@article{SisLab3019,
          volume = {6},
          number = {30759},
           month = {July},
          author = {Uisik Kwon and Bong-Gi Kim and Duc Cuong Nguyen and Jong-Hyeon Park and Na Young Ha and Seung-Joo Kim and Seung Hwan Ko and Soonil Lee and Daeho Lee and Hui Joon Park},
           title = {Solution-Processible Crystalline NiO Nanoparticles for High-Performance Planar Perovskite Photovoltaic Cells},
       publisher = {Nature Publishing Group},
            year = {2016},
         journal = {Scientific Reports},
             doi = {10.1038/srep30759},
           pages = {1--5},
             url = {https://eprints.uet.vnu.edu.vn/eprints/id/eprint/3019/},
        abstract = {In this work, we report on solution-based p-i-n-type planar-structured CH3NH3PbI3 perovskite 
photovoltaic (PV) cells, in which pre-crystallized NiO nanoparticles (NPs) without post-treatment are 
used to form a hole transport layer (HTL). X-ray diffraction and high-resolution transmission electron 
microscopy showed the crystallinity of the NPs, and atomic force microscopy and scanning electron 
microscopy confirmed the uniform surfaces of the resultant NiO thin film and the subsequent perovskite 
photoactive layer. Compared to the conventional poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) HTL, the NiO HTL had excellent energy-level alignment with that of CH3NH3PbI3 
and improved electron-blocking capability, as analyzed by photoelectron spectroscopy and diode 
modeling, resulting in Voc {\texttt{\char126}}0.13 V higher than conventional PEDOT:PSS-based devices. Consequently, a 
power conversion efficiency (PCE) of 15.4\% with a high fill factor (FF, 0.74), short-circuit current density 
(Jsc, 20.2 mA?cm?2), and open circuit voltage (Voc, 1.04 V) having negligible hysteresis and superior air 
stability has been achieved.}
}