High-Performance Green and Blue Light-Emitting Diodes Enabled by CdZnSe/ZnS Core/Shell Colloidal Quantum Wells.

The unique anisotropic properties of colloidal quantum wells (CQWs) make them highly promising as components in nanocrystal-based devices. However, the limited performance of green and blue light-emitting diodes (LEDs) based on CQWs has impeded their practical applications. In this study, alloy CdZnSe core CQWs with precise compositions are tailored via direct cation exchange (CE) from CdSe CQWs with specific size, shape, and crystal structure and utilized hot-injection shell (HIS) growth to synthesize CdZnSe/ZnS core/shell CQWs exhibiting exceptional optoelectronic characteristics.

Benefits of the Hydrophobic Surface for CHNHPbI Crystalline Growth Towards Highly Efficient Inverted Perovskite Solar Cells.

In inverted perovskite solar cells (PSCs), high-quality perovskite film grown on hole-transporting material (HTM) with pinhole-free coverage and a large grain size is crucial for high efficiency. Here, we report on the growth of pinhole-free and large grain CHNHPbI crystals favored by a hydrophobic small molecular HTM, namely, 4,4'-Bis(4-(di-p-toyl)aminostyryl)biphenyl (TPASBP). The hydrophobic surface induced by TPASBP suppressed the density of the perovskite nuclei and heterogeneous nucleation, thus promoting the perovskite to grow into a dense and homogeneous film with a large grain size.

Highly Efficient and Operational Stability Polymer Solar Cells Employing Nonhalogenated Solvents and Additives.

The power conversion efficiencies (PCEs) of potential polymer solar cells have been shown to rapidly exceed 15%. However, these high-performance devices are based on halogenated solvents that pose a significant hazard to the atmospheric environment and human beings. The use of nonhalogenated solvents makes the device less efficient because of its solubility issues.

Improving the Charge Carrier Transport and Suppressing Recombination of Soluble Squaraine-Based Solar Cells via Parallel-Like Structure.

Small molecule organic solar cells (SMOSCs) have attracted extensive attention in recent years. Squaraine (SQ) is a kind of small molecule material for potential use in high-efficiency devices, because of its high extinction coefficient and low-cost synthesis. However, the charge carrier mobility of SQ-based film is much lower than other effective materials, which leads to the pretty low fill factor (FF).

An Azulene-Containing Low Bandgap Small Molecule for Organic Photovoltaics with High Open-Circuit Voltage.

A simple azulene-containing squaraine dye (AzUSQ) showing bandgap of 1.38 eV and hole mobility up to 1.25×10(-4)  cm(2)  V(-1)  s(-1) was synthesized.

Highly Efficient p-i-n Perovskite Solar Cells Utilizing Novel Low-Temperature Solution-Processed Hole Transport Materials with Linear π-Conjugated Structure.

Alternative low-temperature solution-processed hole-transporting materials (HTMs) without dopant are critical for highly efficient perovskite solar cells (PSCs). Here, two novel small molecule HTMs with linear π-conjugated structure, 4,4'-bis(4-(di-p-toyl)aminostyryl)biphenyl (TPASBP) and 1,4'-bis(4-(di-p-toyl)aminostyryl)benzene (TPASB), are applied as hole-transporting layer (HTL) by low-temperature (sub-100 °C) solution-processed method in p-i-n PSCs. Compared with standard poly(3,4-ethylenedioxythiophene): poly(styrenesulfonic acid) (PEDOT:PSS) HTL, both TPASBP and TPASB HTLs can promote the growth of perovskite (CH NH PbI ) film consisting of large grains and less grain boundaries.

Revealing the Effect of Additives with Different Solubility on the Morphology and the Donor Crystalline Structures of Organic Solar Cells.

The impact of two kinds of additives, such as 1,8-octanedithiol (ODT), 1,8-diiodooctane (DIO), diphenylether (DPE), and 1-chloronaphthalene (CN), on the performance of poly[(5,6-difluoro-2,1,3-benzothiadiazol-4,7-diyl)-alt-(3,3‴-di(2-octyldodecyl)2,2';5',2″;5″,2‴-quaterthiophen-5,5‴-diyl)] (PffBT4T-2OD):[6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) based polymer solar cell are investigated. The polymer solar cells (PSCs) of PffBT4T-2OD:PC71BM by using CN show a more improved PCE of 10.23%.

Improved performances of PCDTBT:PC71BM BHJ solar cells through incorporating small molecule donor.

We demonstrate bulk heterojunction (BHJ) organic photovoltaics (OPVs) with a power conversion efficiency (PCE) of 6.39% by incorporating a small molecular compound 2-[4-(N-butyl-N-phenylamino)-2,6-dihydroxyphenyl]-4-[(4-(N-butyl-N-phenylamino)-2,6-dihydroxyphenyl)-2,5-dien-1-ylidene]-3-oxocyclobut-1-en-1-olate (SQ-BP) as the additional donor material into a poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl] (PCDTBT):[6,6]-phenyl C71 butyric acid methyl ester (PC71BM) host binary blend. Incorporating SQ-BP into the PCDTBT:PC71BM host blend film increases the photon harvesting of a ternary photovoltaic device with a broad absorption spectrum from 300 nm to 750 nm, which results in an increased short-circuit current density (Jsc).

Asymmetrical squaraines for high-performance small-molecule organic solar cells with a short circuit current of over 12 mA cm(-2).

An asymmetrical squaraine dye (Py-3) with its two electron-donating aryl groups directly linked to the electron-withdrawing squaric acid core possesses an ideal bandgap of 1.33 eV, together with an intense and broad absorption band in the range 550-950 nm. Hence, the resulting solution-processed solar cells display an impressive Jsc of 12.

A low bandgap asymmetrical squaraine for high-performance solution-processed small molecule organic solar cells.

A novel asymmetrical squaraine ASQ-5 bearing indoline as an end capper exhibits a low bandgap of 1.43 eV and a broad absorption band in the Vis-NIR region of 550-850 nm in thin films, hence renders solution-processed organic solar cells with an impressive Jsc of up to 11.03 mA cm(-2) and an excellent PCE of 4.