ACS Sustainable Chemistry & Engineering最新文献

Membrane-based postcombustion carbon capture is a promising method for reducing carbon dioxide (CO₂) emissions. Mobile carrier-facilitated transport membranes (FTMs) are receiving attention because they can simultaneously increase CO₂ permeability and CO₂/N₂ selectivity. However, FTMs still face the challenge of carrier loss. Stable immobilization of mobile carriers is essential for achieving and maintaining superior separation performance of FTMs. Herein, we report an ionic covalent organic framework (COF) membrane with confined mobile carriers for stable and efficient CO₂ separation. In this structure, a typical CO₂ mobile carrier, 2,5-diethylenetriamine (DETA), is stabilized in the negatively charged nanochannels of the COF membrane. Thanks to the intrinsic CO₂-facilitated transport of DETA, the COF membrane presents a CO₂ permeance of 2347 GPU and a CO₂/N₂ selectivity of 191 under simulated flue gas conditions. Because the CO₂ mobile carriers are firmly confined within the pores through electrostatic interactions, the membrane shows stable separation performance during the 310 h continuous test. The excellent performance and robust stability demonstrate the significant potential of this innovative membrane structure for practical use in the capture of CO₂ from flue gas.

Enhancing hole extraction and transfer of the hole transport layer (HTL) is urgently needed to achieve excellent performance perovskite solar cells. Herein, a novel phthalocyanine (TQ) has been introduced into Spiro-OMeTAD to finely optimize the hole transport properties of the HTL for achieving better performance. It is demonstrated that TQ incorporation can effectively enhance hole extraction/transfer and reduce charge recombination in the device. The TQ-treated device yields an improved power conversion efficiency of 24.29% from 21.91%. Remarkably, these unencapsulated devices demonstrate remarkable moisture, light, and thermal stabilities.

Producing high fructose syrup (HFS) is essential for both the platform chemicals and food industries. While enzyme-based methods are commonly used, their limited availability has led to growing interest in alkali metal catalysts. However, a complete understanding of these catalysts’ mechanism is still needed. Traditional alkaline earth metal oxides suffer stability issues due to metal leaching from solid surfaces. While Ba₃MgSi₂O₈ (BMS) is well-studied for its phosphor nature, its use as a Lewis base catalyst has not been explored. We present a novel method for the synthesis of BMS nanoparticles and demonstrate its application as a Lewis base for glucose to fructose (GLU-FRU) isomerization. In contrast to the conventional high-temperature solid-state grinding (1225 °C) of BaCO₃, MgO, and SiO₂, we synthesized crystalline single-phase BMS nanoparticles from BaCl₂ and hydrous magnesium silicates encapsulated in sporopollenin (BMS-ES2), utilizing a coprecipitation method at 400 °C. We attained a remarkable 62% glucose conversion rate, resulting in 56% fructose yield with 90.3% selectivity at 90 °C in 60 min at 25% glucose loading in H₂O, marking the highest reported values among catalysts containing alkaline earth metals in water. Further investigation using NMR and DFT revealed a proton exchange mechanism favoring Ba(OH)₂ due to water dissociation at Ba sites over Mg sites. The catalyst displayed excellent reusability, with a minimal 2–4% yield decrease per cycle over five cycles. These results not only provide insights into sustainable synthesis methods for Ba₃MgSi₂O₈ but also illuminate its catalytic properties for base-catalyzed reactions and the proton exchange mechanism involved in GLU-FRU isomerization. Ba₃MgSi₂O₈ nanoparticles are sustainably synthesized from biomass waste and catalyze gram scale GLU-FRU conversion in water with excellent selectivity and reusability.