Interfacial Layer Materials with a Truxene Core for Dopant-Free NiO-Based Inverted Perovskite Solar Cells.

Nickel oxide (NiO) is commonly used as a holetransporting material (HTM) in p-i-n perovskite solar cells. However, the weak chemical interaction between the NiO and CHNHPbI (MAPbI) interface results in poor crystallinity, ineffective hole extraction, and enhanced carrier recombination, which are the leading causes for the limited stability and power conversion efficiency (PCE). Herein, two HTMs, TRUX-D1 (N,N,N-tris(9,9-dimethyl-9H-fluoren-2-yl)-5,5,10,10,15,15-hexaheptyl-N,N,N-tris(4-methoxyphenyl)-10,15-dihydro-5H-diindeno[1,2-a:1',2'-c]fluorene-2,7,12-triamine) and TRUX-D2 (5,5,10,10,15,15-hexaheptyl-N,N,N-tris(4-methoxyphenyl)-N,N,N-tris(10-methyl-10H-phenothiazin-3-yl)-10,15-dihydro-5H-diindeno[1,2-a:1',2'-c]fluorene-2,7,12-triamine), are designed with a rigid planar C symmetry truxene core integrated with electron-donating amino groups at peripheral positions.

3D-Printed Collagen-Based Waveform Microfibrous Scaffold for Periodontal Ligament Reconstruction.

Reconstruction of the periodontal ligament (PDL) to fulfill functional requirement remains a challenge. This study sought to develop a biomimetic microfibrous system capable of withstanding the functional load to assist PDL regeneration. Collagen-based straight and waveform microfibers to guide PDL cell growth were prepared using an extrusion-based bioprinter, and a laminar flow-based bioreactor was used to generate fluidic shear stress.

Core-Shell poly-(D,l-Lactide-co-Glycolide)-chitosan Nanospheres with simvastatin-doxycycline for periodontal and osseous repair.

This study aimed to evaluated the potential of core-shell poly(D,l-lactide-co-glycolide)-chitosan (PLGA-chitosan) nanospheres encapsulating simvastatin (SIM) and doxycycline (DOX) for promoting periodontal and large-sized osseous defects. SIM, and/or DOX were encapsulated in PLGA-chitosan nanospheres using double emulsion technique and were delivered to sites of experimental periodontitis and large-sized mandibular osseous defects of rats for 1-4 weeks. The resultant nanospheres were ~ 200 nm diameter with distinct core-shell structure and released SIM and DOX sustainably for 28 days.

Commercially available jeffamine additives for p-i-n perovskite solar cells.

Commercially available Jeffamines (polyetheramine) with average molecular weights of 2000 and 3000 g mol; one (M2005), two (D2000), and three (T3000) primary amino groups end-capping on the polyether backbone; and propylene oxide (PO) and ethylene oxide (EO) functionality were explored as additives for application in MAPbI perovskite solar cells (PSCs). The results indicated that the embedding of Jeffamine additives effectively passivates the defects in the grain boundaries of perovskite through the coordination bonding between the nitrogen atom and the uncoordinated lead ion of perovskite. We fabricated p-i-n PSC devices with the structure of glass/indium tin oxide (ITO)/NiO/CHNHPbI (with and without Jeffamine)/PCBM/BCP/Ag.

Defect Passivation by Amide-Based Hole-Transporting Interfacial Layer Enhanced Perovskite Grain Growth for Efficient p-i-n Perovskite Solar Cells.

In this study, we synthesized four acceptor-donor-acceptor type hole-transporting materials (HTMs) of for an HTMs/interfacial layer with carbazole as the core moiety and ester/amide as the acceptor unit. These HTMs contain 4-hexyloxyphenyl substituents on the carbazole N atom, with extended π-conjugation achieved through phenylene and thiophene units at the 3,6-positions of the carbazole. When using amide-based HTMs as a dopant-free HTM in a p-i-n perovskite solar cell (PSC), we achieved a power conversion efficiency (PCE) of 13.

Embedding a Diketopyrrolopyrrole-Based Cross-linking Interfacial Layer Enhances the Performance of Organic Photovoltaics.

In this study, we prepared DPPBTDA, a diketopyrrolopyrrole-based small molecule presenting a terminal cross-linkable azido group, as a cathode modifying layer for organic photovoltaics (OPVs) having the inverted device structure glass/indium tin oxide/zinc oxide (ZnO) with or without the interfacial layer (IFL)/active layer/MoO/Ag. The active layer comprising a blend of poly[4,8-bis(5-(2-ethylhexyl)thien-2-yl)benzo[1,2- b;4,5- b']dithiophene-2,6-diyl- alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4- b]thiophene)-2-carboxylate-2,6-diyl] (PTB7-Th) as the electron donor and [6,6]-phenyl-C-butyric acid methyl ester (PCBM) as the electron acceptor. Atomic force microscopy, space-charge-limited current mobility, surface energy, electron spectroscopy for chemical analysis depth profile, ultraviolet photoelectron spectroscopy analysis, and OPV performance data revealed that the surface status of ZnO changed after inserting the DPPBTDA/PCBM hybrid IFL and induced an optimized blend morphology, having a preferred gradient distribution of the conjugated polymer and PCBM, for efficient carrier transport.

Perovskite photovoltaics featuring solution-processable TiO2 as an interfacial electron-transporting layer display to improve performance and stability.

In this study we used solution-processable crystalline TiO2 nanoparticles as an interfacial modified layer between the active layer and aluminum cathode to fabricate CH3NH3PbI3/PCBM-based planar heterojunction perovskite photovoltaic (PPV) devices. We optimized the performance of the PPV device prepared without TiO2 by varying the preheating temperature of the indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene) (PEDOT) substrate, obtaining a power conversion efficiency (PCE) of 6.3% under simulated AM 1.

Two-step thermal annealing improves the morphology of spin-coated films for highly efficient perovskite hybrid photovoltaics.

In this paper, we describe relationships between the morphologies and the power conversion efficiencies (PCE) of perovskite photovoltaics having a conventional p-i-n heterojunction structure, indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS)/CH(3)NH(3)PbI(3-x)Cl(x)/PC(61)BM/Al. The PCE of such a device is highly dependent on the morphology of the perovskite film, which is governed by the concentrations of its precursors and the annealing conditions. A two-step annealing process allowed sufficient crystallization of the perovskite material, with a high coverage at a high precursor concentration.

Increasing the open-circuit voltage in high-performance organic photovoltaic devices through conformational twisting of an indacenodithiophene-based conjugated polymer.

A fused ladder indacenodithiophene (IDT)-based donor-acceptor (D-A)-type alternating conjugated polymer, PIDTHT-BT, presenting n-hexylthiophene conjugated side chains is prepared. By extending the degree of intramolecular repulsion through the conjugated side chain moieties, an energy level for the highest occupied molecular orbital (HOMO) of -5.46 eV--a value approximately 0.