Ion-modulated radical doping of spiro-OMeTAD for more efficient and stable perovskite solar cells.

Record power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) have been obtained with the organic hole transporter 2,2',7,7'-tetrakis(,-di--methoxyphenyl-amine)9,9'-spirobifluorene (spiro-OMeTAD). Conventional doping of spiro-OMeTAD with hygroscopic lithium salts and volatile 4--butylpyridine is a time-consuming process and also leads to poor device stability. We developed a new doping strategy for spiro-OMeTAD that avoids post-oxidation by using stable organic radicals as the dopant and ionic salts as the doping modulator (referred to as ion-modulated radical doping).

Conformal quantum dot-SnO layers as electron transporters for efficient perovskite solar cells.

Improvements to perovskite solar cells (PSCs) have focused on increasing their power conversion efficiency (PCE) and operational stability and maintaining high performance upon scale-up to module sizes. We report that replacing the commonly used mesoporous-titanium dioxide electron transport layer (ETL) with a thin layer of polyacrylic acid-stabilized tin(IV) oxide quantum dots (paa-QD-SnO) on the compact-titanium dioxide enhanced light capture and largely suppressed nonradiative recombination at the ETL-perovskite interface. The use of paa-QD-SnO as electron-selective contact enabled PSCs (0.

Factors Associated with Complicated Grief in Students Who Survived the Sewol Ferry Disaster in South Korea.

Objective: The Sewol ferry disaster caused shock and grief in South Korea. The aim of this study was to identify the factors associated with symptoms of complicated grief (CG) among the surviving students 20 months after that disaster.

Methods: This study was conducted using a cross-sectional design and a sample of 57 students who survived the Sewol ferry disaster.

A Retrospective and Prospective Follow-up Study of Psychological Distress in the Danwon High School Survivors of the Sewol Ferry Disaster.

Objective: We monitored a group of students from Danwon High School who survived the Sewol ferry disaster for 27 months to examine the course of their psychological symptoms.

Methods: We performed a chart review at the Danwon High School Mental Health Center at the following time points (T): 9 months (T1), 12 months (T2), and 15 months (T3) after the disaster. Additionally, we performed a follow-up review at 27 months (T4).

Social Support as a Mediator of Posttraumatic Embitterment and Perceptions of Meaning in Life among Danwon Survivors of the Sewol Ferry Disaster.

Purpose: Our research was designed to test and explore the relationships among embitterment, social support, and perceptions of meaning in life in the Danwon High School survivors of the Sewol ferry disaster.

Materials And Methods: Seventy-five Sewol ferry disaster survivors were eligible for participation, and were invited to participate in the study 28 months after the disaster. Forty-eight (64%) survivors (24 males, 24 females) completed questionnaires; the Posttraumatic Embitterment Disorder (PTED) scale, the Functional Social Support Questionnaire (FSSQ), and the Meaning in Life Questionnaire (MLQ).

Conjugated polyelectrolyte hole transport layer for inverted-type perovskite solar cells.

Unlabelled: Organic-inorganic hybrid perovskite materials offer the potential for realization of low-cost and flexible next-generation solar cells fabricated by low-temperature solution processing. Although efficiencies of perovskite solar cells have dramatically improved up to 19% within the past 5 years, there is still considerable room for further improvement in device efficiency and stability through development of novel materials and device architectures. Here we demonstrate that inverted-type perovskite solar cells with pH-neutral and low-temperature solution-processable conjugated polyelectrolyte as the hole transport layer (instead of acidic

Pedot: PSS) exhibit a device efficiency of over 12% and improved device stability in air.

An organic surface modifier to produce a high work function transparent electrode for high performance polymer solar cells.

Modification of an ITO electrode with small-molecule organic surface modifier, 4-chloro-benzoic acid (CBA), via a simple spin-coating method produces a high-work-function electrode with high transparency and a hydrophobic surface. As an alternative to PEDOT:PSS, CBA modification achieves efficiency enhancement up to 8.5%, which is attributed to enhanced light absorption within the active layer and smooth hole transport from the active layer to the anode.

Boosting the power conversion efficiency of perovskite solar cells using self-organized polymeric hole extraction layers with high work function.

A self-organized hole extraction layer (SOHEL) with high work function (WF) is designed for energy level alignment with the ionization potential level of CH3 NH3 PbI3 . The SOHEL increases the built-in potential, photocurrent, and power conversion efficiency (PCE) of CH3 NH3 PbI3 perovskite solar cells. Thus, interface engineering of the positive electrode of solution-processed planar heterojunction solar cells using a high-WF SOHEL is a very effective way to achieve high device efficiency (PCE = 11.

Mixed solvents for the optimization of morphology in solution-processed, inverted-type perovskite/fullerene hybrid solar cells.

We investigate mixed solvents of N,N-dimethylformamide (DMF) and γ-butyrolactone (GBL) to produce the smooth surface of a perovskite film and uniform crystal domains. This ideal morphology from mixed solvents enhances the power conversion efficiency to over 6% by improving the exciton dissociation efficiency and reducing the recombination loss at both interfaces of PEDOT:PSS/perovskite and perovskite/PCBM.

Vapor coating method using small-molecule organic surface modifiers to replace N-type metal oxide layers in inverted polymer solar cells.

We investigate a simple fabrication method for vapor coating small-molecule organic interlayers as replacements for metal oxide films. The interfacial layers, which serve both as both surface modifiers to reduce the substrate work function and electron selective layers, maximize light absorption within the active layer while improving electron transport and compatibility between the active layer and cathode, leading to a ∼22% enhancement in power conversion efficiency and similar air stability compared to devices using a ZnO layer.

Inverted colloidal quantum dot solar cells.

An inverted architecture of quantum dot solar cells is demonstrated by introducing a novel ZnO method on top of the PbS CQD film. Improvements in device characteristics stem from constructive optical interference from the ZnO layer that enhances absorption in the PbS CQD layer. Outstanding diode characteristics arising from a superior PbS/ZnO junction provide a further electronic advantage.

Effects of ionic liquid molecules in hybrid PbS quantum dot-organic solar cells.

We investigated the effect of ionic liquid molecules (ILMs) in hybrid quantum dot-organic solar cells (HyQD-OSCs). The insertion of an ILM layer between PbS and phenyl-C61-butyric acid methyl ester (PCBM) can shift the band edge of PCBM closer to the vacuum level of PbS due to spontaneous dipole polarization. Because of this new architecture, improvements in device performance were achieved, including increases in open-circuit voltage (VOC, from 0.

Gold(I)-catalyzed intramolecular hydroamination of alkyne with trichloroacetimidates.

[reaction: see text] A study on the gold (I)-catalyzed intramolecular hydroamination of trichloroacetimidates derived from propargyl and homopropargyl alcohols is described. In the presence of 2-5 mol % of cationic Au(I) complex, a variety of trichloroacetimidates undergo efficient hydroamination under an exceptionally mild condition. An orthogonality of the current catalytic protocol with those using a stoichiometric electrophile as well as a preliminary synthetic application as a stable precursor of 2-acylamino-1,3-diene has been demonstrated.