No abstract

In this work, the SCAPS-1D program was utilized to perform simulations of ZnO/CuO/Cu 2 O thinfilm solar cells. Based on the cell structure and device fabrication process, solar cell structure parameters such as the thickness of the CuO layer, ZnO layer, donor density in the ZnO layer were evaluated in detail. The results indicated that an optimal structure of ZnO/CuO/Cu 2 O thin-film solar cell could be obtained when the thickness of the ZnO layer, CuO layer, and donor density in the ZnO layer is 100 nm, 500 nm, 1×10 17 cm −3 , respectively. The optimized solar cell structure of ZnO/CuO/Cu 2 O shows a potential efficiency of about 12% under the 1 sun air mass 1.5 G spectrum illumination. Besides that, the performance of the cell under individual solar concentrations and operating temperatures was also investigated.

Radial junction solar cells with vertically aligned wire arrays have been widely studied to improve the power conversion efficiency. In this work, we report the first Ge nanopillar solar cell. Nanopillar arrays are selectively patterned on p-type Ge (100) substrates using nanosphere lithography and deep reactive ion etching processes. Nanoscale radial and planar junctions are realized by an n-type Ge emitter layer which is epitaxially grown by MOCVD using isobutylgermane. In situ epitaxial surface passivation is employed using an InGaP layer to avoid high surface recombination rates and Fermi level pinning. High quality n-ohmic contact is realized by protecting the top contact area during the nanopillar patterning. The short circuit current density and the power conversion efficiency of the Ge nanopillar solar cell are demonstrated to be improved up to 18 and 30%, respectively, compared to those of the Ge solar cell with a planar surface.

The polymer gel solution consist of water soluble polymer preferably polyvinyl alcohol (PVA), plasticizing agent (glycerine) and chelating agents (citric acid) can decontaminate efficiency of 137 Cs and 84 Sr on the contaminated surfaces . Decontamination efficiency obtained from 95-99% on glass and stainless steel, ceramic and PVC plastic surfaces, which also depended on radioactivity and coating thickness. Optimization of film thickness is around 200 microns. Decontamination efficiency of Polymer gel were compared with DeconGel 1101 (product from USA) on surfaces. IR spectra studies indicated that Cs + and Sr 2+ ions interacted with PVA and citric acid in Polymer gel through C=O group. Mechanisms of this decontamination process have revealed.