Sb2S3-based hybrid solar cells with electron transporting layer of TiO2 or ZnO nanoparticles in addition to poly(3-hexylthiophene)-2,5-diyl / (3, 4-ethylenedioxythiophene) : poly(styrene sulfonate), zinc phthalocyanine (ZnPc), or MoO3 for hole transporting layer were prepared and compared their photovoltaic properties with or without encapsulation by using glass and UV cut-off film. Among these hybrid solar cells, it was found that a combination of glass-ITO/TiO2/Sb2S3/ZnPC/Au encapsulated with glass and UV cut filter has the highest durability with keeping the relative power conversion efficiency of 90% through the stability test under 1 sun at 63 °C at a relative humidity of 50% for 1,500 h.

Organic-inorganic hybrid solar cells composed of glass/F-doped SnO2/TiO2/La-decorated or Zn-doped Sb2S3/ poly[(3hexylthiophene)-2,5-diyl]/poly [3-(3-carboxypropyl)thiophene-2,5diyl]/Au have been prepared and evaluated their photovoltaic performance. Using La-decorated Sb2S3 for hybrid solar cell resulted in 33% improvement of power conversion efficiency (PCE) as compared to that of the non-decorated Sb2S3 because of lowering the resistance at the interface, which was confirmed by the impedance analyses. It was found that the added La was phaseseparated and accumulated between the layers of TiO2 and Sb2S3. While doping of Zn into Sb2S3 resulted in the enlargement of the crystallite size of Sb2S3 from 14 nm to 25 nm. Utilization of Zndoped Sb2S3 for hybrid solar cell attained 57% enhancement of PCE. This result is ascribed to the effective lowering the bulkresistance.

Sb 2 S 3 -based hybrid solar cells were prepared in the combination with electron transporting layer of TiO 2 or ZnO nanoparticles in addition to poly(3-hexylthiophene)-2,5-diyl/(3, 4-ethylenedioxythiophene): poly(styrene sulfonate), zinc phthalocyanine (ZnPc), or MoO 3 for hole transporting layer. Photovoltaic performance and durability of the hybrid solar cells were compared each other with or without encapsulation by using glass and UV cutoff film. Among these hybrid solar cells, it was found that a combination of glass-ITO/TiO 2 /Sb 2 S 3 /ZnPC/Au encapsulated with glass and UV cut filter has the highest durability with keeping the relative power conversion efficiency of 90% through the stability test under 1 sun at 63 • C at a relative humidity of 50% for 1,500 h. 13 and so on and applied as the thin film for solar cell, which has been attained the power conversion efficiency (PCE) of 7.5%. 4 Although Sb 2 S 3 -based solar cell seems to be stable in air, 1,14 stability test under the accelerated conditions has not yet been reported. In addition, various materials such as TiO 2 , 1 ZnO, [15][16][17][18] or SnO 2 19 have been utilized as an electron transporting layer (ETL) and polythiophenes, 1-4 2,2',7,7'-tetrakis(N,Ndi-p-methoxyphenylamine)-9,9'-spirobifluorene, 20 ZnPc, CuSCN, 21MoO 3 , 22 or NiO 23 have been used as a hole transporting layer (HTL) of the Sb 2 S 3 based solar cells, however, optimization of the combinations of ETL and HTL in terms of the durability has also not yet been explored. In this context, we prepared Sb 2 S 3 -based solar cells with TiO 2 or ZnO nanoparticles for ETL in addition to poly(3-hexylthiophene)-2,5-diyl (P3HT)/ (3, 4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT: PSS), ZnPc, or MoO 3 for HTL and compared their photovoltaic properties with encapsulation by using glass and UV cutoff films under JIS C8938 conditions of 1 sun at 63• C at a relative humidity (RH) of 50%. ExperimentalPreparation of TiO 2 nanoparticle.-A 14.7 g of TiO 2 powder P-90 (Degussa, Evonic Japan Co., Ltd.) was dispersed in 62.3 g of 95% ethanol. After addition of 439 g of zirconia beads (φ 50 μm), the TiO 2 powder was ground with beads mill at 2000 rpm for 2 h. After the removal of the zirconia beads by filtration, ca. 60 g of TiO 2 slurry was obtained. Addition of adjusted amount of ethanol into the above TiO 2 sludge resulted in 6 wt% TiO 2 -dispersed solution.Preparation of ZnO nanoparticle.-ZnO nanoparticles were prepared according to the reported procedures 24 with slight modifications. Zinc acetate dihydrate (0.298 g) was dissolved in methanol (10 g) and stirred for 3 min with heating up to 65• C. 5 g of 3 wt% KOH in methanol was poured into the above solution and stirred for 2.5 h. After centrifugation at 20,000 rpm for 15 min and the removal of the supernatant, the crude precipitates were dispersed in 150 g of methanol through sonication. Thereafter, following another centrifugation at 20,000 rpm for 30 min and the removal of the supernatant, * Electrochemical Society Member.z E-mail:...

Organic-inorganic hybrid solar cells composed of glass/F-doped SnO2/TiO2/ SrTiO3/Sb2S3/ poly[(3-hexylthiophene)-2,5diyl]/poly [3-(3-carboxypropyl)thiophene-2,5-diyl]/Au have been prepared and evaluated their photovoltaic performance. Insertion of SrTiO3 layer between TiO2 and Sb2S3 interface resulted in the enhancement of the open circuit voltage (Voc) from 0.61 V to 0.70 V. The thickness, surface roughness, and sea-island structures of the Sb2S3 layer were optimized in terms of transmittance, reflectivity, short circuit current density (Jsc), fill factor (FF) and power conversion efficiency (PCE) by changing the the precursor concentration and rotation speed for spin-coating of the Sb2S3 layer. Through the above optimization, enhancements of Jsc from 8.6 mA cm -2 to 13.6 mA cm -2 and FF from 0.56 to 0.61 in addition to the improvement of PCE from 3.0% to 6.1% as compared with the device without the SrTiO3 layer were achieved.