01830nas a2200241 4500008003900000022001300039245013000052210006900182260001100251300001400262490000800276520103900284653002701323653003701350653002201387653001801409100002201427700002001449700001701469700001401486700001901500856006901519 2013 d a0927024800aModeling of optical and energy performance of tungsten-oxide-based electrochromic windows including their intermediate states0 aModeling of optical and energy performance of tungstenoxidebased c1/2013 a129 - 1350 v1083 a

Tungsten-oxide-based electrochromic (EC) windows are currently the most robust and matured dynamic windows where the transmittance of visual light and near-infrared radiation can be controlled by a small applied voltage. In its standard application, the window is commonly either in its clear or colored state. In this contribution, we study the optical and energy performance of such window in the fully bleached and fully colored state as well as when it is kept in intermediate states. Different configurations in terms of placement of the EC layer stack and possible additional low-emissivity (low-E) coating within the insulated glass unit are considered. Using optical data and software tools we find that even a small coloration has a significant effect on the energy performance because the solar heat gain coefficient is readily reduced by the absorption of the EC layer stack. We compare the performance of the EC windows to commercially available solar-control (spectrally selective) low-E windows.

10aElectrochromic windows10aEnergy efficient window modeling10aEnergy simulation10aSmart windows1 aLim, Sunnie, H.N.1 aIsidorsson, Jan1 aSun, Lizhong1 aKwak, Leo1 aAnders, André uhttps://facades.lbl.gov/publications/modeling-optical-and-energy01800nas a2200169 4500008004100000050001500041245016500056210006900221300001400290490000700304520115200311100002001463700002501483700002301508700002301531856007601554 1998 eng d aLBNL-4182000aEllipsometry on Sputter Deposited Tin Oxide Films: Optical Constants Versus Stoichiometry Hydrogen Content, and Amount of Electrochemically Intercalated Lithium0 aEllipsometry on Sputter Deposited Tin Oxide Films Optical Consta a7734-77410 v373 a

Tin oxide thin films were deposited by reactive radio-frequency magnetron sputtering onto In2O3:Sn coated and bare glass substrates. Optical constants in the 300-2500 nm wavelength range were determined by a combination of variable-angle spectroscopic ellipsometry and spectrophotometric transmittance measurements. Surface roughness was modeled from optical measurements and compared with atomic-force microscopy. The two techniques gave consistent results. The fit between experimental optical data and model results could be significantly improved when it was assumed that the refractive index of the Sn oxide varied across the film thickness. Varying the oxygen partial pressure during deposition made it possible to obtain films whose complex refractive index changed at the transition from SnO to SnO2. An addition of hydrogen gas during sputtering led to lower optical constants in the full spectral range in connection with a blue shift of the band gap. Electrochemical intercalation of lithium ions into the Sn oxide films raised their refractive index and enhanced their refractive-index gradient.

1 aIsidorsson, Jan1 aGranqvist, Claes, G.1 avon Rottkay, Klaus1 aRubin, Michael, D. uhttps://facades.lbl.gov/publications/ellipsometry-sputter-deposited-tin