The present work investigates the tribological properties of solid particles as lubricant additives in lubricants. Two types of solid particles, Ceria nanoparticles (CeO2) and Zinc borate ultrafine powders (ZB UFPs), were used as the lubricant additives in this study. The friction and wear behaviours of these lubricant additives in different base lubricants were identified. With an appropriate application of these solid lubricant additives, the friction reduction and wear resistance properties of the lubricant have been successfully improved. Without assistance of surfactant or surface modification, the two types of solid particles behave very differently. Evident performance was observed that pure ZB UFPs were capable of considerably reducing the friction coefficient of sunflower oil and liquid paraffin when they were used as a lubricant additive without further treatment. On the contrary, CeO2 nanoparticles did not show noticeable contribution to friction reduction when they were used as the only additive in water. Only when surfactant Sorbitan monostearate was employed to enhance the dispersibility of CeO2 nanoparticles in water, the application of this additive was capable of reducing friction coefficient of the water based lubricant effectively. Surface modification of the solid particles was carried out to improve the dispersibility of these particles in base lubricants. Oleic acid (OA) and Hexadecyltrimethoxysilane (HDTMOS) were selected as the modification agents. Modified CeO2 nanoparticles and ZB UFPs revealed outstanding wear resistance property. An improvement of up to 15 times was identified although this improvement on wear resistance, in this case, was often companied by a rise in friction coefficient. Tribo-films generated by tribo-chemical reaction were observed on most of the worn surfaces and the formation of this tribo-film appeared to have played an important role in the friction and wear behaviours of a system. A tenacious tribo-film with good surface coverage was only generated on the worn surface when HDTMOS modified solid particles were used as lubricant additives. The mechanical properties and elemental composition of the tribo-film were studied with nano-indentation and energy-dispersive X-ray spectroscopy (EDS). Finally, based on the experimental evidence, different functionalities of CeO2 nanoparticles and ZB UFPs as solid lubricant additives were recognized.

Poly(vinyl alcohol) (PVA) is a polymer used in numerous applications, principally those in which its high water solubility is a desirable asset. However there are also areas where PVA is limited by its inherent solubility (for example some specific environments in the biomedical field). This work has sought to overcome such limits by manipulating the surface of PVA in order to propose various means by which the surface solvent resistance might be increased while maintaining the bulk properties of the polymer. Both chemical and physical modifications have been tried and in each case progress has been made towards insolubilizing a single surface of the polymer when in film form. Grafting various species onto the surface of PVA was successfully performed. It is believed that such species bonded to the PVA via attachment to the hydroxyl groups (though this has not been proven conclusively). The data contained herein has led to the conclusion that the primary factor in reducing solubility this way is the removal of the hydroxyl groups, and not the attachment of specifically highly hydrophobic molecules. Introducing permanent cross-links into the surface region has been attempted via various routes. The data recorded shows promise however the system is far from optimised. The biggest challenge remaining is to optimise the depth of material cross-linked. Some steps have been made towards understanding and controlling this parameter though there is much scope for further investigation. The methods used have built on those used for bulk cross-linking and as such are new for the case of surface specific treatment. An interesting phenomenon in some semi-crystalline polymers reported in recent years is that of surface specific crystallization. This effect has been successfully induced and observed in PVA to produce what is believed to be a highly crystalline surface layer, and crystalline regions of PVA are generally accepted to be more water resistant than amorphous ones. In summary, in this work several surface-specific treatments for PVA have been trialled, providing options for post-film forming modification to reduce the surface water sensitivity whilst retaining the bulk properties of the polymer.

This thesis concerns the electrochemical investigation of high-potential laccases. These multicopper oxidases are efficient electrocatalysts for the dioxygen reduction reaction. A method for stabilising laccase on a graphite electrode was established. The method involved modification of the graphite surface by diazonium coupling of a 2-anthracene molecule. A laccase ‘film’ adsorbed on this modified surface remained stable for over two months and, typically, the current density for dioxygen reduction was doubled compared to a laccase ‘film’ on an unmodified surface. Protein film voltammetry was used to investigate thermodynamic and kinetic aspects of the electrochemical behaviour of laccase. The effect of inhibitors on the magnitude of reduction current and the position of the wave (related to the overpotential for the reaction) was also studied. Fluoride, chloride and azide showed different modes of inhibition and inhibition constants ranged from micromolar for azide to millimolar for chloride. In cyclic voltammetry experiments it was only in the presence of high concentrations of the inhibitors fluoride, chloride and azide that a non-turnover signal, corresponding to a one electron transfer process, was revealed. The evidence suggested that the non-turnover signal arose from interfacial electron transfer between the electrode and the type 1 or ‘blue’ copper. Evaluation of the peak areas allowed determination of the catalytic rate constant, kcat, as 300 s–1, and the electroactive surface coverage as four pmol cm–2. The rate of interfacial electron transfer was rapid enough to not limit catalysis at high overpotentials. A spectroelectrochemical cell was designed to investigate the behaviour of the type 1 copper in the presence of inhibitors and at different pH values. The inhibitors fluoride, chloride and azide had little effect on the reduction potential of the type 1 copper, but at higher pH values the reduction potential of the type 1 copper was decreased.

Hydrothermal method of nanoparticle preparation, involving oleic acid, has received certain attention in the last years. However, the published works lack systematic approach to the subject, and the mechanism was not thoroughly investigated, so as to achieve a predictable outcome of the synthesis. The present work investigated the influence of composition of organic and water phase on the synthesis of cobalt ferrite (cobalt(II)-iron(III) oxide) and magnetite nanoparticles, and the mechanism of nanoparticle formation was proposed. Organic phase was based on pentanol, octanol or toluene, containing the precursor - metal oleate. Besides hydrophobic particles, it was even possible to directly prepare hydrophilic oleate-coated particles by using water phase with sodium oleate. Synthetic procedure was then simplified by a separate preparation of cobalt-iron oleate, which led also to a product of narrower size distribution and better phase purity. Size control in the range of 6-11 nm and a batch yield of ca. 500 mg was achieved. Attention was given also to the surface modification of the particles, thus imparting them hydrophilicity. Small di- or tricarboxylic acids were utilized, as well as carboxylmethyl dextran and titanium dioxide. Titanium dioxide required additional protection with...

A síntese de nano partículas e a sua caracterização tem sido a grande mola propulsora do desenvolvimento de materiais nano-estruturados. Pouca atenção tem sido dedicada aos fenômenos físico-químicos relacionados às enormes superfícies intrínsecas destes materiais. Dentre eles, o titanato de bário ocupa uma posição de destaque devido ao seu grande potencial na geração de produtos de alta tecnologia. Neste estudo o BaTiO3 foi sintetizado pelo método Pechini que proporciona a geração de nanopartículas de grande uniformidade química. Contudo, o uso de cátions que formam carbonatos de alta estabilidade pode inviabilizar o uso do método. Os pós de titanato de bário preparados apresentaram elevada área de superfície específica, mas formação de fases parasitas de carbonato de bário e em algumas estequiometrias de ortotitanato de bário e carbonatos adsorvidos à superfície do titanato de bário. O estudo sistemático da química de superfície e da estrutura cristalina do material permitiu a proposta de um método de lixiviação em meio ácido onde as fases parasitas foram eliminadas e um material nanométrico de grande potencial de aplicação foi obtido com as seguintes características: fase com simetria tetragonal predominante ~95% (apesar da coexistência de fase cúbica ~5%); tamanho de cristalito ou partícula primária de 44 nm; área de superfície específica igual a 13,4 m2/g e D(BET) de 74 nm; está isento de contaminação de carbonatos ou outra fase; relação estequiométrica de Ba/Ti = 0,96 -> Ba0,98Ti1,02O3. / The synthesis and characterization of Nanoparticles has been a great topic for nanostructured materials developments. The Relationship between Physicochemical phenomena and large surface area has had a little attention. The barium titanate has a great potential of high-tech products generation. In this work, the BaTiO3 was prepared by polymeric precursor method because this method generates a great chemical uniformity in nanoparticles. However, cations that form carbonates of high-stability may compromise this method use. The barium titanate powder was prepared and showed high specific surface area, but this powder has barium carbonate and ortotitanato contamination. The systematic surface chemistry and crystal structure study suggest an acid leaching method to contaminant phases eliminated. A nanomaterial of great potential for application was obtained with the following characteristics: tetragonal phase predominant ~95% (cubic phase coexist ~5%); crystallite size of 44 nm; surface area of 13,4 m2/g and Particle size (estimated BET) of 74 nm; carbonate free; Ba/Ti = 0,96 -> Ba0,98Ti1,02O3.

Neste trabalho exploramos o uso de diferentes técnicas de microestruturação de materiais poliméricos a laser, visando a obteção de superfícies que podem ser aplicadas tanto no desenvolvimento de dispositivos fotônicos quanto de materiais biomédicos. Primeiramente, estudamos a influência da energia de pulso e velocidade de translação sobre as microestruturas produzidas na superfície de filmes de poli(2-metóxi-5-(2-etil-hexiloxi)-1,4-fenileno vinileno) (MEH-PPV). Observamos que a rugosidade da superfície microestruturada aumentou significativamente com o aumento da energia de pulso e velocidade de translação. Além disso, determinamos o limiar de energia para remoção de material, distinguindo o intervalo de energia para a remoção do polímero daquele que causa somente alterações morfológicas. Uma vez que as condições de microestruturação com pulsos laser de femtossegundos foram determinadas, aplicamos tal abordagem para fabricar um dispositivo eletroluminescente microestruturado, sem danificar o polímero e a camada de óxido de índio-estanho, utilizada como contato. Em uma segunda vertente do trabalho, estudamos a influência da energia do pulso ultracurto sobre as propriedades físico-químicas de filmes de quitosana. Neste caso, determinamos o limiar de energia para que ocorra mudança estrutural e remoção de material polimérico. Com isso, produzimos microestruturas com características mais hidrofílicas, além de superfícies com diferentes estruturações superficiais, que foram utilizadas para investigar seu potencial no estudo da formação de biofilme de Staphylococcus aureus. Neste caso, produzimos microestruturas com dimensões de 500 μm2 e diferentes periodicidades (variando de 4 a 12 μm) na superfície de filmes de quitosana e polimetilmetacrilato (PMMA). Com essas microestruturas, observamos distintos comportamentos para a formação de biofilme; no caso do PMMA, não houve distinção de desenvolvimento; quanto às amostras de quitosana, observamos uma preferência das bactérias por superfícies mais rugosas e regiões de bordas das microestruturas. Por fim, em uma terceira vertente do trabalho, utilizamos o método de estruturação direta por interferência para fabricar microestruturas periódicas em membranas de poliuretano, usando pulsos de nanossegundos. Com esse método, produzimos microestruturas de alta qualidade na superfície de membranas de poliuretano, com diferentes periodicidades (variando de 500 nm até 5 μm). Essa microestruturação permitiu a obtenção de amostras com comportamento de molhamento anisotrópico. De maneira geral, os resultados aqui apresentados, além de demonstrar a potencialidade das técnicas de microfabricação a laser, fornecem importantes informações sobre os parâmetros ótimos para microfabricação em filmes poliméricos, visando aplicações tanto em dispositivos fotônicos e optoeletrônicos quanto em biomateriais. / In this work we explored the use of laser micromachining methods to structure polymeric materials, aiming to obtain surfaces that can be applied in the development of photonic devices as well as biomedical materials. Firstly, we investigated the influence of pulse energy and translation speed on microstructures fabricated on the surface of poly[2-methoxy-5- (2\'-ethylhexyloxy)-p-phenylenevinylene] (MEH-PPV) films. We observed that the roughness of the microstructured surface significantly increased with the pulse energy and translation speed. Besides, we determined the energy threshold for material removal, distinguishing the energy range for polymer removal from that causing only structural changes. Once the proper laser micromachining conditions were determined, we were able to apply such approach to fabricate a functional microstructured electroluminescent device, without disrupting the indium tin oxide layer used as the contact for the devices. In the second part of the work, we studied the influence of femtosecond pulses on the structuring process of chitosan films. In this case, we determined the threshold energy that leads to structural change and material removal. We have been able to produced microstructures with hydrophilic characteristics, in addition to surfaces with different structuring that were used to study the formation of Staphylococcus aureus biofilm. For such purpose we produced microstructured areas of 500 μm2 and different periods (ranging from 4 to 12 μm) on the surface of chitosan and poly(methyl methacrylate)(PMMA) films. With these microstructures we observed different behaviors in the biofilm formation; in the case of PMMA, there was not distinction of development; concerning the chitosan samples we observed preferential bacterial growth on the rougher regions of the microstructures. Lastly, in a third part of the study, we used the method of direct laser interference patterning to fabricate periodic microstructures on polyurethane membranes, using nanosecond pulses. With this method, we produced high quality microstructures on the surface of polyurethane with different periodicity (from 500 nm to 5.0 μm). This approach allowed obtaining samples with anisotropic wetting behavior. In general, the results presented here, in addition to demonstrating the potential of the laser micromachining methods to structure polymeric samples, provides important information about the optimal parameters to micromachining of polymer films, aiming at applications in photonic devices, optoelectronics and biomaterials.

Implantes de titânio têm sido extensivamente utilizados na Ortopedia e na Odontologia, principalmente como substitutos de elementos dentários ausentes. O titânio é um implante metálico de escolha devido à sua alta biocompatibilidade e resistência à corrosão, e também porque não provoca reações imunológicas, ao mesmo tempo em que promove a osseointegração. A biocompatibilidade do implante depende da resposta celular em contato com a sua superfície; sendo assim, mudanças nesta superfície podem provocar impactos benéficos na osseointegração através de alterações nas interações com as células presentes no local do implante, como, por exemplo, células osteoblásticas. O objetivo do presente trabalho foi caracterizar a resposta celular de células osteoblásticas humanas provenientes da crista óssea alveolar em contato com diferentes superfícies de titânio: controle (polido), nanotextura, nano+submicrotextura e microtextura rugosa. Os ensaios bioquímicos realizados foram: proliferação e viabilidade celular, quantidade de proteína total e atividade de fosfatase alcalina, além da detecção e quantificação de nódulos mineralizados, com a utilização do teste estatístico não paramétrico de Kruskal-Wallis e de Mann-Whitney com p≤0,05. Também foi realizada a avaliação da modulação gênica nas células em contato com as diferentes superfícies de titânio por meio do método de oligo microarray, utilizando lâminas Agilent formato 4x44 K e análise de microRNAs utilizando lâminas Agilent 8x15 K. A fim de identificar alterações na expressão gênica foi utilizado o programa GeneSpring GX. A expressão gênica foi validada pela reação de PCR quantitativa em tempo real (qRT-PCR). Observamos um pico na proliferação celular aos 10 dias de cultura e um aumento gradual da viabilidade celular ao longo do tempo. Entre as superfícies tratadas observou-se maior quantidade de proteína total na nanotextura em relação à nano+submicrotextura aos 10 dias de cultura (p≤0,05) e um aumento progressivo da atividade de fosfatase alcalina, com maior atividade na nanotextura em relação à nano+submicrotextura aos 14 dias de cultura (p≤0,05). Não houve diferença qualitativa na formação dos nódulos mineralizados, apesar de a microtextura rugosa apresentar maior quantidade de cálcio que a nanotextura (p≤0,05). Os resultados encontrados evidenciaram expressão diferenciada de 716 mRNAs (fold change≥2,0 e p≤0,05) e 32 microRNAs (fold change≥1,5 e p≤0,01) com funções associadas ao processo de osteogênese, principalmente mineralização, adesão celular, apoptose, proliferação e diferenciação celular. Os resultados sugerem que, diante do protocolo utilizado neste trabalho, o tratamento químico realizado na superfície do titânio provoca variações no metabolismo de células osteoblásticas tanto em nível celular como de expressão gênica / Titanium implants have been extensively used in orthopedics and dentistry, mainly as a replacement for missing teeth. Titanium is the metal implant of choice due to its high biocompatibility and corrosion resistance, as well as absence of immune response, while promoting osseointegration. The biocompatibility of the material depends on cellular response in contact with the surface; therefore, changes on this surface can have beneficial impacts on osseointegration through changes in interactions with cells at the implant site, such as osteoblastic cells. The objective of this study was to characterize the cellular response of osteoblastic cells from human alveolar crest in contact with different titanium surfaces: control (polished), nanotextured, nano+submicrotextured and rough microtexture. The performed biochemical assays included cell proliferation and viability, total protein content and alkaline phosphatase activity, in addition to the detection and quantification of mineralized nodules, using the non-parametric statistical tests of Kruskal-Wallis and Mann-Whitney (p≤0,05). Osteoblastic gene modulation was evaluated by means of an oligo microarray method using Agilent format 4 x 44 K slides and Agilent 8x15 K slides for microRNAs analysis. In order to identify changes in gene expression, it was used the GeneSpring GX program. Gene expression was validated by quantitative PCR real time (qRT-PCR). It was observed a peak in cell culture proliferation at 10 days and a gradual increase in cell viability over the periods. Among the treated surfaces, we observed an increase in the amount of total protein in nanotextured when compared to nano+submicrotextured at 10 days of culture (p≤0,05), and a progressive increase of alkaline phosphatase activity, with higher activity in nanotextured compared to nano+submicrotextured at 14 days of culture (p≤0,05). There was no qualitative difference among the groups with regards to mineralized nodules, although the rough microtexture group showed higher amounts of calcium than the nanotextured group (p≤0,05). Our results showed a differential expression of 716 mRNAs (fold change≥2,0 and p≤0,05) and 32 microRNAs (fold change≥1,5 and p≤0,01), with functions associated to the osteogenesis process, mainly mineralization, cell adhesion, apoptosis, cell proliferation and differentiation. The results suggest that, with the protocols used in this investigation, the treatments performed in the titanium surface induce changes in the metabolism of osteoblastic cells, both at the cellular as well as at the gene expression levels

Este trabalho foi desenvolvido em duas etapas: i) síntese, caracterização e aplicação de pontos quânticos de CdS, CdSe e CdTe em células solares. ii) modificação da superfície dos pontos quânticos de CdSe através de troca de ligante, seguida de caracterização e aplicação em células solares. Os pontos quânticos foram sintetizados utilizando acetatos de cádmio, selênio, telúrio e enxofre como precursores e ácido oleico como agente de estabilização. Na segunda etapa o ácido oleico foi substituído por ligantes com maior afinidade eletrônica pelos sítios de Cd2+: ácido 3-mercaptopropiônico, 4-ácido-mercaptobenzóico e ácido 11-mercaptoundecanóico. As amostras foram caracterizadas por UV-Vis, fluorescência, microscopia eletrônica de transmissão, difratometria de raios-X e voltametria cíclica. Adicionalmente, testes de solubilidade, análises de TGA e de RMN foram realizadas para confirmar a troca de ligante. Através dos resultados, verificou-se que todos os pontos quânticos sintetizados são adequados para sensibilização de TiO2 em dispositivos fotovoltaicos. No entanto, os pontos quânticos de CdSe e CdTe apresentaram fatores que evidenciam maior confinamento quântico, sendo que a maior estabilidade do éxciton foi obtida para o CdSe. Através das análises de RMN foi possível verificar que não existe apenas uma confirguração espacial preferencial para a adsorção do ligante sobre a superfície deste ponto quântico enquanto que curvas de corrente versus potencial e de eficiência de conversão de fóton incidente mostraram que a eficiência do dispositivo é fracamente dependente do ligante. Contudo, a troca de ligantes favorece a solubilidade em solventes com diferentes polaridades, inclusive água, o que amplia as possibilidades de aplicação dos pontos quânticos sintetizados neste trabalho. / This work was developed in two stages: i) synthesis, characterization and application of CdS, CdSe and CdTe quantum dots to assemble solar cells, ii) surface modification, characterization and application of CdSe quantum dots to assemble solar cells. The quantum dots were synthesized by using cadmium acetate, Se, S or Te as precursors and oleic acid as stabilizing agent. In the second stage the oleic acid capping layer was replaced by other ligands with higher electron affinity to Cd2+: 3-mercaptopropionic acid, 4-mercaptobenzoic acid and 11-mercaptoundecanoic acid. The samples were characterized by UV-Vis, fluorescence, transmission electron microscopy, x-ray diffractometry and cyclic voltammetry. Additionally, solubility tests, TGA analysis and NMR were performed to evaluate the CdSe surface modification. The results showed that all quantum dots synthesized are adequate to sensitize TiO2 in photovoltaic devices. However, CdSe and CdTe quantum dots presented better quantum confinement and the exciton generated in CdSe presented the higher stability. NMR analysis provided information about the non-preferential orientation for adsorption of the ligands on the CdSe surface, meanwhile measurements of current vs. potential and incident photon current efficiency showed a weak dependence of photovoltaic device efficiency with the nature of the ligand. On the other side, the surface modification favors the solubility in solvents with different polarizabilities, including water, widening the range for applications of the quantum dots synthesized in this work.

<p>Membrane gas absorption technology is considered as one of the promising alternatives to conventional techniques for CO₂ separation from the flue gas of fossil fuels combustion. As a hybrid approach of chemical absorption and membrane separation, it may offer a number of important features, including operational flexibility, compact structure, linear scale up and predictable performance. The main challenge is the additional membrane mass transfer resistance, especially when this resistance increases due to the absorbent intruding into the membrane pores.</p><p>In this thesis, the experimental was set up to investigate how the operating parameters affect the absorption performance when using absorbent in hollow fiber contactor, and to obtain the optimal range of operation parameters for the designated membrane gas absorption system . During 20 days’ continuous experiment, we observed that the CO₂ mass transfer rate decreases significantly following the operating time, which is attributed to the increase of membrane mass transfer resistance resulting from partial membrane wetting.</p><p>To better understand the wetting evolution mechanism, the immersion experiments were carried out to assume that the membrane fibers immersed in the absorbents would undergo similar exposure as those used in the membrane contactor. Various membrane characterization methods were used to illustrate the wetting process before and after the membrane fibers were exposed to the absorbents. The characterization results showed that the absorbent molecules diffuse into the polypropylene (PP) polymer during the contact with the membrane, resulting in the swelling of the membrane. In addition, the effects of operating parameters such as immersion time, CO₂ loading, as well as absorbent type on the membrane wetting were investigated in detail. Finally, based on the analysis results, methods to smooth the membrane wetting were discussed. It was suggested that improving the hydrophobicity of PP membrane by surface modification may be an effective way to improve the membrane long-term performance.</p><p>Modification of the polypropylene membrane by depositing a rough layer of PP was carried out in order to improve the non-wettability of membrane. The comparison of long-term CO₂ absorption performance by PP membranes before and after modification proves that the modified polypropylene membranes retained higher hydrophobicity than the untreated polypropylene membrane. Therefore modification is likely to be more suitable for use in membrane gas absorption contactors for CO₂ separation, particularly over long operation time.</p>

This thesis is concerned with the fabrication methodology of polymeric photonic crystals operating in the visible to near infrared regions and the correlation between the chemical deposition morphologies and the resultant photonic stopband enhancements of photonic crystals. Multiphoton lithography (MPL) is a powerful approach to the fabrication of polymeric 3D micro- and nano-structures with a typical minimum feature size ~ 200 nm. The completely free-form 3D fabrication capability of MPL is very well suited to the formation of tailored photonic crystals (PCs), including structures containing well defined defects. Such structures are of considerable current interest as micro-optical devices for their filtering, stop-band, dispersion, resonator, or waveguiding properties. More specifically, the stop-band characteristics of polymer PCs can be finely controlled via nanoscale changes in rod spacings and the chemical functionalities at the polymer surface can be readily utilized to impart new optical properties. Nanoscale features as small as 65 ± 5 nm have been formed reproducibly by using 520 nm femtosecond pulsed excitation of a 4,4'-bis(di-n-butylamino)biphenyl chromophore to initiate crosslinking in a triacrylate blend. Dosimetry studies of the photoinduced polymerization were performed on chromophores with sizable two-photon absorption cross-sections at 520 and 730 nm. These studies show that sub-diffraction limited line widths are obtained in both cases with the lines written at 520 nm being smaller. Three-dimensional multiphoton lithography at 520 nm has been used to fabricate polymeric woodpile photonic crystal structures that show stop bands in the visible to near-infrared spectral region. 85 ± 4 nm features were formed using swollen gel photoresist by 730 nm excitation MPL. An index matching oil was used to induce chemical swelling of gel resists prior to MPL fabrication. When swollen matrices were subjected to multiphoton excitation, a similar excitation volume is achieved as in normal unswollen resins. However, upon deswelling of the photoresist following development a substantial reduction in feature size was obtained. PCs with high structural fidelity across 100 µm × 100 µm × 32 layers exhibited strong reflectivity (>60% compared to a gold mirror) in the near infrared region. The positions of the stop-bands were tuned by varying the swelling time, the exposure power (which modifies the feature sizes), and the layer spacing between rods. Silver coatings have been applied to PCs with a range of coverage densities and thicknesses using electroless deposition. Sparse coatings resulted in enhanced reflectivity for the stop band located at ~5 µm, suggesting improved interface reflectivity inside the photonic crystal due to the Ag coating. Thick coatings resulted in plasmonic bandgap behavior with broadband reflectivity enhancement and PC lattice related bandedge at 1.75 µm. Conformal titania coatings were grown onto the PCs via a surface sol-gel method. Uniform and smooth titania coatings were achieved, resulting in systematically red-shifted stopbands from their initial positions with increasing thicknesses, corresponding to the increased effective refractive index of the PC. High quality titania shell structures with modest stopbands were obtained after polymer removal. Gold replica structures were obtained by electroless deposition on the silica cell walls of naturally occurring diatoms and the subsequent silica removal. The micron-scaled periodic hole lattice originated from the diatom resulted in surface plasmon interferences when excited by infrared frequencies. The hole patterns were characterized and compared with hexagonal hole arrays fabricated by focused ion beam etching of similarly gold plated substrate. Modeling of the hole arrays concluded that while diatom replicas lack long-ranged periodicity, the local hole to hole spacings were sufficient to generate enhanced transmission of 13% at 4.2 µm. The work presented herein is a step towards the development of PCs with new optical and chemical functionalities. The ability to rapidly prototype polymeric PCs of various lattice parameters using MPL combined with facile coating chemistries to create structures with the desired optical properties offers a powerful means to produce tailored high performance photonic crystal devices.