L.R.A.K. Bandara

University of Peradeniya | UOP · Department of Physics

A PAN-based gel polymer electrolyte with possible iodide ion conductivity was prepared by incorporating a mixture of Pr4N+I−, iodine, EC and PC in PAN. Out of various compositions prepared and characterised, the sample with composition PAN (13%):EC (31%):PC (45%):Pr4N+I− (7%):I2 (4%) by weight ratio, exhibited the maximum room temperature (25°C) co...

Reduced graphene oxide (rGO)-coated flexible papers are effective in applications like bioelectrical electrodes, water purification, and sensors due to their interesting properties. rGO-coated paper is fabricated by vacuum filtration of graphene oxide (GO) and then reducing GO-coated paper using chemical or thermal reduction. Strong reducing agents...

Reduced graphene oxide (rGO) is a material with potentially interesting properties which leads to many applications. Paper-based rGO is effective in applications like bioelectrical electrodes, water purification and sensors. Fabrication of paper-based rGO begins with oxidizing graphite to graphene oxide (GO) and reducing paper-based GO using chemic...

This study investigated the use of graphene as a performance enhancer of the electrolyte for dye-sensitized solar cells (DSSC). The electrolyte is a major component that affects the performance of a DSSC, as it can govern both the efficiency and the stability of the solar cell. A gel polymer electrolyte, which shows higher long-term stability while...

The study is focused on exfoliating vein graphite into graphene using an unsophisticated and low-cost process through a non-oxidative production route. High-quality graphene production with low-cost methods that give high yields and suitable for large-scale production, using vein graphite is a challenge to address, though there are many methods for...

Electrospun poly (vinylidene fluoride) (PVdF) has been recognized as a potential candidate for making nano-generators in a broad range of applications. Through electrospinning, PVdF fiber films can be fabricated while enhancing the β-phase content within it. The electrospinning process was carried out with optimal parameters to obtain uniform and w...

Graphene is a monolayer of carbon atoms, bound in a hexagonal honeycomb lattice, and layers of graphene from graphite. It has attracted attention due to its wide range of possible applications and academic interests on its unique properties. However, graphene is not a rare substance, and there are over four million graphene layers in a 1 mm thick g...

Dye-sensitized solar cells (DSCs) have attracted a lot of attention due to their low cost, ease of fabrication and reasonable photon to current conversion efficiency compared to conventional silicon based solar cells. However, further improvements are needed to enhance the performance and also to reduce the cost of production in order to produce co...

A series of gel polymer electrolytes (GPEs) containing lithium bis(oxalato)borate (LiBOB), propylene carbonate (PC), and ethylene carbonate (EC) have been investigated. Poly(ethylene oxide) (PEO) was used as the polymer. First, a series of liquid electrolytes was prepared by varying the Li:O ratio and obtained the best composition giving the highes...

To supplement the ever increasing power demand in the present day world, supercapacitors have emerged as one of the suitable power storage devices. Redox capacitors have received a considerable attention due to factors such as high cycle ability, satisfactory specific capacitance and good stability. There are many reports on redox capacitors based...

Rechargeable lithium-ion batteries have emerged as an excellent candidate over nickel hydride and lead acid batteries due to their high gravimetric and volumetric energy. Recently, researchers paid their attention on developing gel polymer electrolytes (GPEs) to overcome problems occurred due to liquid electrolytes such as leakage and solvent evapo...

The enhancement in efficiency of N719 dye-sensitized solar cells (DSSCs) by a mixed cation iodide salt mixture is investigated. The gel electrolyte used in the glass/FTO/nano-porous TiO2/gel electrolyte, I2/Pt/FTO/glass solar cell structure, consists of tetrapropylammonium iodide (Pr4NI) and potassium iodide (KI) in a plasticized polyethyleneoxide...

a b s t r a c t This paper reports the effect of using a mixed iodide salt system with two dissimilar cat-ions to enhance the efficiency of dye-sensitized solar cells made with polyvinylidene-fluoride (PVdF) based gel electrolyte. Instead of a single iodide salt, a mixture of potassium iodide (KI) with a small K þ cation and tetrapropylammonium iod...

The Gel Polymer Electrolytes (GPEs) are promising materials for the ever-growing need for high energy density power sources such as lithium ion rechargeable batteries and dye sensitized solar cells. The use of GPE, which carrying both cohesive properties of solid and diffusive properties of liquid, overcomes many practical problems that solid and l...

Gel polymer electrolytes (GPEs) have been identified as a group of suitable alternative for liquid and solid electrolytes. They have shown excellent higher ionic conductivities than conventional polymer electrolytes. This paper reports about a gel polymer electrolyte based on the polymer, polymethylmethacrylate (PMMA) complexed with tetrapropylammo...

Gel Electrolytes (GEs) are a newest generation of electrolytes, which exhibit high ionic conductivities at room temperature (RT) compared to solid electrolytes and good mechanical properties and long term stability compared to liquid electrolytes. Present days GEs have been identified as more promising electrolyte materials for various practical ap...

Gel polymer electrolytes have been recognized as a suitable class of electrolytes in various electrochemical applications such as rechargeable cells, super capacitors and electrochromic devices. It is due to the fact that they show appreciable ionic conductivities while possessing good mechanical stabilities which are absent with many other electro...

Polymer electrolytes have been able to get the attraction of the researchers due to their interesting mechanical and physical properties and potential candidacy in various applications. But those systems have shown low ambient temperature conductivity. As a result of attempting to increase the conductivity, different categories of polymer electroly...

Portable electronic device industry is vastly developing over the last few years. As electrochemical batteries are suitable power sources for portable devices, demand for reliable and efficient batteries have also been increased. Since liquid electrolytes can cause several safety hazards due to leaking of the electrolyte, studies on gel polymer ele...

Gel polymer electrolytes are known to be very suitable for many electrochemical devices. They have been extensively studied for lithium based electrochemical cells. But, due to several drawbacks of lithium based cells such as safety issues, handling problems and toxicity, it is the time to develop non Li based cells. In this study, ionic conductivi...

Two gel or quasi-solid-state electrolyte complexes based on PAN (polyacrylonitrile) host polymer and salts Hex 4 NI (tetrahexylammonium iodide), MgI 2 , LiI were prepared by incorporating plasticizers EC (ethylene carbonate) and PC (propylene carbonate). These are: PAN/EC/PC/I 2 /Hex 4 NI:MgI 2 and PAN/EC/PC/I 2 /Hex 4 NI:LiI. A clear glass transit...

Gel Polymer Electrolytes (GPEs) are promising materials for the ever-growing need of high energy density power sources such as lithium ion batteries. The emphasis of this work is on a plasticized polyacrylonitrile (PAN) and lithium tetrafluoroborate (LiBF4) based GPE system with and without ceramic filler titania (TiO2). As the plasticizer, a mixtu...

Polymer Electrolytes (PEs) have been studied to use in many devices such as lithium rechargeable batteries, fuel cells, electrochromic devices, etc. Most of the previous research work has been carried out to study the cation conductivity of PEs and their conductivity enhancement with the addition of various fillers. There are not many reports on st...

Solid polymer electrolyte PEO9 Mg(ClO4)2 incorporating 10 wt.% nano-porous Al2O3 filler grains has been prepared by the solvent casting technique using acetonitrile as the common solvent. Al2O3 powder (activated acidic, Aldrich) with grain size 104 μm and pore size 5.8 nm were incorporated as an inert filler. Electrolyte films have been characteriz...

Two types of photolectrochemical (PEC) solar cells, FTO/TiO2/dye/PAN, EC, PC, Pr4N+I−, I2/Pt/FTO, and FTO/TiO2/dye/PEO, EC, PC, KI/I2/Pt/FTO have been fabricated using a PAN-based gel polymer electrolyte and a PEO-based plasticised polymer electrolyte. The PAN-based gel electrolyte, made of polyacrylonitrile (PAN), ethylene carbonate (EC), propylen...

A number of Cu++ ion conducting, poly(ethylene oxide) (PEO) based solid polymer electrolytes exhibit interesting electrochemical properties. In particular, the polymer electrolyte PEO9:Cu(CF5SO3)2 made by complexing copper triflate (CuTf2) with PEO appears to show scientifically intriguing transport properties. Although copper ion transport in thes...

In this work, the effect of addition of the inert filler α-Al2O3 on the conductivity enhancement of the plasticized, PEO based solid polymer electrolytes has been studied. By this method, conductivities of the order of 10⁻⁵ S cm⁻¹ at room temperature has been obtained by the addition of inert ceramic powder, α-(Al2O3) of grain size 0.3 μm, to a pla...

The conductivity and dielectric response of poly(ethylene oxide) (PEO) based plasticized polymer electrolyte systems were studied in the broad frequency range from 5 Hz to 1.8 GHz and in the temperature range from 248 K to 353 K. Propylene carbonate (PC) and ethylene carbonate (EC) were used as conventional plasticizers while poly(perfluorinated e...

The ionic conductivity of the system P(EO)9/LiCF3SO3 may be increased by two orders of magnitude at room temperature by adding poly(perfluorinated ethylenmethylenoxide) (PPFEMO). The highest conductivity at 20°C, 4.0×10−5 Ω−1cm−1, was obtained for a ratio PPFEMO/PEO=1.00. The conductivity is enhanced when the amount of plasticizer is increased, how...

Many polymer electrolytes used in practical applications contain a low molecular weight plasticizer. Plasticizers can be used to change the mechanical and electrical properties of polymer electrolytes by reducing the degree of crystallinity and lowering the glass transition temperatureTg. In this study the ionic conductivity has been determined for...