Kuanyu Yuan

SO ₂ , owing to its serious health and environmental risks, has driven the development of highly efficient materials for its capture and sequestration.

Perovskite solar cells (PSCs) with dopant-free hole transporting layers (HTLs) have attracted wide attention owing to their excellent photoelectric conversion efficiency and environmental stability. However, the hole transporting materials (HTMs) used to prepare dopant-free HTLs seriously hinder the commercial development of PSCs because of their high production cost and complicated preparation process. Herein, we chose thiophene as the central core to synthesize two low-cost HTMs, namely S1 and S2. Owing to the introduction of the ethylene bridge, the conjugated structure of S2 was expanded, and the steric hindrance of triphenylamine was reduced, which endowed S2 with a higher carrier mobility of 1.83 × 10⁻⁴ cm² V⁻¹ s⁻¹ than that of S1 with 6.3 × 10⁻⁵ cm² V⁻¹ s⁻¹. Furthermore, the S2-based PSCs provided an excellent power conversion efficiency of 20.13%, which was higher than those of PSCs based on S1 (18.01%). Besides, PSC devices with S1 and S2 as dopant-free HTL maintained more than 85% of their initial efficiency in air for 60 days. This work not only enriches the material system of dopant-free HTMs but also provides a simple and effective strategy for the preparation of low-cost and high-performance HTMs, paving the way for the commercialization of PSCs with dopant-free HTLs.

Benefiting from the expansion of the central structure, the carrier mobility of HTMs is elevated to 2.56 × 10 ⁻⁴ cm ² V ⁻¹ s ⁻¹ . Thus, the PCE of PSCs with dopant-free HTL is increased from 17.57% to 20.37%.

Covalent cross-linked porous organic polymers (POPs) have shown great potential in adsorption and separation fields owing to their high surface areas, easy functionalization, and porous design using synthetic strategies. Herein, we report the facile preparation of two triphenylamine-based nitrogen-rich porous organic polyaminals (TPOAs), denoted as TPOA-F and TPOA-OH, from triphenylamine-based triazine-hexamine and commercially available fluorine- and hydroxyl-monoaldehydes, respectively via a amine–aldehyde condensation reaction without any catalyst addition. These two resulting TPOAs possessed large specific surface areas (1179 and 565 m² g⁻¹) and hierarchical pore distribution (0.58 to 5.20 nm). Owing to this, TPOAs exhibited highly promising application potential for natural gas purification (mainly light hydrocarbons and CO₂ separation). Among them, TPOA-F shows the highest C₃H₈ uptake of 225 mg g⁻¹, C₂H₆ uptake of 122 mg g⁻¹, and CO₂ uptake of 155 mg g⁻¹ at 273 K/1 bar and C₃H₈ uptake of 187 mg g⁻¹, C₂H₆ uptake of 93 mg g⁻¹, and CO₂ uptake of 95 mg g⁻¹ at 298 K/1 bar. Then, the C₃H₈/CH₄, C₂H₆/CH₄, C₃H₈/C₂H₆, C₃H₈/CO₂, C₂H₆/CO₂, and CO₂/CH₄ gas mixture adsorption selectivities for TPOAs demonstrated the values of 68.7–78.8, 14.0–15.7, 4.9–5.0, 16.5–17.4, 3.4–3.5, and 4.2–4.5. Meanwhile, TPOAs also displayed considerable iodine capture performance up to 3.43 g g⁻¹. In addition, this has surpassed many reported porous polyaminal materials for their abundant porosity and nitrogen active sites, which offer host–guest interactions due to the high electron density. This study would provide valuable guidance for the development and application of efficient POP-based adsorption and separation materials.

High processing viscosity and poor solubility limit the application of heterocyclic polymers for fabricating organic wave‐transparent composites for aerospace applications. In this paper, a novel resin, poly(phthalazinone ether bisphenol fluorene) encapped with phthalonitrile (PPEBF‐Ph), was synthesized and used as the matrix. Biphenol‐based phthalonitrile monomer BP‐Ph was also synthesized and blended with PPEBF‐Ph to further lower the processing viscosity. Solubility tests showed that the resin was soluble in dimethylformamide, N,N‐dimethyl acetamide, N‐methylpyrrolidone, dimethyl sulfoxide, chloroform, and other solvents. Differential scanning calorimetry and rheological studies revealed that the mixed resins exhibited low processing viscosity and a wide processing window below the gel temperature. Thermogravimetric analysis indicated that the cured resins were stable below 510–530 °C under nitrogen atmosphere after 6 h of curing (decreased by 40–60% compared with previous reports on phthalonitrile resin). In air, the char yields of the resins reached 20–30% when heated at 800 °C. The composites were reinforced by a quartz fiber cloth and exhibited a dielectric constant of 2.94–3.27 in an electromagnetic field with frequency ranging from 8 to 18 GHz. Retention of the bending modulus exceeded 70% at 400 °C according to dynamic mechanical analysis, indicating excellent mechanical stability was obtained. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45976.