回顾与展望：酞菁及其应用

本文介绍了酞菁化合物和简史;综述了酞菁化的薄的制备方法。     

酞菁化合物可见光降解水中有机污染物的机理及应用

当前水环境污染已成为全球性普遍关注的重要课题,而利用光催化氧化技术处理水中难降解有机污染物的方法己经引起了国内外水处理专家的广泛关注。自1907年由A.Braun教授和T.C.Tcherniac教授第一次发现酞菁化合物以来,有关利用酞菁化合物对水中污染物进行光催化降解的研究备受瞩目。酞菁化合物由于具有18π电子体系的共轭结构,能吸收可见光区的光,因而显现出独特的光电特性。对酞菁化合物可见光催化降解水中有机污染物研究现状进行了综述,分别介绍了酞菁化合物的典型结构及其特性,并对其催化降解有机污染物反应机理进行阐述,总结了近年来酞菁化合物在降解水中有机污染物方面的应用,从环境可持续发展角度来看,具有十分重要的意义。     

不对称酞菁化合物的合成及研究进展

综述了近年来不对称酞菁化合物的合成进展及不对称酞菁在有机非线性光学、电荷转移、催化剂,分子整流器等领域的研究与应用。     

酸基取代酞菁铜化合物的合成及其光电性研究

合成了一种羧酸基取代的可溶性酞菁铜化合物，并对其光吸收性及导电性进行了研究。结果表明：（１）这种含有羧酸基的酞苯铜化合物在波长５００￣８００ｎｍ有强吸收，较无取代基的酞菁铜化合物吸收波谱范围增宽；（２）该正确性的具有一定的电导性，水解前化合物体电导率为１０＾－７／Ω·ｃｍ，较无取代基的酞菁铜提高了４个数量级。水解后化合物表面电导率为１０＾－２／Ω·ｃｍ；（３）随着电压的增加，羧酸基取代酞菁铜薄膜的     

酞菁及类酞菁的结构与紫外可见光谱研究

介绍了酞菁、亚酞菁和超酞菁的典型结构及其吸收光谱,分别介绍了酞菁和亚酞菁的衍生物、缩合物的结构与最大吸收波长之间的关系以及它们潜在的应用前景,同时分析讨论了几种扩展的酞菁类似物的结构特点和它们吸收性能差的原因.     

基于酞菁光控自组装的超分子三阶非线性光开关材料

酞菁的三阶非线性光学性能不仅取决于其分子结构，而且与酞菁分子在空间的排列密切相关。因此，控制酞菁化合物在空间的排列状态，就有望在超分子的层次控制酞菁的三阶非线性光学性能。我们设计了三类含有光致变色单元修饰的酞菁化合物。利用紫外光和可见交替照射下光致变色单元光异构过程中空间结构和电子结构的改变，实现了对酞菁自组装行为的有效光控。我们用Z-扫描的方法考察了光照前后这些酞菁光控自组装体系三阶非线性光学性能的改变。发现：这些材料不仅开关效应显著，且在“开”和“关”的状态下，都具有大的二阶分子超极化率（〉10^-30esu），在未来光电子和光子技术领域具有潜在的应用价值。     

金属酞菁衍生物的合成及三阶非线性光学性能

合成了四硝基酞菁钴、四氨基酞菁钴以及二硝基二氨基酞菁钴等金属酞菁衍生物。根据IR、UV—Vis和元素分析．确定了它们的结构。使用四波混频技术测量了它们在DMF溶液中的三阶非线性光学系数Z^[3]值,发现金属离子和酞菁环上的取代基对酞菁化合物的三阶非线性光学性能都有较大的影响,本文初步讨论了这些因素对三阶非线性光学性质的影响机理。     

含不齐羧基钴酞菁的制备及其分子聚集效应比较

以偏苯三甲酸酐、邻苯二甲酸酐、尿素等为原料,采用固相法合成了带不对称羧基的金属钴酞菁(Co-nCPc),同时比较性地合成了不带任何取代基的金属钴酞菁(CoPc)以及四羧基钴酞菁(Co-TCPc)。对这3类化合物进行了元素分析、UV和IR表征,UV和IR分析确认了Co-nCPc的酞菁结构,从元素分析结果推断Co-nCPc化合物可能是由一羧基、二羧基、三羧基钴酞菁化合物混合组成。将Co-TCPc和Co-nCPc与蚕丝素蛋白(SF)共混反应得到负载钴酞菁化合物Co-TCPc-SF和Co-nCPc-SF,比较了CoPc、Co-TCPc、Co-nCPc、Co-TCPc-SF和Co-nCPc-SF对氨气和硫化氢的催化消臭效果。结果显示,Co-TCPc的消臭效能强于Co-nCPc,但负载到SF上后,Co-nCPc-SF的消臭效能变得强于Co-TCPc-SF,推测Co-nCPc具有较小的聚集态势。     

两种四硝基酞菁的合成及光谱性质研究

用4-硝基邻苯二甲酰亚胺、3-硝基邻苯二甲酸酐分别和4种金属盐、尿素、钼酸铵在熔融状态下合成2,9,16,23-四-硝基金属酞菁、1,8,15,22-四-硝基金属酞菁,时产物进行了IR、UV-vis光谱测定和表征,并分别对比不同金属酞菁的谱学性质.实验结果表明,在紫外吸收光谱中,4种金属对于两类酞菁化合物最大吸收波长的影响是Zn＞Cu＞Ni＞Co.     

REVERSE OPTICAL CHANGE AND RECORDING CHARACTERISTICS OF LANGMUIR-BLODGETT FILMS OF PHTHALOCYANINE COMPOUNDS

报导了酞菁化合物的吸收光谱随中心金属离子的有机基团的替代而产生的变化，以及酞菁铜（ＴＮＰｃＣｕ）和酞菁锌（ＴｎＰＰｃＺｎ）的单分子薄膜的吸收光谱随温度的变化。发现酞菁铜薄膜在７４０ｎｍ波长的光吸收的滞后回旋现象以及酞菁锌的可逆光吸收变化。报导了利用上述现象的可擦重写的光存储特性。     

Phthalocyanines

Progress in recent investigations of phthalocyanines (Pcs) and their analogues has been reviewed with emphasis on the work carried out in 1998. In particular, the synthesis and identification of low symmetrical Pc analogues or dendritic and optically active Pcs, and the characterization of Pcs by newly developed analytical and spectroscopic methods, are described.     

1,4,8,11,15,18,22,25-octasubstituted phthalocyanines: the contrasting effects of alkyl and alkoxy substituents on molecular self-assembly

The introduction of eight alkoxy or eight alkyl substituents onto the phthalocyanine (Pc) nucleus at the non-peripheral (1,4,8,11,15,18,22,25) positions produces derivatives which are soluble in a variety of organic solvents. However, other physico-chemical properties of the two series differ. Octa-alkyl derivatives, R₈ Pcs, pack as more ordered molecular assemblies in the solid state and show thermotropic liquid crystal behaviour with transition temperatures dependent upon substituent chain length and the central metal atom. In contrast, octa-alkoxy materials, (RO)₈ Pcs, melt directly into the isotropic liquid. The latter can be deposited as Langmuir-Blodgett films whereas the former cannot. Experiments with examples of the two series in which one or two of the chains are functionalized at the terminal positions with a hydrophilic moiety show that these amphiphilic analogues deposit well by the Langmuir-Blodgett method. A number of the films show a high degree of molecular ordering, as judged by X-ray reflectivity methods, transmission infrared, RAIRS and polarized optical spectroscopy. Results indicate that the type of ordering is controlled by the type of substituent and the length of the chain.     

1,4,8,11,15,18,22,25-octasubstituted phthalocyanines: the contrasting effects of alkyl and alkoxy substituents on molecular self-assembly

The introduction of eight alkoxy or eight alkyl substituents onto the phthalocyanine (Pc) nucleus at the non-peripheral (1,4,8,11,15,18,22,25) positions produces derivatives which are soluble in a variety of organic solvents. However, other physico-chemical properties of the two series differ. Octa-alkyl derivatives, R₈ Pcs, pack as more ordered molecular assemblies in the solid state and show thermotropic liquid crystal behaviour with transition temperatures dependent upon substituent chain length and the central metal atom. In contrast, octa-alkoxy materials, (RO)₈ Pcs, melt directly into the isotropic liquid. The latter can be deposited as Langmuir-Blodgett films whereas the former cannot. Experiments with examples of the two series in which one or two of the chains are functionalized at the terminal positions with a hydrophilic moiety show that these amphiphilic analogues deposit well by the Langmuir-Blodgett method. A number of the films show a high degree of molecular ordering, as judged by X-ray reflectivity methods, transmission infrared, RAIRS and polarized optical spectroscopy. Results indicate that the type of ordering is controlled by the type of substituent and the length of the chain.     

The effect of aggregation on the nonlinear optical absorption performance of indium and gallium phthalocyanines in a solution and co-polymer host

The nonlinear optical properties (NLO) of Pcs can be modified by substituting different metal atoms into the ring or altering peripheral and axial functionalities. In this study, nonlinear optical absorption properties of tetra-substituted gallium and indium phthalocyanine complexes both in solution and polymeric film have been investigated by open aperture Z-scan measurements with nanosecond pulses at 532 nm. All investigated compounds exhibited reverse saturable absorption for both solution and film experiments. The investigated compounds in the solution showed better nonlinear optical absorption properties than polymeric films. The observed nonlinear optical absorption differences depending on the aggregation are discussed using the ultrafast dynamics and decay processes of excited states found from femtosecond pump-probe spectroscopy with white light continuum experiments.     

Electrical and optical properties of phthalocyanine films

Thin films of various phthalocyanines (Pcs) were sublimed onto quartz glass in ultrahigh vacuum. The electrical and optical properties were studied without breaking the ultrahigh vacuum. The dyes were purified by repeated sublimation in vacuum.The conductivity varied with pretreatment (modification) and temperature. Exposure to oxygen, iodine and bromine increased the p-type conductivity by orders of magnitude and lithium doping caused n-type conductivity. Heavy exposure to halogens caused not only broadening of the optical absorption band but also bleaching. Annealing in vacuum removed the electrical and optical effects of doping nearly completely.Field effect studies were used to identify p- and n-type conductivity, to determine the drift mobility and to estimate the trap densities. The field effect and the photoconductivity of p- and n-type films increased by several orders of magnitude with the dark conductivity, i.e. with doping. This correlation is attributed either to traps with a continuous distribution in energy or to trapping by at least two discrete defect levels crossing the Fermi level within the surface-induced accumulation layer. Possible consequences for the sensitivity of semiconductor gas sensors are discussed.     

Effects of oxidizing gases on semiconductivity and thermal stability of phthalocyanine thin films

The effects of oxidizing gases (O₂ and NO₂) on the p-type semiconductivity of the phthalocyanines H₂Pc, PbPc, ZnPc, CuPc, AlPcCl, AlPc-O-AlPc and (AlPc) _n films treated in nitrogen at 350 ° C have been examined. The conductance increased in the presence of oxidizing gases. Reversible effects of oxidizing gases on the conductance were observed for PbPc, CuPc and ZnPc, all of which are thermally and/or chemically less stable than the other Pcs. For the latter, the conductance in nitrogen increased permanently after exposure to NO₂. The reversibility of the former may be related to the thermal and chemical stability of neutral and/or oxidized phthalocyanines. The conductivity is described byG =G ₀ exp (E/kT) The activation energy,E, decreased in the presence of oxidizing gases. The pre-exponential factor,G ₀, was lowered by the introduction of NO₂ especially for PbPc, CuPc and ZnPc. It seems that the adsorption of NO₂ is limited to the surface of fine crystals and the increase in the conductance caused by exposure to NO₂ is strongly influenced by the crystallinity of phthalocyanine.     

Indium(III) and Gallium(III) phthalocyanines-based nanohybrid materials for optical limiting

Linear and nonlinear optical properties of a phthalocyanine (Pc)-based nanohybrid material PCIGS [Cu₂(tBu₄PcGa)(tBu₄PcIn)S₂TPP₂] are described. The overall aggregation of phthalocyanines in poly(methylmethacrylate) (PMMA) films was evident, which is indicated by the broadening of linear spectra in the Q-band region and the shift of wavelength. Upon excitation with nanosecond laser pulse at 355 nm, the transient absorption band appeared at about 500 nm is attributed to the triplet–triplet absorption of the Pcs. For PCIGS and its starting materials tBu₄PcGaCl and tBu₄PcInCl, all Z-scans exhibit a decrease in transmittance about the focus typical of an induced positive nonlinear absorption of incident light. The absorption mechanism is due to population of excited states through a multi-step nonlinear absorption. When these Pc compounds were embedded into a commercially available polymer PMMA, all the Pc/PMMA composites display much larger nonlinear absorption coefficient and lower saturable fluence for optical limiting when compared to the same Pc molecules in solution. However, in contrast to tBu₄PcGaCl and tBu₄PcInCl, PCIGS displayed decreased optical limiting response, possibly due to competing electron accepting processes in the In and Ga metals, and the highly ordered structure of the PCIGS complex itself.     

Nonlinear optical behavior of alkyne terminated phthalocyanines in solution and when embedded in polysulfone as thin films: Effects of aggregation

We report here for the first time, on the comparative studies of the photophysical and optical limiting behavior of our two novel phthalocyanines namely 2(3), 9(10), 16(17), 23(24)-tetrakis-(4-(5-methylhex-1-yn-3-yloxy)) phthalocyanines 2, and 2(3), 9(10), 16(17), 23(24)-tetrakis-(4-(5-methylhex-1-yn-3-yloxy)) phthalocyaninato zinc (II) (3) in solution and thin films. Nonlinear optical (NLO) properties of the samples in solution and contained in polysulfone (PSU) thin films were evaluated using Z-scan technique at 532 nm and 10 ns pulsed duration. Effects of aggregation and disaggregation on the NLO performance of metal-free phthalocyanine are reported in detail. Our findings showed that the prepared Pcs show larger nonlinear absorption coefficient and lower limiting thresholds when embedded in polysulfone films compared to in solutions. The values of nonlinear susceptibility and hyperpolarizability recorded for 3-PSU in this work are respectively, ∼2.09 × 10⁻⁸ esu and ∼1.02 × 10⁻²⁶ esu. These values are among the largest values reported for phthalocyanines and other macrocycles doped on polymer matrices.     

Biomaterials and magnetism

Magnetism plays an important role in different applications of health care. Magnetite (Fe₃O₄) is biocompatible and therefore is one of the most extensively used biomaterials for different applications ranging from cell separation and drug delivery to hyperthermia. Other than this, a large number of magnetic materials in bulk as well as in the form of nano particles have been exploited for a variety of medical applications. In this review, we summarize the salient features of clinical applications, where magnetic biomaterials are used. Magnetic intracellular hyperthermia for cancer therapy is discussed in detail.