Sheet Resistance Of Transparent Electrode Research Articles

Circles of equal radii randomly placed on a plane: some rigorous results, asymptotic behavior, and application to transparent electrodes

We consider N circles of equal radii, r, having their centers randomly placed within a square domain of size with periodic boundary conditions (). When two or more circles intersect each other, each circle is divided by the intersection points into several arcs. We found the exact length distribution of the arcs. In the limiting case of dense systems and large size of the domain ( in such a way that the number of circle per unit area, n = N/L2, is constant), the arc distribution approaches the probability density function (PDF) , where is the central angle subtended by the arc. This PDF is then used to estimate the sheet resistance of transparent electrodes based on conductive rings randomly placed onto a transparent insulating film.

Fabrication of high aspect ratio nanogrid transparent electrodes via capillary assembly of Ag nanoparticles.

In this report, we describe the fabrication of periodic Ag nanogrid electrodes by capillary assembly of silver nanoparticles (AgNPs) along patterned nanogrid templates. By assembling the AgNPs into these high-aspect-ratio nanogrid patterns, we can obtain high-aspect-ratio nanogratings, which can overcome the inherent trade-off between the optical transmittance and the sheet resistance of transparent electrodes. The junction resistance between the AgNPs is effectively reduced by photochemical welding and post-annealing. The fabricated high-aspect-ratio nanogrid structure with a line width of 150 nm and a height of 450 nm has a sheet resistance of 15.2 Ω sq(-1) and an optical transmittance of 85.4%.

Variations of cell performance in ITO-free organic solar cells with increasing cell areas

This study examined the effects of a cell area on the cell performances in ITO-free organic solar cells (OSCs) based on poly(3-hexylthiophene) (P3HT) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM). Highly conductive poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films with two different sheet resistances (Rsh) were used as polymeric transparent anodes for cost-effective ITO-free OSCs. Changes in the power conversion efficiency (PCE), the fill factor (FF), the short-circuit current (Jsc), and the open-circuit voltage (Voc) that resulted from changing the cell area or sheet resistance of transparent electrodes were systematically investigated. With increasing cell area from 4.5 to 49.5 mm2, the device performance of ITO-free OSCs was continuously decreased mainly due to the decrease in the FF and the series resistance (Rs). In addition, the performance of OSCs was critically dependent on Rsh of the PEDOT:PSS electrode. Upon reducing Rsh of the polymer anode from ∼200 to ∼90 Ω/□, the FF and PCE showed better values at an identical large cell area and exhibited a relieved cell performance degradation with increasing cell area, suggesting that the sheet resistance of transparent electrodes is a dominant factor to limit cell efficiencies in practical large-area solar cells.

Effects of transparent electrode resistance on the performance characteristics of electrochemichromic cells

The performance characteristics of WO3 electrochemichromic cells have been studied in connection with the electrical resistance of transparent electrodes and a lumped resistor connected to the electrodes in series. The sheet resistance of transparent electrodes used and the resistance of lumped resistor used are in the range of 10–1250 Ω/⧠ and 10–2500 Ω, respectively. The thickness of the WO3 film is ∼2400 Å or ∼4300 Å, and the electrolyte is 1 N H2SO4 aqueous solution containing 10 vol % glycerol. The current pulse form and the change in optical transmittance of experimental cells under operation were observed, and the operating characteristics of electrochemichromic cells have been found to clearly depend on the sheet resistance of transparent electrodes and/or the resistance of a lumped resistor connected serially.