas sensing properties of the final product, and pave a new way for the application of MPc/CNTs hybrids in the gas sensing field.

Spin-coating films of copper, lead and nickel 1,8,15,22-tetra-iso-pentyloxyphthalocyanine (Cu, Pb and NiPc(iso-PeO) 4 ) were obtained and characterized by absorption spectra and atomic force microscopy. The gas sensing behaviors of the films were investigated with respect to NH 3 at room temperature. In addition, the effects of film morphology and center metal on gas sensing properties were also discussed. It was found that the MPc(iso-PeO) 4 films exhibited good response, reversibility, stability and faster response and recovery characteristic to NH 3 . The responses were in the following order: CuPc(iso-PeO) 4 , PbPc(iso-PeO) 4 and NiPc(iso-PeO) 4 , and the response and recovery were in the following order: CuPc(iso-PeO) 4 , NiPc(iso-PeO) 4 and PbPc(iso-PeO) 4 .

Spin-coating films of palladium, nickle, and cobalt tetra-( tert -butyl)-5,10,15,20-tetraazaporphyrin complex (Pd, Ni, and CoTAP(t-Bu) 4 ) were obtained and characterized by absorption spectra and atomic force microscopy. The gas sensing behaviors of the films were investigated with respect to NH 3 at room temperature. In addition, the effects of film morphology and center metal on gas sensing properties were also discussed. It was found that the MTAP(t-Bu) 4 complexes exhibited good response, reversibility, stability and ultrafast response and recovery characteristic to NH 3 . The responses were in the following order: PdTAP(t-Bu) 4 , NiTAP(t-Bu) 4 and CoTAP(t-Bu) 4 . The response and recovery times of Pd, Ni, and CoTAP(t-Bu) 4 ) films were

Spin-coating films of tetra-(tert-butyl)-5,10,15,20-tetraazaporphyrin copper (CuTAP(t-Bu)4) and tetra-(tert-butyl) phthalocyanine copper (CuPc(t-Bu)4) was obtained and characterized by absorption spectra and atomic force microscopy. The gas sensing behaviors of the films were investigated with respect to NH3 and NO2 at room temperature. In addition, the interactions between complexes and gas analytes were also discussed. It was found that the devices exhibited better response and slow response–recovery times with increase of interactions between the complexes and analytes related with conjugated ability of complexes. This suggests that the response may imparted by use of strong interactions between the complexes and the analyte of interest at the expense of reversibility.

Tetrafluoropropanol soluble, metal(II) hydrazone complexes derived from alkyl substituted isoxazole and barbituric acid were synthesized and evaluated as suitable optical recording materials for the recordable blu-ray disc system. The behaviour and relationships of the absorption, reflectivity and optical constants (complex refractive indices N = n + ik ) for different metal(II) complexes in spin-coated films were discussed. In addition, the important thermal decomposition data of these metal(II) complexes from simultaneous TG–DSC analyses were presented as well. As an example of the utility of dye-based blu-ray recording media, we used the nickel(II) hydrazone complex thin film as recording layer for static optical recording performance test. Results showed that high reflectivity contrast over 45% and durable information marks (after repeatedly reading 20,000 times) could be achieved under optimum laser writing power and pulse width conditions, indicative of producing a very promising optical recording medium for blu-ray disc-recordable system.

Spin-coated films of 1,4,8,11,15,18,22,25-octa-iso-pentyloxyphthalocyanine lead (PbPc(iso-PeO)8) complex were obtained and characterized by IR spectra, UV–vis absorption spectra. A good linear relationship of the absorbance and solution concentration was detected. Low concentration solution could afford smooth, homogeneous and porous macrostructure film surfaces as indicated by atomic force microscopy. The responses of the films to NO2, NH3, acetone and ethanol vapor were investigated at room temperature. In addition, the response and recovery characteristics, reversibility, selectivity and stability of the film to NO2 were also studied. The results indicated that the PbPc(iso-PeO)8 derivative could be exploited as an NO2 sensor at room temperature.

Multilayer films containing anionic iron phthalocyanine tetrasulfonate (FePcTsNa 4 ) and cationic poly(diallydimethyl ammonium chloride) were prepared using electrostatic self-assembled layer-by-layer technique. The growth of the film was monitored by ultraviolet–visible absorption spectroscopy, and the morphology of the film was characterized by atomic force microscopy. Polarized visible spectra showed that macrocycles of FePcTsNa 4 in the film presented a flat orientation relative to the plane of the solid substrates. The third-order nonlinear optical properties of the film were studied by using Z-scan technique with laser duration of 21 ps at the wavelength of 532 nm. The FePcTsNa 4 /PDDA film exhibited strong self-focusing effect with n 2 value of 4.13 × 10 −15 m 2 /W, which is 4 orders larger than that of FePcTsNa 4 aqueous solution.

An ultrathin composite film with alternating layers containing anionic octacarboxylic copper phthalocyanine [CuPc(COONa)8] and cationic polyethylenimine (PEI) has been prepared by the electrostatic layer-by-layer self-assembly technique. The alternating multilayer assemblies of CuPc(COONa)8/PEI were characterized by UV–Vis spectroscopy, showing the regularly consecutive adsorption process. The film surface was smooth and homogeneous as indicated by atomic force microscopy. The closely packed nanoparticles, with the average diameter of 36 nm and the mean interface roughness of 2.984 nm, can be easily seen on the film surface uniformly. Further structure investigation was carried out by using small angle X-ray diffraction. Third-order nonlinear properties of the film and CuPc(COONa)8 aqueous solution were studied by Z-scan measurements at 532 nm with 8 ns pulses. The ultrathin film depicted strong nonlinear reverse saturable absorption and excellent self-defocusing performance. The second-order molecular hyperpolarizability γ value of the film was 68 times larger than that of solution sample.

Three kinds of rare earth complexes derived from dibenzoylmethane (DBM) ligand were synthesized by reacting free ligand and different rare earth ions(La (3+), Sm3+ and Gd3+). Their contents and structures were postulated based on elemental analysis, LDI-TOF-MS, FT-IR spectra and UV-Vis spectra. Smooth films on K9 glass substrates were prepared using the spin-coating method. Their solubility in organic solvents, absorption and reflection properties of thin film and thermal stability of these complexes were evaluated. These complexes would be a promising recording material for high-density digital versatile disc-recordable (HD-DVD-R) system. (c) 2007 Elsevier B.V. All rights reserved.

The optical limiting properties of the metallic naphthalocyanine with high transmission at visible range were studied by using a double-frequency ns/ps Nd:YAG laser system at 532 nm with pulse width of 8 ns. Influences of Br substitute on excited state absorption are significant. The effective excited state absorption model was used to describe the optical limiting effect.