Potential of building integrated and attached/applied photovoltaic (BIPV/BAPV) for adaptive less energy-hungry building’s skin: A comprehensive review

A novel composition for a low-toxicity, water-soluble, holographic photopolymer capable of recording bright reflection gratings with diffraction efficiency of up to 50% is reported. The unique combination of two chemical components, namely, a chain transfer agent and a free radical scavenger, is reported to enhance the holographic recording ability of a diacetone acrylamide (DA)-based photopolymer in reflection mode by 3-fold. Characterization of the dependence of diffraction efficiency of the reflection gratings on spatial frequency, recording intensity, exposure energy, and recording wavelength has been carried out for the new low-toxicity material. The use of UV postexposure as a method of improving the stability of the photopolymer-based reflection holograms is reported. The ability of the modified DA photopolymer to record bright Denisyuk holograms which are viewable in different lighting conditions is demonstrated.

Low-Toxicity Photopolymer for Reflection Holography

A facile biomimetic approach for the synthesis of gold nanoparticles (AuNPs) using aqueous extract of fennel (Foeniculum vulgare) seeds have been reported in this article. The seeds of F. vulgare are rich in various plant secondary metabolites (phytochemicals) such as polyphenolic acids, flavonoids, and saponins. The phytochemicals of F. vulgare seeds play dual role of reducing and stabilizing agents. The formation of gold nanoparticles was evidenced from the appearance of intense purple color at room temperature with λ
 max around 550 nm in the UV–Vis absorption spectra. The stable AuNPs were further characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and transmission electron microscopy (TEM) analysis. The synthesized nanoparticles were observed to be polydispersed, spherical and ranged from 10 to 30 nm with an average size of 20 ± 2 nm, as obtained from TEM images. The catalytic activity of gold nanoparticles was investigated by studying the reduction of anthropogenic dyes such as methylene blue (MB) and rhodamine B (Rh-B) with sodium borohydride. Results showed the possible applications of biogenic AuNPs in environment related problems.

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A biomimetic synthesis of stable gold nanoparticles derived from aqueous extract of Foeniculum vulgare seeds and evaluation of their catalytic activity

The results of studies that have been performed over the last decade in the field of development of silver halide and nonsilver holographic recording media of organic and inorganic origin are analyzed. It is shown that previously developed materials mainly allow the development of holographic investigations. Among irreversible materials, considerable progress has been made in improving the characteristics of photopolymerizable recording media, which has allowed their use in color image holography and 3D optical archive-type memory, as well as for fabricating holographic optical elements. In the field of improving the properties of reversible holographic recording media, practically significant results have been obtained for the creation of photoanisotropic materials based on azo dyes experiencing cis–trans photoisomerization, which allow the recording of polarization holograms. The needs of dynamic holography have been satisfied by lightsensitive doped inorganic crystals and polymer layers that have been created with nonlinear optical properties.

The Current Status of the Development of Light-Sensitive Media for Holography (a Review)

Increasing photosensitizer concentration has been considered as an effective approach to improve the performance of holographic material. In this paper, we report on new method for increasing the saturated dissolvability of photosensitizer PQ within polymeric media by introducing copolymerization monomer into the PQ/PMMA. The photosensitizer concentration of PQ was increased from 0.7wt% to 1.3wt%, compared with the typical PQ/PMMA sample. Besides, we investigated performance of polarization holographic recordings in typical PQ/PMMA and copolymerization monomer-containing PQ/PMMA with the orthogonally polarized signal and reference waves. And the doping of THFMA component resulted in a significant improvement of diffraction intensity and photosensitivity. In addition, high-quality holographic image reconstruction was realized in our home-made material.

Improving the polarization-holography performance of PQ/PMMA photopolymer by doping with THMFA.

Improving the performance of methylene blue sensitized photopolymer by doping with nickel ion

Designing photovoltaic concentrators using holographic lens recorded in nickel ion doped photopolymer material

In the present study, a series of holographic gratings were recorded in a single location of nickel-ion-doped photopolymer film using different methods of multiplexing. The uniformity of their diffraction efficiency was shown to improve by using an exposure time scheduling method for holographic recording. Thirty-five gratings were recorded in the 130 μm thick photopolymer material with M#=6.18 and an average diffraction efficiency of 3.24% using peristrophic multiplexing. In the next step, a combination of peristrophic and angular multiplexing was used for storing 50 gratings in the material with a dynamic range of 7 and a mean diffraction efficiency of 2.15%.

Multiplexing recording in nickel-ion-doped photopolymer material for holographic data storage applications.

Photopolymer systems can produce good image quality holograms that does not require any post-processing and are environmentally stable with good diffraction efficiency The present work reports the development of a methylene blue-sensitized polyvinyl alcohol acrylamide (MBPVA/AA) photopolymer system for recording white light reflection holograms Reflection gratings were recorded in the photopolymer films with different concentrations of methylene blue (MB) Various parameters affecting the holographic properties of the samples were also studied The holographic performance of the material is found to depend on its chemical composition and the recording parameters

Reflection mode holographic recording in methylene blue-sensitized polyvinyl alcohol acrylamide films

The limited absorption range of photopolymers in the visible region was always a matter of concern due to their wide-spread application in the field of holography. The present work has investigated the possibility of extending the limited absorption range towards the entire visible range by simple modifications in the photopolymer composition so that panchromaticity can be invoked in the material. Here modification was done on already developed photopolymer material by adding another photosensitizer. Studies showed that holographic performance was improved to a great extent. It was possible to record gratings with blue, green and red wavelengths in 130 µm thick films with more than 80% diffraction efficiency (DE) creating a refractive index modulation of ∼1.7 × 10−3 at exposure energy of 50 mJ/cm2. This material will be a good candidate for data storage and color holographic applications. One of the remarkable findings was that the storage and shelf life of the material could be extended compared to other photopolymer materials. This material could be used to write gratings with 70% DE even after 12 months of storage. Thus, addition of a second photosensitizer not only extended the absorption range, but also the shelf life of the photopolymer.

C.S. Rajesh

Papers

Improving the performance of methylene blue sensitized photopolymer by doping with nickel ion

Designing photovoltaic concentrators using holographic lens recorded in nickel ion doped photopolymer material

Multiplexing recording in nickel-ion-doped photopolymer material for holographic data storage applications.

Reflection mode holographic recording in methylene blue-sensitized polyvinyl alcohol acrylamide films

Stretching the sensitivity and stability of an acrylamide based photopolymer material with mixture of dyes