Asit Kar - Academia.edu (original) (raw)

Papers by Asit Kar

Nanotechnology

This article addresses the synthesis of Fe3+ doped TiO2 nanoparticles with variations of molar co... more This article addresses the synthesis of Fe3+ doped TiO2 nanoparticles with variations of molar concentrations of Fe3+ and their adequate use as potential photocatalysts for Photocatalysis applications. Synthesized photocatalysts were characterized thoroughly by different analytical techniques in terms of morphological, chemical, structural, crystalline, optical, electronic structure, surface area etc properties. The occurrence of red shift phenomenon of the energy band gap attributes to the transfer of charges and transition between the d electrons of dopant and conduction band (CB) or valence band (VB) of TiO2. The doping of Fe3+ ions generates more trap sites for charge carriers with the surface trap sites. Thorough experimental conclusions revealed that the Fe3+ ions necessarily regulate the catalytic property of TiO2 nanomaterial. The obtained total degradation efficiency rate of Methylene Blue (MB) was 93.3% in the presence of 0.1 M Fe3+ in the host material and for Malachite G...

Ceramics International, May 1, 2023

Journal of Photochemistry and Photobiology A-chemistry, Mar 1, 2023

New Journal of Chemistry, 2023

Excitation wavelength-dependent visible emissions from ZnO nanostructures demonstrate that defect... more Excitation wavelength-dependent visible emissions from ZnO nanostructures demonstrate that defect states are insufficient to explain their optical properties.

SOLID STATE PHYSICS: Proceedings of the 58th DAE Solid State Physics Symposium 2013, 2014

ABSTRACT Flower-like ZnO nanostructure of novel morphologies has been fabricated by a simple wet ... more ABSTRACT Flower-like ZnO nanostructure of novel morphologies has been fabricated by a simple wet colloid chemical method. A two-step wet chemical process has been used to prepare ZnO nanoflower on glass substrates using zinc acetate dihydrate [Zn(CH3COO)2̇2H2O] at room temperature. Growth structure of the nanoflowers has been investigated by SEM. UV-Vis absorption spectrum shows an absorption band at 355 nm due to nanosize ZnO. Photoluminescence spectrum exhibits two emission peaks - one at 351 nm corresponding to band gap excitonic emission and another located at 470 nm due to the presence of ionized oxygen vacancies.

Surface Science, Jul 1, 2002

Atomically ordered array of Cu atoms on the Cu(1 0 0) surface was observed by a scanning tunnelin... more Atomically ordered array of Cu atoms on the Cu(1 0 0) surface was observed by a scanning tunneling microscope (STM) in ultrahigh vacuum (UHV) at room temperature. STM-induced photon emission spectra from the Cu(1 0 0) surface were investigated by a photon detection system combined with the UHV-STM. The starting bias voltage of the detectable photon emission is 2.2 V. The spectrum shape is dominated by the imaginary part of the dielectric function of copper and exhibits a characteristic peak around 2.0 eV. The emission intensity increases almost linearly with tunneling currents but not monotoniously with bias voltages. No apparent bias-polarity dependence in the emission spectra was found. The spectral features are interpreted on the basis of the radiative decay of localized plamons excited by inelastic tunneling electrons.

Thin Solid Films, Aug 1, 2003

Using epitaxially grown graphene on Ru(0001) as a decoupling layer, we investigate the evolution ... more Using epitaxially grown graphene on Ru(0001) as a decoupling layer, we investigate the evolution of tunneling electron induced luminescence from different number of layers of porphyrin molecules. Light emission spectra and photon maps, acquired via a combined optical setup with scanning tunneling microscopy (STM), indicate that the electronic decoupling effect of a monolayer (ML) graphene alone is still insufficient for generating molecule-specific emission from both the 1st-and 2nd-layer porphyrin molecules. Nevertheless, interestingly, the plasmonic emission is enhanced for the 1st-layer but suppressed for the 2nd-layer in comparison with the plasmonic emission on the monolayer graphene. Intrinsic intramolecular molecular fluorescence occurs at the 3rd-layer porphyrin. Such molecular thickness is about two MLs thinner than previous reports where molecules were adsorbed directly on metals. These observations suggest that the monolayer graphene does weaken the interaction between molecule and metal substrate and contribute to the reduction of nonradiative decay rates.

Materials Science in Semiconductor Processing, 2020

PAni-TiO 2 nanocomposite was prepared by ex-situ oxidative chemical polymerization method. Hydrot... more PAni-TiO 2 nanocomposite was prepared by ex-situ oxidative chemical polymerization method. Hydrothermally prepared TiO 2 nanoparticles were mixed with PAni (polyaniline) where two different percentage amount of TiO 2 , viz. 20% and 40% were used during the polymerization reaction. Broad peak around 240 nm in UV-Vis absorption spectra implies the absorbance of TiO 2 in nanocomposite in UV region. XRD, TEM, SAED and HRTEM analysis confirms crystalline nature of PAni and PAni-TiO 2 nanocomposite. In the composite, TiO 2 remains like an amorphous material. FESEM analysis shows a strong effect of TiO 2 on the morphology of PAni. PAni exhibits agglomerated nanoparticles while nanoflake, nanorod and nanowire like morphology are observed after composite formation with TiO 2. XPS analysis confirms the presence of expected elements in the materials. Photoluminescence emission spectra of the PAni-TiO 2 , acquired in the range of 300 nm-700 nm, show that the emission intensity is quenched with increasing TiO 2 amount in the composite. The broad peak around 400 nm is attributed to the radiative annihilation of excitons. A peak appearing between 450 nm and 500 nm of the composites is assigned to the bandgap recombination of electron-hole pairs. The photocatalytic dye degradation rate of the composite is increased with increase in TiO 2 content. For highest content of TiO 2 in PAni matrix, photocatalytic dye degradation rate is increased nearly by 100% with respect to pristine PAni.

ECS Journal of Solid State Science and Technology, Aug 1, 2022

Materials research express, Jul 3, 2019

World Academy of Science, Engineering and Technology, International Journal of Chemical and Molecular Engineering, Aug 17, 2015

Physical Chemistry Chemical Physics, 2022

A complementary role of photophysical processes and defect states in surface-modified ZnO nanopar... more A complementary role of photophysical processes and defect states in surface-modified ZnO nanoparticles for photocatalysis and HyLED applications.

Materials Letters, Nov 1, 2021

Abstract Surface modification of the ZnO nanoparticles using polymer can be an important way to t... more Abstract Surface modification of the ZnO nanoparticles using polymer can be an important way to tune their optoelectronic properties. On capping the ZnO nanoparticles (NPs) using the polymer polyvinylpyrrolidone (PVP), a synchronous change in the photoluminescence emission has been observed from different defect states with different formation energies, which raises doubts about the decade-old proposed theory of passivation of defect states upon surface capping. The doubt has been confirmed by X-ray photoelectron spectroscopy (XPS) of the samples. Blue shifting of the band edge absorption on polymer capping has been attributed to a change in exciton dynamics due to the tuning of band alignment on surface modification. Polymer concentration-dependent tunability for emission from defect states has been explored using two new photophysical process – acceptor (PVP)-concentration-dependent Forster resonance energy transfer (FRET), and generation of superoxide ( O 2 - ) charge-transfer states. Surface capping has been found to improve spectral purity at the cost of a decrease in quantum efficiency. Therefore, to design a very bright hybrid light-emitting layer using polymer capped ZnO, we must consider the emission and absorption spectral overlap between the ZnO nanoparticles and the polymer, FRET, exciton diffusion and balling efficiency of the polymer.

Materials research express, Jul 26, 2019

Journal of Materials Science: Materials in Electronics, 2021

Luminescent polypyrrole–polymethylmethacrylate (PPy–PMMA) blends have been obtained by bulk polym... more Luminescent polypyrrole–polymethylmethacrylate (PPy–PMMA) blends have been obtained by bulk polymerization of MMA in presence of different concentration of PPy nanowires. The PPy nanowires are distributed over the rock-like features of PMMA as observed from SEM images. Raman spectra indicate the formation of blend. PPy–PMMA blends exhibit high photoluminescence emission intensity though PPy is not a fluorescent polymer. All the blends exhibit blue emission as observed in CIE diagram. Enhanced emission from the blend as compared to pristine PPy is obtained due to Forster resonance energy transfer (FRET) between PMMA and PPy. The emission intensity of the blend becomes highest for an optimized amount of both the components, i.e. 0.8 g of PPy to 1 ml of MMA in the blend with energy transfer efficiency of 66% and high colour purity. So, optimization of the amount of PPy and PMMA in the blend is important to get high luminescence from the PPy–PMMA blend. The maximum electroluminescence quantum efficiency of the polymer light-emitting diode (PLED) using optimized PPy–PMMA blend as active layer is found to be 2% at turn on voltage of 3 V for the emission at wavelength of 400 nm, whereas at turn on voltage of 3.5 V, the PLED emits light of wavelength 330 nm.

Journal of Environmental Chemical Engineering, 2020

3RD INTERNATIONAL CONFERENCE ON CONDENSED MATTER AND APPLIED PHYSICS (ICC-2019), 2020

AIP Conference Proceedings, 2020

ZnO is a wide bandgap, n-type semiconductor and it is much popular for many applications like pho... more ZnO is a wide bandgap, n-type semiconductor and it is much popular for many applications like photodiode, sensors, solar cell, LEDs etc. There are many methods for the synthesis of ZnO, among all of them co-precipitation method is a very simple method. In this present work, we synthesized ZnO and Cu doped ZnO at particular wt% (5wt%) and then study its morphological, optical properties and finally demonstrated for degradation of MO dye using visible light. The ZnO and Cu doped ZnO nanoparticles were characterized by FTIR, SEM, Photoluminescence and UV-VIS spectroscopy. FTIR spectra reveal the presence of Zn-O bond and Metal-O bond. Pure ZnO sample shows plate-like structure and Cu doped ZnO shows a layered sheet-like structure which is settled on top of one another. UV-VIS spectroscopy shows a peak at 369 nm for pure ZnO and it is slightly blue-shifted (362 nm) for Cu doped ZnO. PL spectroscopy reveals quenching in UV region and enhancement in visible region after doping which confirms the degradation efficiency in visible region. Finally, photodegradation of MO dye is performed and Cu doped ZnO shows much higher efficiency (50 %) than pure ZnO (24.72 %).

Materials Today: Proceedings, 2019

Among the conducting polymers, polypyrrole (PPY) has drawn a lot of interest due to its excellent... more Among the conducting polymers, polypyrrole (PPY) has drawn a lot of interest due to its excellent environmental stability, ease of preparation and high conductivity. Here we have used chemical oxidative polymerization to synthesize PPY from its monomer pyrrole. We have studied morphological and optical properties of PPY samples by varying the monomer to oxidant molar ratio as 1:1.25 and 1:2 and denoted the samples by 1125ppy and 1200ppy respectively. The prepared samples are characterized by FTIR, UV-Vis, photoluminescence (PL) spectroscopy and FESEM. FTIR spectra reveal the required functional groups that should be present in PPY. From UV-Vis spectra, it is clear that the band gap of PPY changes due to the variation of monomer to oxidant ratio. There are two major absorption bands among which one is at about 350 nm for both the samples due to π-π* transition and another absorption band is at about 600nm for 1125ppy due to polaron band transition. The polaron band transition for 1200ppy is observed at about 650 nm. This redshift is due to the increased extent of oxidation induced by increasing the amount of oxidant. From the FESEM image, it is observed that agglomeration of particles increases with thedecreased monomer to oxidant ratio. As the ratio decreases the rate of oxidation increases and more cross-linked structure of polypyrrole is formed which resultsin more agglomerated structure. PL Spectra shows that 1125ppy has higher PL intensity than that of 1200ppy. Since agglomeration quenches PL intensity, the process is supported by our SEM results. So, PL intensity decreases with decreasing monomer to oxidant ratio.

Materials Science in Semiconductor Processing, 2019

Polypyrrole-PMMA (PPy-PMMA) blends have been prepared by chemical oxidative polymerization method... more Polypyrrole-PMMA (PPy-PMMA) blends have been prepared by chemical oxidative polymerization method. The band gap of all the blends lies in semiconductive range though PMMA is insulating in nature. Spherical agglomerated structure of the blends is observed from microstructural images. High photoluminescence (PL) intensity is obtained in PPy-PMMA blends even if PPy has low PL emission efficiency. The enhancement of PL emission intensity of the blends is due to Forster resonance energy transfer. Here an energy transfer occurs from donor PMMA to acceptor PPy which enhances the emission intensity of PPy. PL spectra show the increase in emission intensity with increase in concentration of PMMA in the blend up to a certain limit. Donor-donor interaction is also observed in the blend due to which the emission intensity of the blend having excess amount of PMMA suddenly falls down. Thus by tuning the amount of PMMA added in PPy matrix the PL intensity of the blend can be tuned and the blend can be used as a promising material for optoelectronic devices.

Nanotechnology

This article addresses the synthesis of Fe3+ doped TiO2 nanoparticles with variations of molar co... more This article addresses the synthesis of Fe3+ doped TiO2 nanoparticles with variations of molar concentrations of Fe3+ and their adequate use as potential photocatalysts for Photocatalysis applications. Synthesized photocatalysts were characterized thoroughly by different analytical techniques in terms of morphological, chemical, structural, crystalline, optical, electronic structure, surface area etc properties. The occurrence of red shift phenomenon of the energy band gap attributes to the transfer of charges and transition between the d electrons of dopant and conduction band (CB) or valence band (VB) of TiO2. The doping of Fe3+ ions generates more trap sites for charge carriers with the surface trap sites. Thorough experimental conclusions revealed that the Fe3+ ions necessarily regulate the catalytic property of TiO2 nanomaterial. The obtained total degradation efficiency rate of Methylene Blue (MB) was 93.3% in the presence of 0.1 M Fe3+ in the host material and for Malachite G...

Ceramics International, May 1, 2023

Journal of Photochemistry and Photobiology A-chemistry, Mar 1, 2023

New Journal of Chemistry, 2023

Excitation wavelength-dependent visible emissions from ZnO nanostructures demonstrate that defect... more Excitation wavelength-dependent visible emissions from ZnO nanostructures demonstrate that defect states are insufficient to explain their optical properties.

SOLID STATE PHYSICS: Proceedings of the 58th DAE Solid State Physics Symposium 2013, 2014

ABSTRACT Flower-like ZnO nanostructure of novel morphologies has been fabricated by a simple wet ... more ABSTRACT Flower-like ZnO nanostructure of novel morphologies has been fabricated by a simple wet colloid chemical method. A two-step wet chemical process has been used to prepare ZnO nanoflower on glass substrates using zinc acetate dihydrate [Zn(CH3COO)2̇2H2O] at room temperature. Growth structure of the nanoflowers has been investigated by SEM. UV-Vis absorption spectrum shows an absorption band at 355 nm due to nanosize ZnO. Photoluminescence spectrum exhibits two emission peaks - one at 351 nm corresponding to band gap excitonic emission and another located at 470 nm due to the presence of ionized oxygen vacancies.

Surface Science, Jul 1, 2002

Atomically ordered array of Cu atoms on the Cu(1 0 0) surface was observed by a scanning tunnelin... more Atomically ordered array of Cu atoms on the Cu(1 0 0) surface was observed by a scanning tunneling microscope (STM) in ultrahigh vacuum (UHV) at room temperature. STM-induced photon emission spectra from the Cu(1 0 0) surface were investigated by a photon detection system combined with the UHV-STM. The starting bias voltage of the detectable photon emission is 2.2 V. The spectrum shape is dominated by the imaginary part of the dielectric function of copper and exhibits a characteristic peak around 2.0 eV. The emission intensity increases almost linearly with tunneling currents but not monotoniously with bias voltages. No apparent bias-polarity dependence in the emission spectra was found. The spectral features are interpreted on the basis of the radiative decay of localized plamons excited by inelastic tunneling electrons.

Thin Solid Films, Aug 1, 2003

Using epitaxially grown graphene on Ru(0001) as a decoupling layer, we investigate the evolution ... more Using epitaxially grown graphene on Ru(0001) as a decoupling layer, we investigate the evolution of tunneling electron induced luminescence from different number of layers of porphyrin molecules. Light emission spectra and photon maps, acquired via a combined optical setup with scanning tunneling microscopy (STM), indicate that the electronic decoupling effect of a monolayer (ML) graphene alone is still insufficient for generating molecule-specific emission from both the 1st-and 2nd-layer porphyrin molecules. Nevertheless, interestingly, the plasmonic emission is enhanced for the 1st-layer but suppressed for the 2nd-layer in comparison with the plasmonic emission on the monolayer graphene. Intrinsic intramolecular molecular fluorescence occurs at the 3rd-layer porphyrin. Such molecular thickness is about two MLs thinner than previous reports where molecules were adsorbed directly on metals. These observations suggest that the monolayer graphene does weaken the interaction between molecule and metal substrate and contribute to the reduction of nonradiative decay rates.

Materials Science in Semiconductor Processing, 2020

PAni-TiO 2 nanocomposite was prepared by ex-situ oxidative chemical polymerization method. Hydrot... more PAni-TiO 2 nanocomposite was prepared by ex-situ oxidative chemical polymerization method. Hydrothermally prepared TiO 2 nanoparticles were mixed with PAni (polyaniline) where two different percentage amount of TiO 2 , viz. 20% and 40% were used during the polymerization reaction. Broad peak around 240 nm in UV-Vis absorption spectra implies the absorbance of TiO 2 in nanocomposite in UV region. XRD, TEM, SAED and HRTEM analysis confirms crystalline nature of PAni and PAni-TiO 2 nanocomposite. In the composite, TiO 2 remains like an amorphous material. FESEM analysis shows a strong effect of TiO 2 on the morphology of PAni. PAni exhibits agglomerated nanoparticles while nanoflake, nanorod and nanowire like morphology are observed after composite formation with TiO 2. XPS analysis confirms the presence of expected elements in the materials. Photoluminescence emission spectra of the PAni-TiO 2 , acquired in the range of 300 nm-700 nm, show that the emission intensity is quenched with increasing TiO 2 amount in the composite. The broad peak around 400 nm is attributed to the radiative annihilation of excitons. A peak appearing between 450 nm and 500 nm of the composites is assigned to the bandgap recombination of electron-hole pairs. The photocatalytic dye degradation rate of the composite is increased with increase in TiO 2 content. For highest content of TiO 2 in PAni matrix, photocatalytic dye degradation rate is increased nearly by 100% with respect to pristine PAni.

ECS Journal of Solid State Science and Technology, Aug 1, 2022

Materials research express, Jul 3, 2019

World Academy of Science, Engineering and Technology, International Journal of Chemical and Molecular Engineering, Aug 17, 2015

Physical Chemistry Chemical Physics, 2022

A complementary role of photophysical processes and defect states in surface-modified ZnO nanopar... more A complementary role of photophysical processes and defect states in surface-modified ZnO nanoparticles for photocatalysis and HyLED applications.

Materials Letters, Nov 1, 2021

Abstract Surface modification of the ZnO nanoparticles using polymer can be an important way to t... more Abstract Surface modification of the ZnO nanoparticles using polymer can be an important way to tune their optoelectronic properties. On capping the ZnO nanoparticles (NPs) using the polymer polyvinylpyrrolidone (PVP), a synchronous change in the photoluminescence emission has been observed from different defect states with different formation energies, which raises doubts about the decade-old proposed theory of passivation of defect states upon surface capping. The doubt has been confirmed by X-ray photoelectron spectroscopy (XPS) of the samples. Blue shifting of the band edge absorption on polymer capping has been attributed to a change in exciton dynamics due to the tuning of band alignment on surface modification. Polymer concentration-dependent tunability for emission from defect states has been explored using two new photophysical process – acceptor (PVP)-concentration-dependent Forster resonance energy transfer (FRET), and generation of superoxide ( O 2 - ) charge-transfer states. Surface capping has been found to improve spectral purity at the cost of a decrease in quantum efficiency. Therefore, to design a very bright hybrid light-emitting layer using polymer capped ZnO, we must consider the emission and absorption spectral overlap between the ZnO nanoparticles and the polymer, FRET, exciton diffusion and balling efficiency of the polymer.

Materials research express, Jul 26, 2019

Journal of Materials Science: Materials in Electronics, 2021

Luminescent polypyrrole–polymethylmethacrylate (PPy–PMMA) blends have been obtained by bulk polym... more Luminescent polypyrrole–polymethylmethacrylate (PPy–PMMA) blends have been obtained by bulk polymerization of MMA in presence of different concentration of PPy nanowires. The PPy nanowires are distributed over the rock-like features of PMMA as observed from SEM images. Raman spectra indicate the formation of blend. PPy–PMMA blends exhibit high photoluminescence emission intensity though PPy is not a fluorescent polymer. All the blends exhibit blue emission as observed in CIE diagram. Enhanced emission from the blend as compared to pristine PPy is obtained due to Forster resonance energy transfer (FRET) between PMMA and PPy. The emission intensity of the blend becomes highest for an optimized amount of both the components, i.e. 0.8 g of PPy to 1 ml of MMA in the blend with energy transfer efficiency of 66% and high colour purity. So, optimization of the amount of PPy and PMMA in the blend is important to get high luminescence from the PPy–PMMA blend. The maximum electroluminescence quantum efficiency of the polymer light-emitting diode (PLED) using optimized PPy–PMMA blend as active layer is found to be 2% at turn on voltage of 3 V for the emission at wavelength of 400 nm, whereas at turn on voltage of 3.5 V, the PLED emits light of wavelength 330 nm.

Journal of Environmental Chemical Engineering, 2020

3RD INTERNATIONAL CONFERENCE ON CONDENSED MATTER AND APPLIED PHYSICS (ICC-2019), 2020

AIP Conference Proceedings, 2020

ZnO is a wide bandgap, n-type semiconductor and it is much popular for many applications like pho... more ZnO is a wide bandgap, n-type semiconductor and it is much popular for many applications like photodiode, sensors, solar cell, LEDs etc. There are many methods for the synthesis of ZnO, among all of them co-precipitation method is a very simple method. In this present work, we synthesized ZnO and Cu doped ZnO at particular wt% (5wt%) and then study its morphological, optical properties and finally demonstrated for degradation of MO dye using visible light. The ZnO and Cu doped ZnO nanoparticles were characterized by FTIR, SEM, Photoluminescence and UV-VIS spectroscopy. FTIR spectra reveal the presence of Zn-O bond and Metal-O bond. Pure ZnO sample shows plate-like structure and Cu doped ZnO shows a layered sheet-like structure which is settled on top of one another. UV-VIS spectroscopy shows a peak at 369 nm for pure ZnO and it is slightly blue-shifted (362 nm) for Cu doped ZnO. PL spectroscopy reveals quenching in UV region and enhancement in visible region after doping which confirms the degradation efficiency in visible region. Finally, photodegradation of MO dye is performed and Cu doped ZnO shows much higher efficiency (50 %) than pure ZnO (24.72 %).

Materials Today: Proceedings, 2019

Among the conducting polymers, polypyrrole (PPY) has drawn a lot of interest due to its excellent... more Among the conducting polymers, polypyrrole (PPY) has drawn a lot of interest due to its excellent environmental stability, ease of preparation and high conductivity. Here we have used chemical oxidative polymerization to synthesize PPY from its monomer pyrrole. We have studied morphological and optical properties of PPY samples by varying the monomer to oxidant molar ratio as 1:1.25 and 1:2 and denoted the samples by 1125ppy and 1200ppy respectively. The prepared samples are characterized by FTIR, UV-Vis, photoluminescence (PL) spectroscopy and FESEM. FTIR spectra reveal the required functional groups that should be present in PPY. From UV-Vis spectra, it is clear that the band gap of PPY changes due to the variation of monomer to oxidant ratio. There are two major absorption bands among which one is at about 350 nm for both the samples due to π-π* transition and another absorption band is at about 600nm for 1125ppy due to polaron band transition. The polaron band transition for 1200ppy is observed at about 650 nm. This redshift is due to the increased extent of oxidation induced by increasing the amount of oxidant. From the FESEM image, it is observed that agglomeration of particles increases with thedecreased monomer to oxidant ratio. As the ratio decreases the rate of oxidation increases and more cross-linked structure of polypyrrole is formed which resultsin more agglomerated structure. PL Spectra shows that 1125ppy has higher PL intensity than that of 1200ppy. Since agglomeration quenches PL intensity, the process is supported by our SEM results. So, PL intensity decreases with decreasing monomer to oxidant ratio.

Materials Science in Semiconductor Processing, 2019

Polypyrrole-PMMA (PPy-PMMA) blends have been prepared by chemical oxidative polymerization method... more Polypyrrole-PMMA (PPy-PMMA) blends have been prepared by chemical oxidative polymerization method. The band gap of all the blends lies in semiconductive range though PMMA is insulating in nature. Spherical agglomerated structure of the blends is observed from microstructural images. High photoluminescence (PL) intensity is obtained in PPy-PMMA blends even if PPy has low PL emission efficiency. The enhancement of PL emission intensity of the blends is due to Forster resonance energy transfer. Here an energy transfer occurs from donor PMMA to acceptor PPy which enhances the emission intensity of PPy. PL spectra show the increase in emission intensity with increase in concentration of PMMA in the blend up to a certain limit. Donor-donor interaction is also observed in the blend due to which the emission intensity of the blend having excess amount of PMMA suddenly falls down. Thus by tuning the amount of PMMA added in PPy matrix the PL intensity of the blend can be tuned and the blend can be used as a promising material for optoelectronic devices.