A self-assembled spongy-like (S) ultralight (ρ ≈ 140 mg cm −3 ) aerogel was fabricated through polypyrrole (PPy) and reduced graphene oxide (RGO). Firstly, the dispersed graphene oxide (GO) were locked homogeneously in those chains formed by the gelation of PPy. Then a hydrothermal process was employed to reduce GO to RGO. With a trace content of RGO (0.43 wt% in aerogel), the electromagnetic absorption (EA) performance had been significant improved. Only with a very low filler loading (10 wt%), the S-PPy/RGO aerogel based composite could reach an effective EA bandwidth (below − 10 dB) of 6.76 GHz, and the highest reflection coefficient reached − 54.4 dB at 12.76 GHz. It was demonstrated that this aerogel material can be considered as an effective route to design a light weight and high performance EA material. Furthermore, the 3D-PPy/RGO aerogel also showed a suitable pollution treatment performance with different solvents and dyes. materials, such as intercalated graphite, 14 carbon nanotubes (CNTs), 15,16 porous carbon, 17,18 carbon nanopowders, 19 carbon fibers, 20 graphene, 21 and reduced graphene oxide (RGO). 22 Benefit from the nano-structure, these above mentioned materials can reach an ideal EA performance with a fitting filler loading ratio in composites. However, metal oxide or sulfide based EA composites can't overcome high filler loading ratio, even reach 70.0 wt%; 5 pure carbon materials based EA composites can't get a sufficient broad effective EA bandwidth (below − 10 dB) with low matching thickness, though they give low loading ratio in composites (less than 20.0 wt%).Taking RGO for instance, it is a kind of two dimensional (2D) carbon material that can be synthesized from graphene oxide (GO) using chemical, 23 thermal, 24 optical, 25,26 and hydrothermal 27 methods. Dielectric loss and the low density of RGO enable it to be used as EA material. With a suitable preparation process, pure RGO based composite can display an effective EA bandwidth of 4.32 GHz with a thickness of 4 mm. 22 The development of functional RGO modified with other nanoparticles also represents an important advance to improve EA performance both in width and intensity, meanwhile reduce the thickness of the composites, such as Fe Furthermore, core-shell structures, for example, Fe 3 O 4 @ZnO, 44 SiO 2 @Fe 3 O 4 , 45 and Fe 3 O 4 @Fe, 46 can also improve the EA performance of RGO.Besides the above mentioned EA materials, recently, the intrinsically conducting polymers (ICPs) with low densities, such as PEDOT, PANi and polypyrrole (PPy), are also great interest as EA materials and EA performance are closely related to the structure. 46 However, composite only loaded with single ICP is not enough to produce sufficient electric loss, which limits its application in broadband absorber. Although the EA performance can be improved through hybridizing other semiconductors or RGO is only trace content (0.43 wt%) in aerogel to match the impedance with air, which makes this aerogel cheap enough for large-scaled use. Furthermore, the S-PP...

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.

Heteroatom doping is one of the most effective routes to adjust the physicochemical and optical properties of carbon dots (CDs). However, fluorine (F) doped CDs have been barely achieved. In this work, a F-doping strategy was proposed and adopted to modulate optical properties of CDs. A kind of F-doped CDs was synthesized by a solvothermal process using aromatic F bearing moiety as the F source and shows much longer maximum emissions (up to 600 nm, red fluorescence) than that of undoped CDs, indicating a large emission red-shift effect by F-doping. In addition, the F-doped CDs have remarkable water-solubility, high biocompatibility, as well as excellent stability even under broad pH range, ionic strengths, and light illumination and thus can be used as a novel probe for the highly efficient cell imaging of various normal cells and cancer cells. The F-doped CDs can selectively bind to Ag + . It therefore makes the F-doped CDs be a highly sensitive probe for the detection of Ag + under both aqueous solution and various biological systems. The huge potential of this F-doping strategy is indicated in the rational design of high-performance CDs, as well as in applications of clinical diagnosis and ion detection.

First report on the excellent electromagnetic absorption and electromagnetic interference shielding performances of helical conducting polymer nano-structures.

Carbon dots (CDs) focus great attention in a broad range of adhibitions because of their excellent optical properties and high biocompatibility and property adjustability. However, the developed CDs have rarely been used as effective gene vectors until now. In this work, we devised and synthesized novel fluorine-doped cationic CDs (FCDs) using tetrafluoroterephthalic acid as a fluorine source and using branched polyethylenimine to furnish positive charge sites. The FCDs achieve dramatic positive EGFP and luciferase gene transfection efficiency as well as low cytotoxicity in commonly used cell lines at a low weight ratio, even in primary and stem cells. It is worth pointing out that the FCDs possess superior efficiency and biocompatibility, compared to some widely used commercial reagents such as 25 kDa polyethylenimine and Lipofectamine 2000. In addition, the FCDs show excellent efficient transfection even at high serum concentration and low DNA dose, indicating potential practical applications.

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A facile self-assembled polymerization method has been used to form pyrrole to an ultralight three-dimensional (3D) polypyrrole (PPy) aerogel. It exhibits an effective electromagnetic absorption (EA) bandwidth (deeper than −10 dB), which was characterized as 6.2 GHz when the filler loading is only 7 wt. % in paraffin based composite. This 3D-PPy aerogel can be considered as a light weight, low adjunction, thin thickness, and high performance EA material.

We herein report mussel-inspired polydopamine nanofilms as light-harvesting interfaces for heterogeneous palladium catalyzed coupling reactions under irradiation from visible light.