Tuning the porosity of zinc oxide electrodes: from dense to nanopillar films

Abstract

Thin films with tunable porosity are of high interest in applications such as gas sensing and antireflective coatings. We report a facile and scalable method to fabricate ZnO electrodes with tuneable porosity. By adjusting the substrate temperature and ratio of precursor gasses during lowpressure chemical vapor deposition we can accurately tune the porosity of ZnO films, from 0 up to 24%. The porosity change of the films from dense layer to separated nanopillars results in an effective refractive index reduction from 1.9 to 1.65 at 550 nm, as determined by optical and x-ray spectroscopy. The low-refractive-index ZnO films are incorporated into amorphous silicon solar cells demonstrating reflection losses reduction down to 4% in the visible wavelengths range.

Directly Assembled 3D Molybdenum Disulfide on Silicon Wafer for Efficient Photoelectrochemical Water Reduction

“…The θ‐ and λ‐dependent R of both the samples are smaller than that of the pristine TiO 2 /p‐type Si because of a gradient refractive index, 2.545/2.64/5.6 . The refractive index of the 3D MoS 2 structures covering 50% of the TiO 2 /p‐Si area was estimated to 2.545, considering the refractive index of the MoS 2 in parallel direction and areal density . More importantly, in the 3D MoS 2 /TiO 2 /p‐Si photocathode, the variation of R in both R versus θ and R versus λ is negligible, indicating that the 3D MoS 2 film has omnidirectional and broadband antireflective properties for p‐Si, presumably because of the size effect below the diffraction limit…”

“…The absorption spectra and optical reflectance data of different MoS 2 growth time were summarized in Figure S6 (Supporting Information). [35,36] More importantly, in the 3D MoS 2 /TiO 2 /p-Si photocathode, the variation of R in both R versus θ and R versus λ is negligible, indicating that the 3D MoS 2 film has omnidirectional and broadband antireflective properties for p-Si, presumably because of the size effect below the diffraction limit. Furthermore, the dramatic reduction of reflectance with the 15 min grown 3D MoS 2 /TiO 2 /p-Si substrate is observed.…”

Investigation of the impact of different ARC layers using PC1D simulation: application to crystalline silicon solar cells

“…From Ref. [25][26][27][28][29][30], experimentally obtained ARC values for different ARCs ranging from 250-1200 nm have been directly inputted in Eq. 4 and then in the simulation.…”

In Situ Surface Assembly Derived Ultralow Refractive Index MgF2–SiO2 Hybrid Film for Tri‐Layer Broadband Antireflective Coating

“…[1][2][3][4][5][6][7] Its realization usually needs FULL PAPER FULL PAPER FULL PAPER silica AR coating with refractive index ranging from 1.22 to 1.44 by mixing the base-catalyzed silica sol and acid-catalyzed silica sol in different proportions. [ 23 ] Jiang's group adopted this method to obtain a double-layer AR coating with high transmittance at 1064 and 532 nm simultaneously.…”