ABSTRACT
For several years now, organic-inorganic hybrid perovskite materials have shown remarkable progress in the field of opto-electronic devices. Herein, we introduce a cathode-side passivation layer of poly(methyl methacrylate) (PMMA) for a highly efficient and stable self-powered CH3NH3PbI3 perovskite-based photodiode. For effective noise-current suppression, the PMMA passivation layer was employed between a light-absorbing layer of CH3NH3PbI3 (MAPbI3) perovskite and an electron transport layer of [6,6]-phenyl-C61-butyric acid methyl ester. Due to its passivation effect on defects in perovskite film, the PMMA passivation layer can effectively suppress interface recombination and reduce the leakage/noise current. Without external bias, the MAPbI3 photodiode with the PMMA layer demonstrated a significantly high specific detectivity value (~1.07 × 1012 Jones) compared to that of a conventional MAPbI3 photodiode without a PMMA layer. Along with the enhanced specific detectivity, a wide linear dynamic response (~127 dB) with rapid rise (~50 µs) and decay (~17 µs) response times was obtained. Furthermore, highly durable dynamic responses of the PMMA-passivated MAPbI3 photodiode were observed even after a long storage time of 500 h. The results achieved with the cathode-side PMMA-passivated perovskite photodiodes represent a new means by which to realize highly sensitive and stable self-powered photodiodes for use in developing novel opto-electronic devices.
ABSTRACT
Organohalide perovskite materials and related optoelectronic applications have drawn significant attention due to their promising high-performance photon-to-electricity conversion efficiencies. Herein, we demonstrate a highly sensitive self-powered perovskite-based photodetector created with a noise-current-suppressible passivation layer of poly(methyl methacrylate) (PMMA) at the interface between a CH3NH3PbI3 light-absorbing layer and a NiOx hole-transporting layer. Along with the defect passivation effect, the PMMA layer effectively diminishes unwanted carrier recombination losses at the interface, resulting in a significant reduction of the leakage/noise current. Consequently, without external bias, a remarkably high level of specific detectivity (â¼4.5 × 1013 Jones from the dark current and â¼0.81 × 1012 Jones from the noise current) can be achieved due to the use of the PMMA passivation layer, greatly exceeding those of conventional unpassivated perovskite devices. Moreover, we observed a very wide linear dynamic response range of â¼129â dB together with rapid rise and decay response times of â¼52 and â¼18 µs, respectively. Overall, these results provide a solid foundation for advanced interface-engineering to realize high-performance self-powered perovskite photodetectors for various optoelectronic applications.
ABSTRACT
Primary lymphoma of bone (PLB) is an uncommon entity and is extremely rare in the foot and ankle. In this case, PLB was identified from the bone specimen after a bunionectomy of the first and fifth metatarsals. The diagnosis was confirmed with pathologic analysis, genetic karyotyping, positron emission and computed tomography scans, and fluorescence in situ hybridization (FISH). We felt that reporting this case was essential due to the rarity of its pedal occurrence and the lack of preoperative signs or symptoms.
