Latest ArticlesOptimal bulk-heterojunction (BHJ) morphology is crucial for efficient charge transport and good photovoltaic performance in organic solar cells (OSCs). Yet, the correlation between chemical structures of nonfullerene acceptors (NFAs) and molecular interaction in the BHJ blends remains opaque. Herein, we study three isomeric NFAs referred to as MQ1-x (x = β, γ, or δ) that shared an asymmetric selenophene-fused heteroheptacene backbone end-capped by two monochlorinated end groups. Remarkably, miscibility between the polymer donor of PM6 and MQ1-x successively elevates as the chlorine atoms move from β-, to γ-, to δ-position of terminals. Combined with the varied molecular crystallinity of these NFAs, diverse BHJ morphologies are observed in their blend films. As a result, the MQ1-δ-based devices present the highest PCE of 12.08% owing to the efficient charge dissociation and transport induced by the compact molecular packing and optimal BHJ morphology. Our investigation provides a new insight in the material design that has a good balance in molecular packing and film morphology for high-performance OSCs.
The CO2 photoconversion is sensitive to the local reaction environment, of which activity and selectivity can be regulated by the change of reaction systems. This paper focuses on investigating the photocatalytic CO2 reduction behaviors of MOFs with the involvement of water under different reaction modes, including gas-solid and liquid-solid systems. The CO2 photoreduction in a liquid-solid system shows high performance in generating HCOOH with the selectivity of 100%. In contrast, the gas-solid system referring to the synergistic interaction of MOFs and H2O vapor benefits to the formation of gas-phase products, such as CO and CH4. The possible mechanisms of photocatalytic CO2 reaction in two modes were investigated by in-situ Fourier-transform infrared spectroscopy, which indicates that the distinction in reaction consequence may result from the difference in CO2 chemisorbed modes and the proton provision. The choice of reaction system plays an important role in the achievement of high efficiency and selectivity for photocatalytic CO2 reduction, which is of great practical value in real-world applications.
Ring-opening copolymerization of CO2 and epoxides is a promising way to manufacture high value-added materials. Despite a variety of catalyst systems have been reported, the reaction is still limited by low activity and polymer selectivity. Herein, a strategy of polymerization-enhanced Lewis acidity is reported to construct a series of highly efficient polymeric aluminum porphyrin catalysts (PAPCs). The characterization of the coordination equilibrium constant (Keq) showed significantly enhanced Lewis acidity of PAPC (Keq = 18.2 L/mol) compared to the monomeric counterpart (Keq = 6.4 L/mol), accompanied with increased turnover frequency (TOF) from 136 h−1 to 5500 h−1. Through detailed regulation of Lewis acidity, the highly Lewis acidic PAPC-OTs displayed a record high TOF of 30,200 h−1 with polymer selectivity of up to 99%.
Wettability transition is a significant responsive mechanism which is widely applied to construct smart materials and systems. The broad-spectrum responsiveness of the wettability transition makes it a promising way to expand innovative applications. Here, we develop a track-guided self-transportation system mediated by sequential wettability transition accompanied with capillary transportation. Alkaline fuel is loaded into polydimethylsiloxane (PDMS) cuboid to trigger the wettability transition of distributed superhydrophobic tracks laid in shallow water. After the wettability transition, the induced capillary force can propel the repetitive track-to-track transportation of PDMS. Importantly, the spacing between adjacent tracks is rationally designed based on multiple factors including threshold of wettability transition, diffusion kinetics and capillary interaction. Furthermore, the track-guided transportation system is applied to realize directed self-assembly of multiple PDMS building blocks for designated configuration, which increases the complexity and intelligence of self-assembly systems.
A novel solid–liquid-core fiber-optic biosensor was fabricated for highly sensitive and selective detection of 4-chlorophenol in water. The sensor comprised horseradish peroxidase (HRP)-coated U-shaped liquid-core optical fiber (LCOF) and 4-chlorophenol permselective polymer membrane. The U-shaped LCOF was filled with ethanol suspension of SiO2 particles and the polymer membrane was composed of molecularly imprinted polymer, sulfonated polyethersulfone, and polysulfone. The morphology, composition, and surface luminous properties of the sensing region were examined. The effects of the diameter and content of SiO2 particles and temperature of 4-chlorophenol solutions on the sensitivity of the biosensors were investigated. Further, the sensitivity, selectivity, response time, and limit of detection (LOD) of the biosensors was investigated. In addition, the effects of fiber core materials on the light transmission in sensing region were investigated and a biosensor sensing model was established. The proposed sensor exhibited high selectivity for 4-chlorophenol with satisfactory sensitivity, LOD, and response time: -1.18 (µg/L)−1, 30 µg/L, and 400 s, respectively. The results are expected to aid in the development of methods for enhancing sensitivity of fiber-optic sensors and surface luminous intensity of optical fibers.
A cooperative Pd/Cu-catalyzed three-component cross-coupling reaction of alkynes, B2Pin2 and alkene-tethered aryl halides is reported. This reaction proceeds under mild conditions and shows broad substrate scope, providing a variety of heterocycles containing tetrasubstituted alkenylboronate moieties in synthetically useful yields with excellent chemoselectivity and regioselectivity. This transformation features the catalytic generation of β-borylalkenylcopper intermediates and their use in Pd-catalyzed Heck cyclization/cross-couplings. An enantioselective cascade cyclization/cross-coupling process has also been developed for the synthesis of enantiomerically enriched oxindole bearing a tetrasubstituted alkenylboronate moiety.
P2-type layered oxides are receiving significant interest due to their superior structure and intrinsic performances. There are strenuous attempts to balance the structure stability, phase transition as well as desirable electrochemical performances by inducing anion/cation ions, changing morphology, adjusting valence, etc. In this work, several same-period elements of Sc, Ti, V, Cr, Fe, Cu and Zn are doped into Na0.50Li0.08Mn0.60Co0.16Ni0.16O2 cathodes, which are manipulated by ions radii and valence state, further studied by operando X-ray powder diffraction patterns (XRD). As a result, the Cu2+ doped cathode performed higher rate capacities (as high as 86 mAh/g even at 10 C) and more stable structures (capacity retention of ~89.4% for 100 cycles), which owing to the synergistic effect among the tightened TMO2 layer, enlarged d-spacing, reduce OO electrostatic repulsion, ameliorate lattice distortion as well as mitigate ordering of Na+/vacancy.
α-Cyanostilbene (CS) based organic luminescent materials with efficient electrical conductivity, aggregation-induced enhanced emission, and controllable multi-colour emission properties, have been aroused wide attention by scientists over the past few years. Self-assembly of CS-motif in aqueous media refers to an environment-friendly method for preparing luminescent materials. However, it is still challenging to control the intrinsic hydrophobic properties of the organic components in aqueous media. In this study, an amphiphilic dicyanostilbene-functionalized thiophene (ACSTP) derivative was synthesized. Z-ACSTP was identified to dissolve in different organic solvents, accompanied with strong and tunable fluorescence emission. However, when Z-ACSTP was dispersed in water, it was self-assembled into nanofibers, and the fluorescence was red shifted, accompanied with sharp decrease of intensity compared with that in DMSO. Furthermore, Z-form of ACSTP to its E-form under 365 nm irradiation led to the morphology transformation from nanofibers to nanosheets. Notably, upon addition of water-soluble pillar[5]arene (WP5), the nanofibers were transformed into fluorescent hollow particles due to the host–guest interactions between the pyridinium group and WP5 and the obtained fluorescent particles can be further applied in living cell imaging.
High efficiency and low-cost catalyst-driven electrocatalytic CO2 reduction to CO production are of great significance for energy storage and development. The severe competitive hydrogen evolution reaction occurs at large negative potential window limits the achievement of the target product from CO2 at high efficiency. Here, we successfully prepared Cux/CdCO3 composite catalyst rich in interfaces, in which achieved high CO Faraday efficiency exceeded 90% in a wide potential window of 700 mV and highest value up to 97.9% at −0.90 V vs. RHE. The excellent performance can be ascribed to the positive contribution of Cux/CdCO3, which maintains a suitable high local pH value during electrochemical reduction, thus inhibiting the competitive hydrogen evolution reaction. Moreover, the compact structure between Cu and CdCO3 ensures fast electron transfer both inside catalysts and interface, thus speeding up the reaction kinetics of CO2 to CO conversion. Theoretically calculations further prove that the combination of Cu and CdCO3 provides the well-defined electronic structure for intermediates adsorption, significantly reducing the reaction barrier for the formation of CO. This work provides new insights into the design of efficient electrochemical CO2 reduction catalysts for inhibiting hydrogen evolution by adjusting the local pH effect.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
