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Organic photovoltaic (OPV) technology has recently achieved remarkable progress in academia, attaining power conversion efficiencies exceeding 19%, a breakthrough previously unimaginable. Despite these advancements, the translation of high‐efficiency OPV cells into the commercialization of OPV modules has been limited, impeding the market penetration of OPV technology. Upon careful examination, various challenges emerge, including disparities between laboratory research and industrial production in device architecture, influenced by considerations of cost and manufacturability. Additionally, the incorporation of high‐efficiency materials requires careful consideration not only of the compatibility between the photoactive layer and interface layers or transparent electrodes but also of the associated synthetic complexity of chemical structures and cost implications. While these issues are crucial, they may not be widely discussed in current mainstream research. In this article, the purpose is to identify bottlenecks from a material techniques perspective, with the aim of promoting increased resources in the research of pertinent module technologies. This effort is intended to propel OPV technology toward greater success and bring it into closer alignment with the goals of commercialization. [ABSTRACT FROM AUTHOR]

In this article, the electromagnetic shielding properties of carbon nanotube–polymer nanocomposites are presented. The composite fabrication technique is spray-drying, the usage of which leads to a uniform dispersion of carbon nanotubes (CNTs) in a polymer matrix. Obtaining good filler dispersion is necessary to form a continuous, electrically conductive network of CNTs inside the polymer matrix. In the described nanocomposites, the network of conductive filler particles acts as an electromagnetic radiation barrier. For this reason, developing a highly effective fabrication method is very important. Also, the method should be simple enough to be easily adopted in an industrial environment. The authors shows in this text that both goals mentioned are achieved. The obtained nanocomposite material not only has electrostatic shielding capabilities but comprises electromagnetic shielding properties, which fulfills the main goal of the presented work. It is also worth mentioning that the developed manufacturing method allows for the usage of different fillers and polymers and thus the fabrication of materials capable of meeting a wide range of requirements. [ABSTRACT FROM AUTHOR]

With the development in the early 2000s of new cluster ion sputtering sources, a reliable analysis of organic multilayers and interfaces has become possible. Nowadays, time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and X‐ray photoelectron spectroscopy (XPS) depth profiling are routinely used to investigate organic stacks. However, analysis beams can cause bond scission or beam‐induced degradations that accumulate in buried layers. We developed a correlative protocol that minimises damages related to analysis beams. It uses a shallow angle bevel crater fabricated inside the ToF‐SIMS analysis chamber. With this preparation method, the in‐depth information is displayed over the surface of the bevel crater. XPS profiles and high‐resolution spectra paired with ToF‐SIMS images enable an easy identification of the organic layers and complete understanding of their chemistry. The reduction of beam‐induced degradation is achieved by minimising the acquisition times, therefore beam exposure on materials. Finally, an important advantage of this preparation method is that the analysis can be performed on exactly the same spot by multiple techniques. Several ToF‐SIMS and XPS acquisitions can be carried out with various parameters (investigation of backscattered Arn+ cluster ion fragments, tandem MS imaging...) as well as analysis with other techniques that possess limitations in spatial resolution and/or inaptitude to probe buried layers such as Raman or AFM. [ABSTRACT FROM AUTHOR]

As membrane-mediated antibiotic resistance continues to evolve in Gram-positive bacteria, the development of new approaches to elucidate the membrane properties involved in antibiotic resistance has become critical. Membrane vesicles (MVs) secreted by the cytoplasmic membrane of Gram-positive bacteria contain native components, preserving lipid and protein diversity, nucleic acids, and sometimes virulence factors. Thus, MV-derived membrane platforms present a great model for Gram-positive bacterial membranes. In this work, we report the development of a planar bacterial cytoplasmic membrane-based biosensor using MVs isolated from the Bacillus subtilis WT strain that can be coated on multiple surface types such as glass, quartz crystals, and polymeric electrodes, fostering the multimodal assessment of drug–membrane interactions. Retention of native membrane components such as lipoteichoic acids, lipids, and proteins is verified. This biosensor replicates known interaction patterns of the antimicrobial compound, daptomycin, with the Gram-positive bacterial membrane, establishing the applicability of this platform for carrying out biophysical characterization of the interactions of membrane-acting antibiotic compounds with the bacterial cytoplasmic membrane. We report changes in membrane viscoelasticity and permeability that correspond to partial membrane disruption when calcium ions are present with daptomycin but not when these ions are absent. This biomembrane-based biosensing platform enables an assessment of membrane biophysical characteristics during exposure to antibiotic drug candidates to aid in identifying compounds that target membrane disruption as a mechanism of action. [ABSTRACT FROM AUTHOR]

• Optoelectronic properties of β-Cyclodextrin (β-CD) and doped with Na are studied. • Obtained band gaps are 3.44 and 4.14 eV by DFT and experiment, receptively. • Experimental results show that band gap value decreases by Na doping to 3.09 eV. • The s-p orbitals and C O covalent bonds contribute to stabilization of β-CD. • There is a good agreement between the obtained experimental and DFT spectra. The chemical and physical properties of β-Cyclodextrin (β-CD) and doped with Na can be useful in drug delivery, organic solar cells and photoprotective applications. Physicochemical properties of pure β-CD and doped with Na were investigated by both density functional theory (DFT) and experimental methods. Theoretical calculations and the experimental measurements revealed that β-CD has a direct band gap of 3.44 and 4.14 eV, respectively. The optical absorption measurements indicate that band gap value decreases by Na doping to 3.09 eV. DOS spectra confirmed the stabilization of β-CD by the strong covalent bonds between C and O atoms. Obtained small effective mass of charge carriers with the high carrier mobility in β-CD show that it is a good candidate for using in the organic electronic applications. The significant isotropic behavior was observed in all optical spectra. The positive values of the real part of dielectric function confirm the dielectric nature of β-CD. Maximum dielectric polarization is observed at the ultraviolet region with the static dielectric constant of 2.03. High reflectivity at the ultraviolet region and beyond that confirm the photoprotective properties of β-CD compound against harmful solar radiations. There is a good agreement between the obtained experimental and DFT spectra. Our findings may be useful in design of new organic optoelectronic devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Common organic small molecule dyes exhibit chemical modifiability and are easy to polymerize, making them potential monomers in organic electronics. The multifunctionality of organic synthetic chemistry allows for material adaptability. Here, we report the synthesis route and purification methods for dye polymer based on thiophene-diketopyrrolopyrrole. Their orderly conjugated structure and high coplanarity contribute to a high crystallinity, which is favorable for charge carrier transport. By adjusting the device structure and thin film preparation conditions, the hole transport properties of the materials were further optimized, achieving a maximum mobility of up to 0.35 cm2 V−1 s−1. The excellent charge carrier performance reveals the potential of such material for applications in organic electronics. [Display omitted] • High-yield synthesis of dye-based organic electronic materials. • Highly coplanar structure with solution processing method. • Achieving high mobility relies on device structure and annealing temperature modulation. [ABSTRACT FROM AUTHOR]

Organic compounds have been employed in developing new green energy solutions with good cost-efficiency compromise, such as photovoltaics. The light-harvesting process in these applications is a crucial feature that still needs improvements. Here, we studied natural dyes to propose an alternative for enhancing the light-harvesting capability of photovoltaics. We performed density functional theory calculations to investigate the electronic and optical properties of the four natural dyes found in achiote seeds (Bixa orellana L.). Different DFT functionals, and basis sets, were used to calculate the electronic and optical properties of the bixin, norbixin, and their trans-isomers (molecules present in Bixa orellana L.). We observed that the planarity of the molecules and their similar extension for the conjugation pathways provide substantially delocalized wavefunctions of the frontier orbitals and similar values for their energies. Our findings also revealed a strong absorption peak in the blue region and an absorption band over the visible spectrum. These results indicate that Bixa orellana L. molecules can be good candidates for improving light-harvesting in photovoltaics. [ABSTRACT FROM AUTHOR]

Stretchable and flexible electrodes are desirable for use in mobile and wearable devices. When one surface of a fabric is non-conductive and the other surface is electrochemically active, such a fabric could potentially be used as an electrode in an electrochemical application without a separator because the non-conductive surface would prevent short circuits between the electrodes. In this study, a stretchable fabric with a conductive surface that has been knitted using Ag-coated filaments was cycled in aqueous (alkaline, acidic, and neutral) and non-aqueous (ionic liquid) electrolytes to study their electrochemical behaviors for their usability as energy storage devices. After study via cyclic voltammetry, KOH solution was selected as the most appropriate electrolyte among the four considered because the fabric showed stable oxidation and reduction peaks in this electrolyte after repetitive cycling. The Ag-based fabric electrode was also found to evolve (became stable) in this electrolyte. Electrochemical (cyclic voltammogram) and non-electrochemical (X-ray diffraction, scanning electron microscope, energy dispersive X-ray spectroscopy) characterization of the electrode were carried out. The cycling of stretchable fabric was stopped at the oxidized and reduced potential in KOH electrolyte in order to characterize the crystalline, morphological, and compositional structure of the electrode as dependent on the applied potential. The capacitances of the electrode remained similar when the timescale was increased 40-fold, indicating that the electrode has a high power density. The reaction between the fabric and OH− electrolyte was found to proceed as a ‘mixture’ of a surface- and a diffusion-controlled mechanism. The areal and specific capacitances of the electrode were found to be 46 mF cm−2 and 36 F g−1, respectively. The stretchable fabric with Ag-coated filaments could potentially be used as an electrode in a hydroxide-based electrolyte for stretchable and flexible energy storage devices. [ABSTRACT FROM AUTHOR]

Polymer‐based materials hold great potential for use in thermoelectric applications but are limited by their poor electrical properties. Through a combination of solution‐shearing deposition and directionally applied solvent treatments, poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin films with metallic‐like conductivities can be obtained with high power factors in excess of 800 µW m−1 K−2. X‐ray scattering and absorption data indicate that structural alignment of PEDOT chains and larger‐sized domains are responsible for the enhanced electrical conductivity. It is expected that further enhancements to the power factor can be obtained through device geometry and postdeposition solvent shearing optimization. [ABSTRACT FROM AUTHOR]

Organic compounds have been employed in developing new green energy solutions with good cost-efficiency compromise, such as photovoltaics. The light-harvesting process in these applications is a crucial feature that still needs improvements. Here, we studied natural dyes to propose an alternative for enhancing the light-harvesting capability of photovoltaics. We performed density functional theory calculations to investigate the electronic and optical properties of the four natural dyes found in achiote seeds (Bixa orellana L.). Different DFT functionals, and basis sets, were used to calculate the electronic and optical properties of the bixin, norbixin, and their trans-isomers (molecules present in Bixa orellana L.). We observed that the planarity of the molecules and their similar extension for the conjugation pathways provide substantially delocalized wavefunctions of the frontier orbitals and similar values for their energies. Our findings also revealed a strong absorption peak in the blue region and an absorption band over the visible spectrum. These results indicate that Bixa orellana L. molecules can be good candidates for improving light-harvesting in photovoltaics.

Molecular packing and microstructure can play a crucial role in the photophysical and electronic properties of organic semiconductor materials. This article presents six pyrene‐fused dibenzoazatetracenes 3 and the relationship between their molecular structures and the emission, and as well as the morphology has been investigated. All of the compounds display an aggregation‐caused emission quenching effect due to the extended π‐conjugation associated with the close π‐π stacking in their crystal structures. In terms of fluorescence, the compounds emitted sky‐blue emission with a maximum peak (λmaxem) in the range 469–474 nm with a quantum yield (Φf) of 0.37–0.50 in solution. In the solid state, the emission maximum red‐shifts to ∼528 nm and possesses a relatively low quantum yield (<0.16). In addition, the electronic effects of the terminal group shows only a limited effect on the emission behavior. On the other hand, tert‐butyl groups have been introduced at the pyrene core, and contribute to enhance the solubility of the compound, and also improve the quality of the morphology. [ABSTRACT FROM AUTHOR]

[Display omitted] • Six D-A conjugated polymers synthesized successfully in a continuous flow reactor. • Obtained high degree of polymerization (31 – 88) and excellent reproducibility. • High quality polymers synthesized using a single set of reaction parameters. • Flow synthesis as an ideal method to produce D-A conjugated polymers. Donor-acceptor (D-A) conjugated polymers often exhibit excellent performance in electronic and photonic applications, however, their synthesis remains a hurdle to achieving their wide-spread commercialization. While scalable and reproducible flow syntheses have emerged as promising candidates to address this issue, they have only been applied to a narrow scope of polymer types. In this study, we explore the synthesis of six different D-A conjugated polymers in a continuous flow reactor to determine how reaction and polymer parameters influence the degree of polymerization (DP) and quality of the resulting polymers. We found that we could successfully synthesize p -type, n -type, and ambipolar D-A conjugated polymers with a single set of reaction parameters. Only the reaction time required optimization to achieve high-DPs. Importantly, we found that we could achieve comparable DPs to batch reactions, but with higher yields and much shorter reaction times. High-quality polymers were also obtained, which was confirmed with optical and electrochemical properties measurements and by their performance in organic field-effect transistors. We expect this work to further establish flow synthesis as an ideal method to make D-A conjugated polymers, which may help facilitate their commercialization in high-performing organic devices. [ABSTRACT FROM AUTHOR]

Nonlinearity in current (I) – voltage (V) measurement is a well-known attribute of two-terminal organic device, irrespective of the geometrical or structural arrangement of the device. Most of the existing theories that are developed for interpretation of I–V data, either focus current-voltage relationship of charge injection mechanism across the electrode-organic material interface or charge transport mechanism through the organic active material. On the contrary, both the mechanisms work in tandem charge conduction through the device. The transport mechanism is further complicated by incoherent scattering from scattering centres/charge traps that are located at the electrode-organic material interface and in the bulk of organic material. In the present communication, a collective expression has been formulated that comprises of all the transport mechanisms that are occurring at various locations of a planar organic device. The model has been fitted to experimental I–V data of Au/P3HT/Au device with excellent degree of agreement. Certain physical parameters such as the effective area of cross-section and resistance due to charge traps have been extracted from the fit. [ABSTRACT FROM AUTHOR]

We report on the self-assembly of semicrystalline [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) nanosheets at the interface between a hydrophobic solvent and water, and utilize this opportunity for the realization of electronically active organic/organic molecular heterostructures. The self-assembled PCBM nanosheets can feature a lateral size of >1 cm² and be transferred from the water surface to both hydrophobic and hydrophilic surfaces using facile transfer techniques. We employ a transferred single PCBM nanosheet as the active material in a field-effect transistor (FET) and verify semiconductor function by a measured electron mobility of 1.2 × 10-2 cm² V-1 s-1 and an on-off ratio of ~1 × 104. We further fabricate a planar organic/organic heterostructure with the p-type organic semiconductor poly(3-hexylthiophene-2,5-diyl) as the bottom layer and the n-type PCBM nanosheet as the top layer and demonstrate ambipolar FET operation with an electron mobility of 8.7 × 10-4 cm² V-1 s-1 and a hole mobility of 3.1 × 10-4 cm² V-1 s-1. [ABSTRACT FROM AUTHOR]

Development of stretchable electronics has been driven by key applications such as electronics skin for robotic or prosthetic. Mimicking skin functionalities imposes at a minimal level: stretchability, pressure, and temperature sensing capabilities. While the research on pressure sensors for artificial skin is extensive, stretchable temperature sensors remain less explored. In this work, a stretchable temperature and infrared sensor has been developed on a polydimethylsiloxane substrate. The sensor is based on poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) as a pyroelectric material. This material is sandwiched between two electrodes. The first one consists of aluminium serpentines, covered by gold in order to get electrical contact and maximum stretchability. The second one is based on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) that has shown good electrical compatibility with PVDF-TrFE and provides the stretchability of the top electrode. Without poling the PVDF-TrFE, sensor has shown a sensitivity of around 7 pF.°C−1 up to 35% strain without any change in its behaviour. Then, taking advantage on infrared absorption of PEDOT:PSS, a poled device has shown a pyroelectric peak of 13 mV to an infrared illumination of 5 mW at 830 nm. This stretchable device valuably allows an electronic skin (e-skin) use for contact and more importantly non-contact thermal sensing.

In this paper, the studies of Molecular Single electron Transistor (MSET) is presented. We have used the Extended Huckel Theory (EHT) coupled with non-equilibrium green's function (NEGF) formalism which is implemented in ATOMISTIC TOOLKIT package. The transport properties with different electrode materials have been studied for the first time using pentacene molecule. The presence of Coulomb blockade on I–V characteristics confirmed that our device operates as Single Electron Transistor. The negative differential resistance (NDR) effect and the coulomb Staircase state has been outlined. The transmission Spectra and density of states (DOS) dependence of the electrode has also been explored to analyze the I-V curves. The NDR behavior and size device make our MSET as a good candidate for use in gate logic circuit with low consumption. [ABSTRACT FROM AUTHOR]

Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is widely used as hole injection/extraction material in organic optoelectronics. However, there still exist drawbacks for PEDOT:PSS such as low work function (WF), poor structural and electrical homogeneity. To solve these problems, methylnaphthalene sulfonate formaldehyde condensate (MNSF) is applied, which has excellent dispersion property, branched chemical structure, and low cost, as dispersant and dopant instead of linear PSS to prepare PEDOT:MNSF. The hole injection/extraction capability of PEDOT:MNSF is systematically studied in organic optoelectronic devices. PEDOT:MNSF-1:6 exhibits unexpected high device performance with a maxima current efficiency of 33.4 cd A−1 in blue phosphorescent organic light-emitting diode and a power conversion efficiency of 13.1% in CH3NH3PbI xCl3− x-based inverted perovskite solar cell, respectively. Compared with PEDOT:PSS, the relatively higher efficiency of PEDOT:MNSF-1:6 is attributed mainly to its higher WF of 5.29 eV, structural and electrical homogeneity. Our research displays a promising future of MNSF as a cheap and widely available alternative of PSS. Moreover, a clear map is provided for the design of dopant for PEDOT considering the structure of dopant. [ABSTRACT FROM AUTHOR]

The optoelectronic and electronic properties of coronene ([6]circulene) and push-pull coronene molecules were predicted by using different computational chemistry programs. For this aim, the electron/hole reorganization energies, the adiabatic/vertical ionization potentials, the adiabatic/vertical electron affinities, the chemical hardness values, the frontier orbital shapes and energy levels of the coronene and its derivatives were obtained at B3LYP/6-31G(d) level. Then the energies of the studied molecules in S 0 , S 1 , and T 1 states were calculated at PBE0/TZP level. From the obtained results, the emission values and TADF parameters of the investigated compounds were determined. Based on the theoretically obtained results, it was found that 6ethynyl-coronene and 12ethynyl-coronene molecules can be used as electron transfer materials and 6cyano-coronene and 12cyano-coronene compounds can be utilized as hole transfer materials. Additionally, it was noted that 6NO 2 -coronene and 12NH 2 -coronene derivatives can be good candidates for electron blocking materials, while 6NH 2 -coronene and 12NH 2 -coronene molecules can be utilized as hole blocking materials. Furthermore, it was emphasized that both 6NH 2 -coronene and 12NH 2 -coronene molecules can be good candidates as both electron injection and hole injection materials. Lastly, it was reported that 6ethynyl-coronene and 12cyano-coronene structures can be considered the most suitable candidates for near infrared organic emitting diodes. [Display omitted] • Coronene and push-pull substituted coronene derivatives were theoretically designed for optoelectronic applications. • The optoelectronic properties of the studied molecules were predicted using different computational chemistry tools. • From the theoretically obtained results, suitable candidate(s) were suggested for each layer in OLED devices. [ABSTRACT FROM AUTHOR]

Pentacene is an organic semiconductor used in a variety of thin-film organic electronic devices. Although at least six separate syntheses of pentacene are known (two from dihydropentacenes, two from 6,13-pentacenedione and two from 6,13-dihydro-6,13-dihydroxypentacene), none is ideal and several utilize elevated temperatures that may facilitate the oxidation of pentacene as it is produced. Here, we present a fast (~2 min of reaction time), simple, high-yielding (≥90%), low temperature synthesis of pentacene from readily available 6,13-dihydro-6,13-dihydroxypentacene. Further, we discuss the mechanism of this highly efficient reaction. With this improved synthesis, researchers gain rapid, affordable access to high purity pentacene in excellent yield and without the need for a time consuming sublimation.

The development of mobile haptics and multimodal designs has been strongly limited by the lack of enabling actuator technologies. This paper presents the properties of an electrostrive actuator technology for haptic feedback. By carefully tailoring material properties and actuator designing which can be integrating in devices, this technology should provide a realistic possibility of haptic design with considerable latitude. Haptic characteristics are described and realized and their impact on haptic design is discussed. [ABSTRACT FROM AUTHOR]

The application of organic carbonyl compounds as high performance electrode materials in secondary batteries enables access to metal-free, low-cost, environmental friendly, flexible, and functional rechargeable energy storage systems. Organic compounds have so far not received much attention as potential active materials in batteries, mainly because of the success of inorganic materials in both research and commercial applications. However, new requirements in secondary batteries such as flexibility accompanied with low production costs and environmental friendliness, in particular for portable devices, reach the limit of inorganic electrode materials. Organic carbonyl compounds represent the most promising materials to satisfy these needs. Here, recent efforts of the research in the field of organic carbonyl materials for secondary batteries are summarized, and the working principle and the structural design of different groups of carbonyl material is presented. Finally, the influence of conductive additives and binders on the cell performance is closely evaluated for each class of materials. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report our experimental design in searching a smart and easy-to-read dosimeter used to detect 6MV X-rays for improving patient safety in radiation oncology. The device was based on an organic emissive solutions of poly(2-methoxy-5(2′-ethylhexyloxy)-p-phenylenevinylene) (MEH-PPV), aluminum-tris-(8-hydroxyquinoline) (Alq3) and additive components which were characterized by UV–Vis absorption, photoluminescence and CIE color coordinate diagram. The optical properties of MEH-PPV/Alq3 solutions have been examined as function of radiation dose over the range of 0–100Gy. It has shown that MEH-PPV/Alq3 solutions are specifically sensitive to X-rays, since the effect of radiation on this organic system is strongly correlated with the efficient spectral overlap between Alq3 emission and the absorption of degraded MEH-PPV, which alters the color and photoemission of MEH-PPV/Alq3 mixtures from red to yellow, and then to green. The rate of this change is more sensitive when MEH-PPV/Alq3 is irradiated in the presence of benzoyl peroxide than when in the presence of hindered phenolic stabilizers, respectively, an accelerator and an inhibitor to activate or inhibit free radical formation. This gives rise to optimize the response curve of the dosimeter. It is clear from the experimental results that organic emissive semiconductors have potential to be used as dedicated and low-cost dosimeters to provide an independent check of beam output of a linear accelerator and therefore to give patients the opportunity to have information on the dose prescription or equipment-related problems a few minutes before being exposed to radiation. [Copyright &y& Elsevier]

Pentacene is an organic semiconductor used in a variety of thin-film organic electronic devices. Although at least six separate syntheses of pentacene are known (two from dihydropentacenes, two from 6,13-pentacenedione and two from 6,13-dihydro-6,13- dihydroxypentacene), none is ideal and several utilize elevated temperatures that may facilitate the oxidation of pentacene as it is produced. Here, we present a fast (∼2 min of reaction time), simple, high-yielding (⩾90%), low temperature synthesis of pentacene from readily available 6,13-dihydro-6,13-dihydroxypentacene. Further, we discuss the mechanism of this highly efficient reaction. With this improved synthesis, researchers gain rapid, affordable access to high purity pentacene in excellent yield and without the need for a time consuming sublimation. [ABSTRACT FROM AUTHOR]

In this work it is presented the characterization and fabrication of a novel ionizing radiation detector for high energy photon beam (6.0 MV). It is used organic luminescent materials usually applied in light-emitting and nanostructure device, but still few explored in radiation dosimetry. Organic solutions of tris(8-hydroxyquinolinato) aluminum - Alq3 and poly[2-methoxy-5-(2′-ethylhexyloxy)-p-phenylene vinylene] - MEH-PPV were prepared to better study the impact of spectral overlap between the Alq3 emission and MEH-PPV absorption. It is observed a blue-shift on the photoluminescence of the MEH-PPV/Alq3 solution system from red-orange (λmax = 598 nm) to green (λmax = 545 nm) when the radiation dose changes from 0 to 100 Gy. This effect is attributed to the photoxidation process of MEH-PPV and was employed to design dose accumulation detector in order to represent easily the radiation dose for cancer treatment. [ABSTRACT FROM AUTHOR]