In order to obtain a simple and accurate calculation method of shielding effectiveness for woven fabric containing metal fiber yarns, a conductive grid structure model composed of two parallel metal yarn periodic arrays was established. The two periodic arrays were cross-arrangement. The calculation formula of shielding effectiveness for the fabric was deduced through the transfer matrix of the electromagnetic field. The theoretical value of shielding effectiveness of the fabric using the theoretical formula and the measured value tested by the shielding chamber method were compared. Both sets of data were analyzed respectively from the metallic yarn periodic spacing, diameter, electric conductivity, electromagnetic wave polarization direction, and the weaving angle. The result shows that a reasonable agreement between the theoretical value and the measured value has been achieved in a frequency range from 4 to 14 GHz. This shows that the theoretical calculation model is simple, highly precise, and is valuable for the design and development of fabric containing metal fiber yarns. It can be used for estimating the electromagnetic shielding effectiveness of the fabric.

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Compared with crystallized TiO 2 , amorphous Nb 2 O 5 has been applied in planar perovskite solar cell as electron transportation layer because of its excellent optical transmittance, low temperature preparation process, and similar Femi level with TiO 2 . However, the electron transfer rate is still limited by its low electron mobility and surface defect via room-temperature deposition process. Herein, a novel double buffer layer of [6,6]-phenyl-C61-butyric acid methyl ester(PCBM)/ionic liquid([EMIM]PF 6 ) has been inserted between perovskite and Nb 2 O 5 film. The PCBM could passive the surface of Nb 2 O 5 and improve electron extraction ability. The insert of [EMIM]PF 6 could improve the hydrophilic of PCBM and decrease the dissolution of PCBM in DMF during spin-coat perovskite precursor solution. A relatively high open voltage (over 1.09 V) and conversion efficiency of 18.8% have been achieved by using a double buffer layer which is the highest PCE of Nb 2 O 5 based perovskite solar cell to our best knowledge. The results indicate room temperature deposited Nb 2 O 5 can be a suitable candidate for replacing crystallized TiO 2 film and proposed modification strategy could facilitate the future development of interface modified layer for high efficient planar perovskite solar cell.

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