Covalent organic frameworks (COFs) are excellent platforms with tailored functionalities in photocatalysis. There are still challenges in increasing the photochemical performance of COFs. Therefore, we designed and prepared a series of COFs for photocatalytic hydrogen generation. Varying different ratios of βketoenamine to imine moieties in the linkages could differ the ordered structure, visible light harvesting, and bandgap. Overall, βketoenamine-linked COFs exhibited much better photocatalytic activity than those COFs having both β-ketoenamine and imine moieties on account of a nonquenched excited state and more favorable HOMO level in the photoinduced oxidation reaction from the former. Specifically, after in situ growth of β-ketoenamine-linked COFs onto NH 2 −Ti 3 C 2 T x MXene via covalent connection, the heterohybrid showed an obvious improvement in photocatalytic H 2 evolution because of strong covalent coupling, electrical conductivity, and efficient charge transfer. This integrated linkage evolution and covalent hybridization approach advances the development of COF-based photocatalysts.

Photocatalysts derived from semiconductor heterojunctions that harvest solar energy and catalyze reactions still suffer from low solar‐to‐hydrogen conversion efficiency. Now, MXene (Ti3C2TX) nanosheets (MNs) are used to support the in situ growth of ultrathin ZnIn2S4 nanosheets (UZNs), producing sandwich‐like hierarchical heterostructures (UZNs‐MNs‐UZNs) for efficient photocatalytic H2 evolution. Opportune lateral epitaxy of UZNs on the surface of MNs improves specific surface area, pore diameter, and hydrophilicity of the resulting materials, all of which could be beneficial to the photocatalytic activity. Owing to the Schottky junction and ultrathin 2D structures of UZNs and MNs, the heterostructures could effectively suppress photoexcited electron–hole recombination and boost photoexcited charge transfer and separation. The heterostructure photocatalyst exhibits improved photocatalytic H2 evolution performance (6.6 times higher than pristine ZnIn2S4) and excellent stability.

The tumor microenvironment (TME) with the characteristics of severe hypoxia, overexpressed glutathione (GSH), and high levels of hydrogen peroxide (H2O2) dramatically limits the antitumor efficiency by monotherapy. Herein, a novel TME‐modulated nanozyme employing tin ferrite (SnFe2O4, abbreviated as SFO) is presented for simultaneous photothermal therapy (PTT), photodynamic therapy (PDT), and chemodynamic therapy (CDT). The as‐fabricated SFO nanozyme demonstrates both catalase‐like and GSH peroxidase‐like activities. In the TME, the activation of H2O2 leads to the generation of hydroxyl radicals (•OH) in situ for CDT and the consumption of GSH to relieve antioxidant capability of the tumors. Meanwhile, the nanozyme can catalyze H2O2 to generate oxygen to meliorate the tumor hypoxia, which is beneficial to achieve better PDT. Furthermore, the SFO nanozyme irradiated with 808 nm laser displays a prominent phototherapeutic effect on account of the enhanced photothermal conversion efficiency (η = 42.3%) and highly toxic free radical production performance. This “all in one” nanozyme integrated with multiple treatment modalities, computed tomography, and magnetic resonance imaging properties, and persistent modulation of TME exhibits excellent tumor theranostic performance. This strategy may provide a new dimension for the design of other TME‐based anticancer strategies.

Organic solvent-exfoliated MoS2 nanosheets significantly improved the thermoelectric performance of flexible PEDOT:PSS thin films via the use of direct vacuum filtration.

No abstract

A flexible PEDOT:PSS thin-film achieves a high electrical conductivity (1500 S cm−1) and a high thermoelectric figure of merit (ZT ∼ 0.1) by a rapid direct dilution–filtration with common organic solvents.

Highly flexible PEDOT-based electronic textiles were successfully fabricated for wearable thermoelectric generators and strain sensors with high sensitivity and superior water durability.

Conducting polymer-based composite aerogel film is desired to be used as thermoelectric (TE) materials due to its good flexibility and ultralow thermal conductivity. Here, we proposed the simple freeze drying method to fabricate freestanding poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS)-based aerogel films without any crosslinker addition. The evolutions of morphology and TE performance were systemically investigated with various organic solvent addition. Furthermore, a series of the PEDOT:PSS/tellurium nanowires (Te-NWs) composite aerogel films was prepared, and the relationship between the structure and the charge-transport mechanism of the binary complex system was explored based on series and parallel models. Finally, an efficient dimethyl sulfoxide-vapor annealing was employed to further optimize the TE performance of PEDOT:PSS/ Te-NWs composite aerogel films. The ZT value was estimated to be 2.0 × 10 −2 at room temperature. On the basis of the flexibility and highly enhanced TE performance, a prototype TE generator consisting of p-type PEDOT:PSS/Te-NWs aerogel films and n-type carbon nanotube fibers as legs has been fabricated with an acceptable output power of 1.28 μW at a temperature gradient of 60 K, which could be potentially applied in wearable electronics.