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Design and engineering of highly efficient light-harvesting nanomaterial systems to emulate natural photosynthesis for maximizing energy conversion have stimulated extensive efforts. Here we present a new class of photoactive semiconductor nanocrystals that exhibit high-efficiency energy transfer for enhanced photocatalytic hydrogen production under visible light. These nanocrystals are formed through noncovalent self-assembly of In(III) meso-tetraphenylporphine chloride (InTPP) during microemulsion assisted nucleation and growth process. Through kinetic control, a series of uniform nanorods with controlled aspect ratio and high crystallinity have been fabricated. Self-assembly of InTPP porphyrins results in extensive optical coupling and broader coverage of the visible spectrum for efficient light harvesting. As a result, these nanocrystals display excellent photocatalytic hydrogen production and photostability under the visible light in comparison with the commercial InTPP porphyrin powders.

We present the fabrication of a novel Starfruit‐shaped metal‐organic framework (SMOF) composed of zirconium and Tetra(4‐carboxyphenyl)porphine linkers. The SMOF exhibits a unique morphology with edge‐sharing two‐dimensional (2D) nanosheet petals. Our investigation unravels a captivating transformation process, wherein three‐dimensional (3D) shuttle‐shaped MOFs form initially and subsequently evolve into 2D nanosheet‐based SMOF structures. The distinct morphology of SMOF showcases superior catalytic activity in detoxifying G‐type nerve agent and blister agent simulants, surpassing that of its 3D counterparts. This discovery of the 3D‐to‐2D transition growth pathway unlocks exciting opportunities for exploring novel strategies in advanced MOF nanostructure development, not only for catalysis but also for various other applications. [ABSTRACT FROM AUTHOR]

Pollutant degradation has been a very important topic in environmental research. The present paper presents an approach to degrade atrazine, an environmentally harmful herbicide that has been widely used in the agriculture industry. Ti/TiO2 nanotube electrodes modified by porphyrins were prepared for photolysis, photocatalysis, and photoelectrocatalysis (PEC) applications. Manganese- and free base porphyrin were studied, and it was possible to verify the kinetic model more suitable for each system. Unfortunately, Mn-porphyrins had an inhibitory effect on the ATZ degradation activity by Ti/TiO2 nanotube electrodes. Although the Ti/TiO2-free base porphyrin under the PEC experiment (using surface water from a Brazilian river) did not lead to the best degradation system, we could verify the formed products, which have been not described for other porphyrin-mediated atrazine degradation, are equal or more toxic than the original atrazine. We highlight the importance of verifying the products formed in the degradation systems and determining their toxicities. [ABSTRACT FROM AUTHOR]

One striking feature of enzyme is its controllable ability to trap substrates via synergistic or cooperative binding in the enzymatic pocket, which renders the shape‐selectivity of product by the confined spatial environment. The success of shape‐selective catalysis relies on the ability of enzyme to tune the thermodynamics and kinetics for chemical reactions. In emulation of enzyme's ability, we showcase herein a targeting strategy with the substrate being anchored on the internal pore wall of metal‐organic frameworks (MOFs), taking full advantage of the sterically kinetic control to achieve shape‐selectivity for the reactions. For this purpose, a series of binding site‐accessible metal metalloporphyrin‐frameworks (MMPFs) have been investigated to shed light on the nature of enzyme‐mimic catalysis. They exhibit a different density of binding sites that are well arranged into the nanospace with corresponding distances of opposite binding sites. Such a structural specificity results in a facile switch in selectivity from an exclusive formation of the thermodynamically stable product to the kinetic product. Thus, the proposed targeting strategy, based on the combination of porous materials and binding events, paves a new way to develop highly efficient heterogeneous catalysts for shifting selectivity. [ABSTRACT FROM AUTHOR]

Hydrogen molecule (H2) exhibits broad-spectrum but microenvironment-dependent biomedical effects in varied oxidation stress-related diseases, but its molecular mechanism is unclear and its targeting molecule is unknown so far. Herein, we originally reveal that Fe-porphyrin is a H2-targeted molecule. We have demonstrated that the oxidized Fe-porphyrin in both free and protein-confining states can self-catalyze the hydrogenation/reduction by reacting with H2 to catalytically scavenge ·OH, and can also catalytically hydrogenate to reduce CO2 into CO in the hypoxic microenvironment of in vitro simulation and in vivo tumor, confirming that Fe-porphyrin is a redox-related biosensor of H2 and H2 is an upstream signaling molecule of CO. These discoveries are favorable for deep understanding and exploration of profound biomedical effects of H2, and helpful for development of innovative drugs and hydrogen energy/agricultural materials. [ABSTRACT FROM AUTHOR]

Herein, a series of metallo-porphyrins, corroles and phthalocyanines were applied as the key precursors to confirm the influence of macrocyclic cores on the preparation of single- and dual-metal nitrogen-doped carbon (M-N-C) catalysts, and the control the M-N-C catalyst preparation towards accelerating electrocatalyzed hydrogen evolutions could be rationally modulated. Due to the synergetic effect, the dual-metal Co 0.97 Cu 0.03 TPP@rGO-900 M-N-C catalyst has the best performance on the electrochemically catalyzed hydrogen evolution with onset potentials as −166 mV and Tafel 117 mV·dec−1. More importantly, these M-N-C catalysts could also be used in a wide range of pH values, such as PBS and KOH medias. • The influences of macrocyclic precursors on the preparation and catalysis of M-N-C catalysts were studied. • Due to the synergetic effect, the dual-metal Co 0.97 Cu 0.03 catalyst has the better HER performance. • These catalysts can be effectively used in a wide range of pH values. [ABSTRACT FROM AUTHOR]

The review presents recent examples of heterogenic catalysts based on porphyrins and phthalocyanines loaded on mesoporous materials, such as MCM-41, SBA-15, MCM-48, SBA-16 or Al-MCM-41. Heterogenic approach to catalysis eases recovery, reuse and prevent macrocycle aggregation. In this application, mesoporous silica is a promising candidate for anchoring macrocycle and obtaining a new catalyst. Introduction of porphyrin or phthalocyanine into the mesoporous material may be performed through adsorption of the macrocycle, or by its in situ formation—by reaction of substrates introduced to the pores of the catalytic material. Catalytic reactions studied are oxidation processes, focused on alkane, alkene or arene as substrates. The products obtained are usually epoxides, alcohols, ketones, aldehydes or acids. The greatest interest lies in oxidation of cyclohexane and cyclohexene, as a source of adypic acid and derivatives. Some of the reactions may be viewed as biomimetic processes, resembling processes that occur in vivo and are catalyzed by cytochrome P450 enzyme family. [ABSTRACT FROM AUTHOR]

This review covers recent progress in the field of nitrosyl pincer and porphyrinate complexes, and how their reactivity depends on the redox state of the NO ligand. Synthetic methods, and the most significant structural information, spectroelectrochemical studies, and different reactivities of nitrosyl pincer complexes are presented. These include selective activation and functionalization of carbon‐halogen bonds, catalysis for a variety of specific organic reactions, mediation of NO disproportionation and reversible coordination of solvents and weakly‐coordinating anions. Regarding the porphyrinate complexes, the focus is on biorelevant nitroxyl (NO−/HNO) complexes, discussing pioneering studies along with preparation and common characterization methods. Their relative stability in different conditions is compared, and possible decomposition mechanisms are discussed in terms of their ability to act as biomimetic models for enzymatic systems. [ABSTRACT FROM AUTHOR]

El rojo de alizarina es un colorante de antraquinona soluble en agua que se usa ampliamente en la industria textil como agente de tinción y se considera uno de los contaminantes más recalcitrantes y duraderos. La reacción de Fenton puede usarse para destruir una amplia variedad de compuestos orgánicos: un ion ferroso reacciona con el peróxido de hidrógeno (H2O2) para formar un radical hidroxilo (HO•) que es un poderoso agente oxidante. La velocidad de esta reacción podría aumentarse cuando se expone a la luz UV-Vis, este método se conoce como proceso de Foto-Fenton y constituye una alternativa atractiva a los procesos de oxidación avanzada. En este trabajo se estudió la decoloración fotocatalítica del colorante rojo de alizarina mediante un proceso Foto-Fenton heterogéneo inducido por luz visible; para tal fin, se utilizaron películas delgadas de tetra(4-carboxifenil) porfirina de hierro (III) adsorbidas sobre dióxido de silicio. La caracterización del catalizador fue realizada por UV-Vis, reflectancia difusa e IR-FT. Los ensayos fueron realizados a tres (3) valores de pH 1.0, 3.0 y 5.0; finalmente, se utilizó el modelo cinético descrito por Langmuir-Hinshelwood para obtener los parámetros cinéticos del proceso de fotodecoloración. Los resultados mostraron que la mayor decoloración del rojo de alizarina se presentó a un pH de 1.0; además, el modelo de pseudo-primer orden aplicado permitió obtener la constante de velocidad (k) del proceso de decoloración encontrando que el mayor valor de k fue 1.1x10-2 min-1. Los radicales hidroxilo se detectaron por atrapamiento químico a través de fluorescencia indirecta del ácido 2-hidroxitereftálico. Los procesos de foto-Fenton basados en sistemas de catálisis heterogénea resuelven parte de estos problemas ambientales, proporcionando una fácil separación y recuperación del catalizador de las aguas residuales tratadas, en el que no es corrosivo y, además, es ecológico.

The iron metalation of the known free‐base porphyrins H2P2 and H2P3, obtained by structural modification of the well‐known TPPF20 (H2P1) with galactose dendritic units, gave the corresponding iron(III) porphyrin complex FeP2 and the solid hybrid material FeP3S. Their synthesis, characterization and catalytic efficacy toward the oxidation of the organic substrates (Z)‐cyclooctene, cyclohexane and heptane, are reported. In this work, the possibility to modulate selectivity and chemical efficiency of the catalytic system by using simple and more sophisticated metalloporphyrins is demonstrated. Furthermore, the presence of the galactose dendrimer units at the meso‐porphyrin ring positions can tune the oxidation at the terminal positions in linear alkanes. In addition, the FeP3S material was easily recovered and reused at least 3 times for the cyclooctene oxidation. The catalytic performance of material FeP3S, associated with their possibility of reuse, makes this material a promising catalyst. [ABSTRACT FROM AUTHOR]

The catalytic reduction of O2 by a manganese(III) porphyrin immobilized in a nanostructured semiconductive transparent TiO2 electrode is here investigated by UV‐Vis spectroelectrochemistry in an aqueous buffered medium. Analysis of the operando spectroelectrochemical data, collected for both the immobilized catalyst and the TiO2 matrix, demonstrates the coexistence of two faradaic electrochemical processes, namely (i) irreversible interfacial electron transfer from TiO2 to the immobilized porphyrin triggering the catalytic reduction of O2, and (ii) reversible proton‐coupled electrochemical reduction of TiO2 leading to the accumulation of electrons in the TiO2 bulk. The competition between these two processes is modulated by the local concentration of O2, which itself varies with the rate of the catalysis. Indeed, when O2 is locally strongly depleted by catalysis, the process switches from catalysis to charge storage, like a battery. As a result, the electrons stored in TiO2 were observed to pursue the catalysis even after the electrode polarization was switched‐off (i. e., under open circuit). This is an overlooked phenomenon that we believe is important to consider in applications relying on metal oxide‐based photoelectrodes operating in aqueous media. [ABSTRACT FROM AUTHOR]

• µ-nitrido diiron phthalocyanine and porphyrin complexes were prepared. • The catalytic activities of µ-nitrido diiron phthalocyanine and porphyrin complexes were tested in oxidation of several alcohols. • Mechanistic and computational studies were made. µ-Nitrido diiron porphyrinoids complexes, based either on porphyrins or phthalocyanines, are known as excellent oxidation catalysts. While many works have investigated the effect of the substitution pattern on their catalytic activity, a comparison of the effect of the macrocycle remains yet to be conducted. For this purpose, tert -butyl substituted (FePc) 2 N and (FePor) 2 N have been selected as they have both been thoroughly but separately used for oxidation catalysis. Herein, their catalytic activities were tested on model oxidation reactions of various alcohols. The phthalocyanine-based complex (FePc) 2 N proved to be a far more efficient catalyst than its porphyrin counterpart (FePor) 2 N. Computational studies rationalized these experimental observations by showing that the intermediates formed by (FePc) 2 N are thermodynamically more stable than those formed by (FePor) 2 N. [Display omitted] [ABSTRACT FROM AUTHOR]

Macrocyclic compounds have been studied extensively as the host molecules in supramolecular chemistry. Their structural characteristics make macrocycles desirable in the field of molecular recognition, which is the key to high catalytic efficiencies of natural enzymes. Therefore, macrocycles are ideal building blocks for the design of bioinspired catalysts. This mini review highlights recent advances ranging from single-molecule to metal-organic framework materials, exhibiting multilevel macrocycle catalysts with unique catalytic centers and substrate-binding affinities.

The cycloaddition of CO2 to N‐alkyl aziridines was efficiently promoted by the convenient TPPH2/TBACl binary catalytic system. The metal‐free procedure was effective for the synthesis of differently substituted N‐alkyl oxazolidin‐2‐ones in yields up to 100 % and excellent regioselectivities (up to 99 %). The mechanism of the reaction was proposed based on a DFT study which indicated the formation of an adduct between TPPH2 and TBACl as the effective catalytic active species. [ABSTRACT FROM AUTHOR]

The synthesis, characterization and CO2 uptake tendency of a new porous organic polymer (POP) based on porphyrin-pyromellitic dianhyderide is enclosed. The reported porphyrin POP was achieved by exploiting the condensation reaction between tetraaminophenylporphyrin (TAPP) with benzenetetracarboxylic (pyromellitic) diahhydride in dry dimethylforamide (DMF). The structure of the resulting polymer was confirmed by FT-IR as well as solid state 13C cross-polarization magic angle spinning (CP/MAS) NMR studies. In addition, the post-synthetic metallation of the free-base porphyrin macrocycles of the resulting POP with either Zn or Mn metals afforded the metallo-porphyrin POP analogues in excellent yields. The morphology of the reported porphyrin POPs were investigated by scanning electron microscopy (SEM) which demonstrated the porosity of the resulting POPs. Furthermore, CO2 adsorption capabilities of the synthesized POPs were evaluated and Brunauer-Emmett-Teller (BET) surface area was found to be 542, 597 and 828 m2/g for free-base, Zn- and MnIII-POP, respectively. Finally, MnIII-POP was found to be an effective catalyst for the selective epoxidation of styrene to the corresponding epoxide. [ABSTRACT FROM AUTHOR]

The review presents recent examples of heterogenic catalysts based on porphyrins and phthalocyanines loaded on mesoporous materials, such as MCM-41, SBA-15, MCM-48, SBA-16 or Al-MCM-41. Heterogenic approach to catalysis eases recovery, reuse and prevent macrocycle aggregation. In this application, mesoporous silica is a promising candidate for anchoring macrocycle and obtaining a new catalyst. Introduction of porphyrin or phthalocyanine into the mesoporous material may be performed through adsorption of the macrocycle, or by its in situ formation—by reaction of substrates introduced to the pores of the catalytic material. Catalytic reactions studied are oxidation processes, focused on alkane, alkene or arene as substrates. The products obtained are usually epoxides, alcohols, ketones, aldehydes or acids. The greatest interest lies in oxidation of cyclohexane and cyclohexene, as a source of adypic acid and derivatives. Some of the reactions may be viewed as biomimetic processes, resembling processes that occur in vivo and are catalyzed by cytochrome P450 enzyme family.

Although heterogeneous catalysts can be seperated from reaction media easily, catalyst efficiency is often decreased compared to homogeneous counterparts. In this study, catalytic oxidation of thymol and carvacrol were investigated using micron and nano‐sized PCN‐222(Fe) as heterogeneous catalysts and water soluble Fe‐porphyrin complex (FePTC) as homogeneous catalyst in the presence of peroxymonosulfate (PMS). Fe‐porphyrin complexes is well‐known catalyst for oxidation reactions. PCN‐222(Fe), a Zr‐based mesoporous MOFs utilizing porphyrin as organic linker, exhibits similar catalytic performance compared to FePTC for the first use. However, higher conversion values were achieved in PCN‐222(Fe) for the second cycles compared to the homogeneous systems highlighting the importance of heterogeneous MOF system. Thymoquinone (TQ) selectivities of the carvacrol oxidation are 5 and 8 times higher than homogeneous system in the second cycle for nano‐ and micro‐PCN222(Fe), respectively. Importantly, PCN‐222(Fe) can be used for at least 3 cycles with the reduced PMS:catalyst mole ratio. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesized MnTP@ZnAdCOF was characterized and its use as a catalyst in ODS was studied. • Desulphurizing ability of MnTP@ZnAdCOF was above than 98% for thiobenzoic acid. • RP-HPLC chromatograms for thiobenzoic acid represented the catalytic effect of MnTP@ZnAdCOF. • Effect of different temperatures and H 2 O 2 /TB molar ratio on ODS process was observed. • Kinetic study was done in order to determine the percentage desulfurization for TB. Sulfur compounds cause substantial environmental pollution problems, and their immediate removal is urgently needed to keep the environment clean. Fuel desulfurization is necessary due to the severe impacts of sulfur on humans, wildlife, and crops when emitted into the atmosphere during fuel combustion. Fuels with high sulfur contents used in automobiles and factories are the primary source of atmospheric sulfur. A new covalent organic framework (COF) MnTP@ZnAdCOF [(N(C 4 H 9) 4 ] 12 [{NHC(CH 2 O) 3 } 4 (CO) 4 C 44 H 24 N 4 Mn(OCOCH 3)][ZnMo 6 O 18 ] 4 is synthesized and characterized thoroughly using FT-IR, UV/visible, 1HNMR, TGA, PXRD, SEM-EDX, cyclic voltammetry and fluorescence spectroscopy. Herein, an environmentally safe and cost-effective approach for the ODS of thiobenzoic acid is reported using H 2 O 2 as an oxidant and MnTP@ZnAdCOF as a heterogenous catalyst under mild reaction conditions. Desulphurization results of the catalyst are confirmed by the RP-HPLC technique using acetonitrile and water in a 50:50 M ratio as a mobile phase. Active intermediates [(Por)(OAc)Mn-OOH]−, [(Por)(OAc)MnIV O] and Mo(O 2) are formed due to oxidation of Mn and Mo metal in the presence of H 2 O 2 considered responsible for the excellent catalytic efficiency of MnTP@ZnAdCOF catalyst up to 98% desulphurization efficiency was observed. Incredible catalytic conversion of dibenzothiophene, thiobenzoic acid and the mixture of different Sulphur containing compounds to sulfoxide is observed at 25 ℃ temperature. The H 2 O 2 /S molar ratio of 5:1 is an outstanding achievement that can be utilized for the oxidation of sulfur compounds present in diesel to reduce the sulfur contents of fuel. [ABSTRACT FROM AUTHOR]

Through metal-free protocol, hypercrosslinked porous polyporphyrin with permanent porosity was obatined via the Friedel–Crafts alkylation of tetracarbazolylporphyrin using formaldehyde dimethyl acetal as an external cross-linker. Its chemical structure and porosity was well characterized and confirmed. The BET specific surface area value of HCP-TCPP is 1050 m2 g−1 and related dominant pore size is centered at 0.63 nm. The adsorption amount of methanol by HCP-TCPP is high up to 800 mg g−1 (about 25.0 mmol g−1) at its saturated vapor pressure, which is higher than that of toluene (600 mg g−1, 6.5 mmol g−1). Further study indicates that polymer HCP-TCPP, possessing the high BET specific surface area and total pore volume, exhibits good hydrogen uptake of 3.44 wt % (77 K) and high carbon dioxide uptake of 41.1 wt % (298 K) at 18.0 bar. Besides, the obtained porous polymer can also be used as an effective heterogeneous catalyst for the Knoevenagel condensation between various aldehydes and malononitrile.

5-Aminolevulinate (ALA) synthase (ALAS), a homodimeric pyridoxal-5′-phosphate (PLP)-dependent enzyme, catalyzes the first step of heme biosynthesis in metazoa, fungi and α-proteobacteria. In this review, we focus on the advances made in unraveling the mechanism of the ALAS-catalyzed reaction during the past decade. The interplay between the PLP cofactor and the protein moiety determines and modulates the multi-intermediate reaction cycle of ALAS, which involves the decarboxylative condensation of two substrates, glycine and succinyl-CoA. Substrate binding and catalysis are rapid, and product (ALA) release dominates the overall ALAS kinetic mechanism. Interconversion between a catalytically incompetent, open conformation and a catalytically competent, closed conformation is linked to ALAS catalysis. Reversion to the open conformation, coincident with ALA dissociation, defines the slowest step of the reaction cycle. These findings were further substantiated by introducing seven mutations in the16-amino acid loop that gates the active site, yielding an ALAS variant with a greatly increased rate of catalytic turnover and heightened specificity constants for both substrates. Recently, molecular dynamics (MD) simulation analysis of various dimeric ALAS forms revealed that the seven active site loop mutations caused the proteins to adopt different conformations. In particular, the emergence of a β-strand in the mutated loop, which interacted with two preexisting β-strands to form an anti-parallel three-stranded β-sheet, conferred the murine heptavariant with a more stable open conformation and prompted faster product release than wild-type mALAS2. Moreover, the dynamics of the mALAS2 active site loop anti-correlated with that of the 35 amino acid C-terminal sequence. This led us to propose that this C-terminal extension, which is absent in prokaryotic ALASs, finely tunes mammalian ALAS activity. Based on the above results, we extend our previous proposal to include that discovery of a ligand inducing the mammalian C-terminal extension to fold offers a good prospect for the development of a new drug for X-linked protoporphyria and/or other porphyrias associated with enhanced ALAS activity and/or porphyrin accumulation. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are one of the most rapidly developed porous materials and have exhibited high surface area and uniform pore size distributions as promising materials for the fields of gas adsorption, catalysis, chemical sensing, photoelectricity devices and energy storage. In this review, we summarized the recent advances on synthesis, structure, and application of porphyrin-containing COFs. [ABSTRACT FROM AUTHOR]

Porphyrins and their derivatives have attracted great attention due to their unique properties and diverse functionalities which contribute to their wide applications such as catalysis, solar cells, biomedicine and environmental science. It is interesting to note that porphyrin-containing polymers have recently aroused great interest due to the simultaneous presence of both porphyrinic and polymeric characteristics, especially for porphyrin-containing polymers linked by covalent bonds giving well-defined macromolecular architectures, unique self-assembly morphologies and promising applications. Herein, we summarize the different synthetic strategies and self-assembly protocols adopted in recent years to explore various applications of porphyrin-based functional polymers followed by a brief discussion on the challenges and outlooks for future research. With the discovery of advanced polymerization techniques such as living/controlled radical polymerization and click chemistry, the synthesis of porphyrin-containing functional polymers with well-defined architectures has been greatly developed. Porphyrin molecules tend to form the aggregates based on the self-assembly driving force of π-π stacking. Much attention has been paid to the self-assembly behavior of porphyrin-containing functional polymers, and various nanostructures have been constructed including nano-sized or micron-sized spheres, vesicles, belts, wires, rings, tubes, and rods. Porphyrin-containing functional polymers, with special photochemical and photophysical properties, present significant applications in photovoltaics, catalysis, biological and biomedicine fields. Particularly, the porphyrin-based photosensitizers for photodynamic therapy, porphyrin-conjugated polymers for solar cell devices, porphyrin-based polymeric nanocomposites in catalysis and chemical adsorption and separation have been widely studied. We hope this review on porphyrin-based functional polymers will be beneficial to researchers and newcomers in related fields. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Structural and electronic properties of homoleptic and heteroleptic binuclear complexes are considered. • Homometallic M O M and heterometallic M O M′ complexes involving Fe, Mn, Ru, Cr, Mo, Re, Al, Si, P, B. • Covalently linked and non-covalently assembled µ-oxo dimeric structures. • Catalytic and photocatalytic applications. • Application of µ-oxo binuclear complexes in optoelectronic and medical applications. Abstract This review covers recent advances in the preparation, characterization and application of µ-oxo dimeric complexes with different metals and non-metal and macrocyclic ligands achieved during last ten years. Binuclear iron, manganese, ruthenium, chromium, molybdenum, rhenium, aluminium, silicon, phosphorus and boron oxygen-bridged complexes supported by phthalocyanine, porphyrin, porphyrazine, corrole, tetrabenzotriazacorrole, subphthalocyanine and subporphyrin ligands have been prepared and characterized demonstrating a great versatility of µ-oxo binuclear macrocyclic platform which can accommodate a myriad of homoleptic and heteroleptic combinations with the same or different metal sites. They exhibit interesting structural and electronic properties allowing their increasing use in catalysis, optoelectronic, medical and other applications. [ABSTRACT FROM AUTHOR]