Abstract

We present 10-nm thick metal alloys created by coevaporation of calcium and silver as transparent top electrode for inverted bulk heterojunction small-molecule organic solar cells (SMOSC). It is shown that such alloys exhibit sufficiently high conductivity to replace previously used thicker (>14 nm) pure Ag contacts. At the same time, Ca:Ag alloys have higher transmittance compared to pure Ag, which is desirable for semitransparent SMOSC where the light passes through the device and the metal contact. We find that a metal contact consisting of 1 nm Ag underlayer and 10 nm Ca:Ag of 1:1 mixing ratio (total Ag content by volume of 6 nm) on glass has an average transmittance in the visible range of 76% with a sheet resistance of 27.1 Ω/□, approaching the performance of ITO while being applied by a much gentler deposition method. Application of 10-nm thick alloys in semitransparent SMOSC lead to transmittance in the visible range Tvis of up to 49% and efficiency η of up to 2.3%, showing superior performance compared to devices with pure Ag top contacts.

Abstract

Metallic structures are an alternative in civil construction in terms of optimization of time and efficiency, about the construction process, besides being more versatile, durable, resistant and sustainable compared to other structures. Therefore, self-supporting metal towers have become indispensable in the expansion of large urban centers, due to the need for more slender, efficient and durable structures to the impacts caused by both man and the environment. However, its structures suffer daily from long sun exposure and contact with the atmosphere, which carries chemical elements that react with the material and cause pathologies such as thermal wear and chemical corrosion. Thus, the proposal of the work consists of analysing the behaviour and thermal performance of a metal tower with different metal alloys: ASTM A36, ASTM A570, and ASTM B338, thus determining density, capacity, and thermal conductivity. The model of the self-supporting tower used, is 36 meters high, opening the base of 15 meters, weighing throughout 209,730 kg and with a total of 1777 connecting elements distributed throughout the structure, shown in (Figure 1).