Application In Hybrid Solar Cells Research Articles

Surface modification of CBD-grown CdS thin films for hybrid solar cell applications

The influences of interfacial modification by various dyes (Eosin-Y, D205, N719 and N3) on structural, morphological, optical and electrical properties of CdS-based hybrid solar cells are investigated. Structural properties showed the cubic growth of chemical bath deposited CdS thin films. Morphological analysis indicated that CdS specimen had a smooth and crack-free surface whereas P3HT layer coated on CdS thin films displayed spherical grains with nonuniform distribution. According to Tauc’s estimation conclusions, CdS and P3HT layers exhibited band gaps of 2.98 eV and 1.98 eV, respectively. The surface modification of CdS thin films by diverse dyes led to an increase in the absorption spectra of the CdS samples. Photoluminescence data showed that surface treatment of CdS samples by diverse dyes caused a decrease in the luminescence intensity of the CdS-based hybrid solar cells, meaning that efficient exciton dissociation was obtained. All the devices showed an obvious photovoltaic effect as a result of current density-voltage (J–V) curves. Furthermore, the highest solar cell efficiency was achieved for ITO/CdS/N3/Ag device as 0.322%, which could be ascribed to the surface modification of CdS thin films, giving rise to a formation of better interface between CdS and P3HT layers.

Hot injection synthesis of CuInS2 nanocrystals using metal xanthates and their application in hybrid solar cells

Copper indium sulfide nanocrystals with sizes of 3–4 nm were synthesized from metal xanthates in a hot injection reaction. After ligand exchange, their performance as acceptors in polymer/nanocrystal hybrid solar cells was evaluated.

Conjugated materials containing dithieno[3,2-b:2′,3′-d]pyrrole and its derivatives for organic and hybrid solar cell applications

Dithieno[3,2-b:2′,3′-d]pyrrole (DTP) and its derivatives have occupied an important position in both electron-rich and electron-deficient building blocks to construct photovoltaic materials. Here, we highlight the exciting progress of donors based on original DTP,N-acyl DTP and fused DTP and acceptors based on lactam and imide, respectively.

Iron and nickel doped tin (IV) oxide nanosheets: Synthesis, characterization and applications in hybrid solar cells

The pristine and (Fe and Ni)-doped tin (IV) oxide (SnO2) nanosheets were synthesized by hydrothermal method. These nanosheets were characterized in detail by UV- visible spectroscopy, fourier transform infra-red (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). TEM revealed that the nanosheets varied in size from 14 nm to 40 nm. Electrical parameters such as resistance, resistivity and conductivity were also investigated by two probe resistivity measurements. Doped SnO2 nanosheets were found more conducting than pristine SnO2. The pristine and (Fe and Ni)-doped SnO2 nanosheets were used to fabricate photoactive blend for solid state dye-sensitized solar cells (DSSCs). The effects of pristine and (Fe and Ni)-doped SnO2 nanosheets on the efficiency of solar cells were investigated using photocurrent-voltage (J-V) measurements. Maximum power conversion efficiency of 0.48% was recorded for Ni-doped SnO2 nanosheets grafted with sulphonic acid functionalized dye. Other characteristic photovoltaic parameters were found as 2.54 mAcm−2, short circuit current density (Jsc), 0.42 mV, open circuit voltage (Voc) and 0.45, fill factor (FF). The band gap of SnO2 (3.8 eV) was significantly reduced to 3.2 eV and 2.8 eV for Fe and Ni-doped SnO2 respectively.

ZnO nanoparticles and polyaniline blend as an active layer for bulk heterojunction solar cell applications

In this work, a facile and straightforward procedure was introduced to prepare a blend as an active layer for hybrid solar cell applications. The active layer consisting of a blend of ZnO nanoparticles (NPs) and polyaniline (PANI) dispersions was deposited by spin coating on ITO covered glasses. The current density–voltage characteristics were studied under AM1.5G standard illumination, without any encapsulation process. Also, the samples were studied using UV–Vis spectroscopy, energy dispersive X-ray spectroscopy (EDS) and field emission-scanning electron microscopy. The investigation is limited just to the active layer, so the cells were fabricated without any interlayer. The effect of various volume ratios of ZnO–NPs:PANI solutions, thickness and the annealing temperature of the active layer on the open circuit voltage and the short circuit current density of the cells were investigated. Moreover, the blending time of ZnO–NPs:PANI dispersions as a significant factor for achieving the optimum results were studied.

Effect of localized surface plasmon resonance from incorporated gold nanoparticles in PEDOT:PSS hole transport layer for hybrid solar cell applications

We report optical and structural properties of poly (3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) incorporated gold nanoparticles capped by citrates (Au-citrates) as hole transport layer for hybrid organic-inorganic solar cell applications. PEDOT:PSS and Au-citrates both are water solution and the mixed are done in 2.378 wt%, 2.978 wt% and 3.144 wt% of Au-citrates. Plasmonic peak in the wavelength area of ∼525 nm for Au-citrates is found quite stable after addition of iso-propanol for wettability purpose. In our result, enhanced absorbance spectra of PEDOT:PSS incorporated Au-citrates indicates the effect of localized surface plasmon resonance from Au-citrates and it is estimated to enhance performance of hybrid solar cell efficiency. Optical properties of the thin films in hybrid solar cell device are done in the structure of ITO/ZnO/P3HT:PCBM(active layer)/(PEDOT:PSS:Au-citrates). The complete layer structure shows the enhancement of optical property in all UV-vis region in comparison to that structure without Au-citrates.

Investigation of annealing effects on TiO2 nanotubes synthesized by a hydrothermal method for hybrid solar cells

In this work, we have synthesized titanium dioxide nanotubes using the hydrothermal method. The obtained nanotubes were annealed at 400 °C and 600 °C to investigate the effect of annealing on the crystallinity of nanotubes. The synthesized nanotubes were then sensitized by a conducting polymer poly [2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEHPPV) in order to compose an improved donor: acceptor system for hybrid solar cell application. To elucidate the formation of nanotubes and then their corresponding polymer nanocomposites, morphological studies were done using high-resolution transmission electron microscopy. The absorbance properties of modified TiO2 nanotubes in the polymer matrix of MEHPPV were investigated by UV–Vis absorption spectra. Furthermore, the charge transfer properties were studied by ensuing quenching effect in as-synthesized polymer nanocomposites. The extension of the study involved utilization of these polymer nanocomposites in solar cells that involved a comparative study of the hybrid nanocomposites based solar cells and obtaining their I–V characteristics in order to realize the fabrication of an efficient photovoltaic device.

The study of colloidal lead bromide perovskite nanocrystals and its application in hybrid solar cells

In this study, we investigated inorganic cesium lead halide perovskite semiconductor and tested its application in photovoltaics. Highly crystalline material was synthesized by two different approaches, including a high temperature route and a low temperature method. Inorganic-polymer hybrid solar cells based on solution-deposited layers of CsPbBr3 nanocrystals were successfully fabricated in ambient, with and without post treatments. The solar cells employing nanocrystals with short ligands, obtained from low temperature route, outperformed the devices with long ligands. The devices exhibited an efficiency up to 1.16%, with an open circuit voltage (Voc) of 0.87 V, a fill factor of 56.2% and a short-circuit current density (Jsc) of 2.38 mA/cm2.

Impact of the titania nanostructure on charge transport and its application in hybrid solar cells

Porous titania films are widely studied in a number of optoelectronic applications due to its favorable optical and electronic characteristics. Mesoporous titania thin films (MTTFs) with tunable pore size, pore order, accessibility and crystallinity are of interest in electronic devices due to the potential for optimization of the desired characteristics for charge separation and carrier transport. In this work, several MTTFs were prepared by sol–gel chemistry with different structural properties tuned by post-synthesis thermal treatment. The effect of the structural properties (pore diameter, order and accessibility) on the electrical properties of the material was studied by films fabrication onto a transparent conducting electrode, ITO, such that it enables optoelectronic applications. The performance as photoanode was explored by the fabrication of hybrid polymer (P3HT): titania solar cells. Not only does structural properties affect polymer impregnation inside the titania pores as expected and hence impacts charge separation at the interface, but also the thermal treatment affects crystallinity and the films electronic properties. A more complete picture about the electronic properties of the different MTTFs prepared in this work was studied by mobility measurement by space charge limited current and impedance spectroscopy.

Delocalization of π electrons and trapping action of ZnO nanoparticles in PPY matrix for hybrid solar cell application

Polypyrrole (PPY)-Zinc Oxide (ZnO) nanocomposites with varying concentration of ZnO (1:1–1:4) were prepared via in-situ polymerization technique by using pyrrole monomer in the presence of ammonium persulphate (APS) as oxidant. Globular morphology of PPY and sheet like structure of ZnO was examined using FESEM and EDAX. FTIR showed the presence of vibration modes in fingerprint region (1500 cm−1–500 cm−1) for metal oxides confirming the presence and interaction of ZnO with the polymer matrix in nanocomposites. Amorphous nature of PPY and hexagonal wurtzite structure of ZnO was confirmed using XRD with average crystallite size within 20 nm–30 nm. PANI-ZnO (1:1) exhibited blue shift in comparison to PPY (neat) and optimized optical band gap ∼ 1.81 eV. The effect of carrier concentration was investigated using electrochemical analyzer and maximum current was recorded for PANI-ZnO (1:1). The highest conductance was calculated for PANI-ZnO (1:1) ∼ 7.3242 × 10−3 S using current –voltage characteristics. Thermal stability was found to be increasing with the increase in ZnO concentration PANI-ZnO nanocomposite.

Synthesis of graphene oxide/poly(3,4–ethylenedioxythiophene) composites by Fenton's reagent

Graphene oxide/poly(3,4–ethylenedioxythiophene) composites were synthesized through Fenton's reaction. The synthesis was performed using graphene oxide intercalated with iron (III) chloride and hydrogen peroxide. Then, in situ polymerization of 3,4–ethylenedioxythiophene monomer via Fenton's reaction on graphene oxide was accomplished. The composites exhibit a matrix growth of poly(3,4–ethylenedioxythiophene) chains on and around the graphene oxide layers presenting π−π interactions between both materials. The electroactivity and optical properties of the composite were increased. The intercalation of iron (III) chloride is demonstrated through X–ray diffraction as the interlayer distance of the graphene oxide sheets increased with the addition of the compound. Transmission electron microscopy analysis was carried out to establish that the polymer matrix was growing around the layers. The Fourier transform infrared spectroscopy measurements were implemented as a complementary technique for Raman to confirm the possibility of a π–π interaction. The materials show a maximum fluorescence emission at 480 and 530 nm. Properties were measured to establish the presumable application in hybrid solar cells, due to the absorption of the composite in the UV and near–IR region in a range of 210–350 nm and 700–800 nm. The composites exhibited a matrix growth of conducting polymer chains on and around the graphene oxide layers presenting red–ox states with a potential application as a counter electrode.

Study on Production of Silicon Nanoparticles from Quartz Sand for Hybrid Solar Cell Applications

Nano silicon (nano Si) particles were directly prepared from natural mineral quartz sand and thereafter used to fabricate the hybrid silicon solar cells. Here, in this preparation technique, two process stages were involved. In the first stage, the alkaline extraction and acid precipitation processes were applied on quartz sand to fetch silica nanoparticles. In the second stage, magnesiothermic and modified magnesiothermic reduction reactions were applied on nano silica particles to prepare nano Si particles. The effect of two distinct reduction methodologies on nano Si particle preparation was compared. The magnesiothermic and modified magnesiothermic reductions in the silica to silicon conversion process were studied with the help of x-ray diffraction (XRD) with intent to study the phase changes during the reduction reaction as well as its crystalline nature in the pure silicon phase. The particles consist of a combination of fine particles with spherical morphology. In addition to this, the optical study indicated an increase in visible light absorption and also increases the performance of the solar cell. The obtained nano Si particles were used as an active layer to fabricate the hybrid solar cells (HSCs). The obtained results confirmed that the power conversion efficiency (PCE) of the magnesiothermically modified nano Si cells (1.06%) is much higher as compared to the nano Si cells that underwent magnesiothermic reduction (1.02%). Thus, this confirms the increased PCE of the investigated nano Si solar cell up to 1.06%. It also revealed that nano Si behaved as an electron acceptor and transport material. The present study provided valuable insights and direction for the preparation of nano Si particles from quartz sand, including the influence of process methods. The prepared nano Si particles can be utilized for HSCs and an array of portable electronic devices.

Studies on ternary zinc blend based semiconducting quantum dots for hybrid solar cell applications

A systematic study is presented in the present work on the fabrication of hybrid solar cell using doped zinc blend based semiconductor quantum dots (QDs) prepared by a simple wet chemical precipitation method. Formation of quantum dot has been ascertained by X-ray Diffraction (XRD), UV-visible Spectroscopy and Impedance Spectroscopy measurements. XRD studies established the zinc-blende phase in quantum dot regime. UV-visible studies reveal decrement in optical bandgap of the QDs with co-doping of Cd ion in ZnS lattice. Mott-Schottky analysis revealed n-type conductivity with increasein band bending from binary to ternary configuration respectively. Bulk heterojunction hybrid solar cells fabricated in 1cm X 1cm size in conjunction with p type Polypyrroleunder AM 1.5 illumination resulted in highest conversion efficiency of 1.6 %.

Synthesis of a conjugated pyrrolopyridazinedione\u2013benzodithiophene (PPD\u2013BDT) copolymer and its application in organic and hybrid solar cells

Herein, we describe the synthesis and characterization of a conjugated donor–acceptor copolymer consisting of a pyrrolopyridazinedione (PPD) acceptor unit, and a benzodithiophene (BDT) donor unit. The polymerization was done via a Stille cross-coupling polycondensation. The resulting PPD–BDT copolymer revealed an optical bandgap of 1.8 eV and good processability from chlorobenzene solutions. In an organic solar cell in combination with PC70BM, the polymer led to a power conversion efficiency of 4.5%. Moreover, the performance of the copolymer was evaluated in polymer/nanocrystal hybrid solar cells using non-toxic CuInS2 nanocrystals as inorganic phase, which were prepared from precursors directly in the polymer matrix without using additional capping ligands. The PPD–BDT/CuInS2 hybrid solar cells showed comparably high photovoltages and a power conversion efficiency of 2.2%.Graphical abstract

Structural, electronic and optical properties of CsPbX3 (X=Cl, Br, I) for energy storage and hybrid solar cell applications

Abstract Organic-Inorganic perovskites CsPbX3 (X = Cl, Br, I) are investigated for their potential ability and use as solar cells and energy storage materials, using density function theory, generalized gradient approximation and modified Becke-Johnson (TB-mBJ) exchange potential. Structural analysis shows that the lattice constant and unit cell volume varies when CsPbX3 (X = Cl, Br, I) change from cubic phase to tetragonal and orthorhombic structures. The electronic properties show that CsPbCl3, CsPbBr3 and CsPbI3 all are semiconductor in with bandgap between 0.79 eV and 2.54 eV. It is also observed that the bandgap changes when the structure changes. Optical properties show that these materials have a good absorption ability of photons due to their narrow bandgaps. The real e1(ω) and imaginary e2(ω) parts of their dielectric functions show that CsPbCl3, CsPbBr3 and CsPbI3 also possess a great ability of retaining the energy it absorbs. These properties make them very suitable for solar cells and energy storage applications. These materials also behave as superluminescent material at high photon energy.

Synthesis and characterization of nanostructures of ZnO and ZnO/Graphene composites for the application in hybrid solar cells

As an n-type inorganic semiconductor, ZnO has been widely used in hybrid solar cells (HSCs) due to its numerous characteristics such as low cost, easy synthesis, non-toxicity and good optoelectronic properties. In this work we have synthesized the ZnO nanostructures/nanoparticles via wet chemical route having Zinc Acetate Dihydrate (ZnADH) as precursor, Poly (Ethylene Glycol) block poly (Propylene Glycol) block poly (Ethylene Glycol) (PEG-PEG-PEG/P123) as template directing agent. Graphene oxide (GO) was prepared by the Modified Hummer's Method through the oxidation of graphite flakes and KMnO4 was used as an oxidizing agent. ZnO/Graphene nanocomposites were prepared via sonication process. Oxidation peaks of graphite showed by the UV–Vis spectroscopy were around 216 nm and all composite films were observed to be appeared in visible region. A considerable reduction in bandgap of ZnO from 3.1eV to 2.9eV was observed due to incorporation of graphene oxide which was confirmed with both UV–Vis bandgap analysis method and cyclic voltammetry (CV). Measureable progress in the performance of IV characteristics of hybrid solar cells was achieved using the ZnO/Graphene composite as electron collector in active layer along with P3HT:PCBM in an inverted hybrid photovoltaic device. Short circuit current was observed to be improved by approximately four times then its original value in these devices along with the increase in the concentration of GO whereas open circuit voltage showed a decreasing trend.

Efficient bulk heterojunction hybrid solar cells with graphene-silver nanoparticles composite synthesized by microwave-assisted reduction

Herein, we present a simple, eco-friendly one-step microwave-assisted reduction (MWAR) that can produce silver nanoparticles (Ag NPs) and reduced graphene oxide (rGO) in the form of Ag-rGO composites for application in heterojunction hybrid solar cells. The field-effect transistor fabricated with the MWAR Ag-rGO composite showed p-type behavior with a high mobility of 3.3×105cm2V−1s−1 and conductivity of 9×106S/m which is one-order of magnitude greater than pristine graphene (i.e., 1.59×105S/m). As-synthesized Ag-rGO composite was introduced into the active layer of bulk heterojunction solar cell based on P3HT:PCBM. Compared to the P3HT:PCBM only device (i.e., control device), the Ag-rGO implemented device showed a power conversion efficiency (PCE) of 4.23%, which is about 42% increase over the control device (i.e. PCE=2.98%). This dramatic increase in PCE was found to be mainly due to an increase in short-circuit current (Jsc) from 9.55 to 12.76mA/cm2 (about 33% increase), suggesting that the incorporation of p-type Ag-rGO into the active layer enhances the charge carrier generation and fast extraction of holes to the electrode. Furthermore, the Ag-rGO composite based solar cells without encapsulation showed remarkable air stability with retaining ~90% of its original PCE and ~93% of Jsc for 30 days under ambient environment, attributed to gas barrier feature of the randomly distributed graphene sheets.

Parameters study on the growth of GaAs nanowires on indium tin oxide by metal-organic chemical vapor deposition

After successful demonstration of GaAs nanowire (NW) epitaxial growth on indium tin oxide (ITO) by metal organic chemical vapor deposition, we systematically investigate the effect of growth parameters' effect on the GaAs NW, including temperature, precursor molar flow rates, growth time, and Au catalyst size. 40 nm induced GaAs NWs are observed with zinc-blende structure. Based on vapor-liquid-solid mechanism, a kinetic model is used to deepen our understanding of the incorporation of growth species and the role of various growth parameters in tuning the GaAs NW growth rate. Thermally activated behavior has been investigated by variation of growth temperature. Activation energies of 40 nm Au catalyst induced NWs are calculated at different trimethylgallium (TMGa) molar flow rates about 65 kJ/mol. The GaAs NWs growth rates increase with TMGa molar flow rates whereas the growth rates are almost independent of growth time. Due to Gibbs-Thomson effect, the GaAs NW growth rates increase with Au nanoparticle size at different temperatures. Critical radius is calculated as 2.14 nm at the growth condition of 430 °C and 1.36 μmol/s TMGa flow rate. It is also proved experimentally that Au nanoparticle below the critical radius such as 2 nm cannot initiate the growth of NWs on ITO. This theoretical and experimental growth parameters investigation enables great controllability over GaAs NWs grown on transparent conductive substrate where the methodology can be expanded to other III–V material NWs and is critical for potential hybrid solar cell application.

Atmospheric annealing effect on TiO2/Sb2S3/P3HT heterojunction hybrid solar cell performance

We investigate the low-cost, earth-abundant and air-stable inorganic absorber Sb2S3that can be processed in the air for organic–inorganic hybrid solar cell applications.

A Simple Approach Low-Temperature Solution Process for Preparation of Bismuth-Doped ZnO Nanorods and Its Application in Hybrid Solar Cells

A simple low-temperature solution processed bismuth-doped ZnO nanorods (NRs) and poly(3-hexylthiophene) (P3HT) were used as electron acceptor and donor, respectively, in a hybrid inorganic–organic photovoltaic system. Controlling Bi precursor concentration via solution processing (hydrothermal method) plays an important role in altering the morphology, structure, and intrinsic defects of ZnO NRs. Interstitial doping of Bi–Bi2O3 into ZnO (BiZO) NRs results in simultaneous improvement of the open circuit voltage and short circuit current density primarily due to prolonged charge carrier recombination lifetime, increased donor–acceptor interfacial areas with efficient exciton dissociation, and charge carrier mobility. As a result, the power conversion efficiency of the 2 wt % BiZO NRs-P3HT device was significantly enhanced by 55% compared with that of the pristine device. Overall, our study highlighted the immense potential of BiZO NRs as an excellent electron acceptor for fabrication of hybrid optoelectroni...