A systematic approach has been followed in the development of a high-efficiency hybrid photovoltaic device that has a combination of poly(3-hexylthiophene) (P3HT), [6,6]-phenyl C61-butyric acid methyl ester (PCBM), and silver nanowires (Ag NWs) in the active layer using the bulk heterojunction concept. The active layer is modified by utilizing a binary solvent system for blending. In addition, the solvent evaporation process after spin-coating is changed and an Ag NWs is incorporated to improve the performance of the hybrid photovoltaic device. Hybrid photovoltaic devices were fabricated by using a 1:0.7 weight ratio of P3HT to PCBM in a 1:1 weight ratio of o-dichlorobenzene and chloroform solvent mixture, in the presence and absence of 20 wt % of Ag NWs. We also compared the photovoltaic performance of Ag NWs embedded in P3HT:PCBM to that of silver nanoparticles (Ag NPs). Atomic force microscopy, scanning electron microscopy, transmittance electron microscopy, UV-visible absorption, incident photon-to-current conversion efficiency, and time-of-flight measurements are performed in order to characterize the hybrid photovoltaic devices. The optimal hybrid photovoltaic device composed of Ag NWs generated in this effort exhibits a power conversion efficiency of 3.91%, measured by using an AM 1.5G solar simulator at 100 mW/cm(2) light illumination intensity.

Small molecules based on N-atom-linked phenylcarbazole-fluorene as the main scaffold, end-capped with spirobifluorene derivatives, are developed as organic hole-transporting materials for highly efficient perovskite solar cells (PSCs) and bulk heterojunction (BHJ) inverted organic solar cells (IOSCs). The CzPAF-SBF-based devices show remarkable device performance with excellent long-term stability in PSCs and BHJ IOSCs with a maximum PCE of 17.21% and 7.93%, respectively.

LTG performed by experienced surgeons showed acceptable postoperative morbidity and mortality for patients with clinical stage I gastric cancer.

Recently, bipolar host materials are the most promising candidates for achieving high performance phosphorescent organic light-emitting diodes (PHOLEDs) in order to maximize recombination efficiency. However, the development of host material with high triplet energy (E T ) is still a great challenge to date to overcome the limitations associated with the present PHOLEDs. Herein, a highly efficient donor-π-acceptor (D-π-A) type bipolar host (4′-(9H-carbazol-9-yl)-2,2′-dimethyl-[1,1′-biphenyl]-4-yl)diphenylphosphine oxide (m-CBPPO) comprising of carbazole, 2,2′-dimethylbiphenyl and diphenylphosphoryl as D-π-A unit, respectively, is developed. Interestingly, a high E T of 3.02 eV is observed for m-CBPPO due to highly twisted conformation. Furthermore, the new host material is incorporated in PHOLEDs as emissive layer with a new carbene type Ir(cb) 3 material as a deep-blue emitter. The optimized devices show an excellent external quantum efficiency (EQE) of 24.8%with a notable Commission internationale de l'éclairage (x, y) ≤ 0.15, (0.136, 0.138) and high electroluminescence performance with extremely low efficiency roll-off. Overall, the above EQE is the highest reported for deep-blue PHOLEDs with very low efficiency roll-off and also indicate the importance of appropriate host for the development of high performance deep-blue PHOLEDs.

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The cost-effective hole transporting material ACR-TPA based on a 9,9-dimethyl-9,10-dihydroacridine core is synthesized and found to be a promising alternative to spiro-MeOTAD because of its comparable photovoltaic performance.

Three new highly efficient green-emitting heteroleptic phosphorescent iridium(III) complexes are designed and synthesized for the fabrication of solution-processable phosphorescent organic light-emitting diodes (PHOLEDs). Their photophysical, thermal, and electroluminescent (EL) properties are systematically investigated. The Ir(III) complexes comprise an amide-bridged trifluoromethyl (CF 3 )-substituted phenylpyridine unit as the main ligand and picolinic acid (pic) and tetraphenylimidodiphosphinate (tpip) as ancillary ligands. In addition, the 2-ethoxyethnol (EO 2 ) solubilizing group is attached to the 4-position of pic ancillary ligand via tandem reaction, which improved the absolute photoluminescence quantum yields (PLQYs) and EL performance. The high-performance solution-processable PHOLEDs based on the bis[5-methyl-8-trifluoromethyl-5H-benzo(c)(1,5)naphthyridin-6-one](4-(2-ethoxyethoxy picolinate) iridium(III) (Ir1) complex exhibit a maximum external quantum efficiency (EQE) of 24.22% and a maximum current efficiency (CE) of 92.44 cd A −1 , with the latter being among the best reported CEs achieved though solution processing. In contrast, PHOLEDs with the bis[5-hexyl-8-trifluoromethyl-5H-benzo(c)(1,5)naphthyridin-6-one] (tetraphenylimidodiphosphinato)iridium (Ir3) complex show extremely low efficiency roll-off, with an EQE max of 19.40% and an EQE of 19.29% at 10 000 cd m −2 .

The photoluminescence (PL) efficiency of emitters is a key parameter to accomplish high electroluminescent performance in phosphorescent organic light‐emitting diodes (PhOLEDs). With the aim of enhancing the PL efficiency, this study designs deep‐blue emitting heteroleptic Ir(III) complexes (tBuCN‐FIrpic, tBuCN‐FIrpic‐OXD, and tBuCN‐FIrpic‐mCP) for solution‐processed PhOLEDs by covalently attaching the light‐harvesting functional moieties (mCP‐Me or OXD‐Me) to the control Ir(III) complex, tBuCN‐FIrpic. These Ir(III) complexes show similar deep‐blue emission peaks around 453, 480 nm (298 K) and 447, 477 nm (77 K) in chloroform. tBuCN‐FIrpic‐mCP demonstrates higher light‐harvesting efficiency (142%) than tBuCN‐FIrpic‐OXD (112%), relative to that of tBuCN‐FIrpic (100%), due to an efficient intramolecular energy transfer from the mCP group to the Ir(III) complex. Accordingly, the monochromatic PhOLEDs of tBuCN‐FIrpic‐mCP show higher external quantum efficiency (EQE) of 18.2% with one of the best blue coordinates (0.14, 0.18) in solution‐processing technology. Additionally, the two‐component (deep‐blue:yellow‐orange), single emitting layer, white PhOLED of tBuCN‐FIrpic‐mCP shows a maximum EQE of 20.6% and superior color quality (color rendering index (CRI) = 78, Commission Internationale de L'Eclairage (CIE) coordinates of (0.353, 0.352)) compared with the control device containing sky‐blue:yellow‐orange emitters (CRI = 60, CIE coordinates of (0.293, 0.395)) due to the good spectral coverage by the deep‐blue emitter.