A facile and effective hydrothermal method for the fabrication of the Ag 3 PO 4 -graphene (Ag 3 PO 4 -GR) visible light photocatalyst has been developed to improve the photocatalytic performance and stability of Ag 3 PO 4 , and also to reduce the high cost of Ag 3 PO 4 for practical uses. The size and morphology of Ag 3 PO 4 particles could be tailored by the electrostatically driven assembly of Ag + on graphene oxide (GO) sheets and by the controlled growth of Ag 3 PO 4 particles on the GO surface. The generation of Ag 3 PO 4 and the transformation of GO to GR can be achieved simultaneously in the hydrothermal process. The improved photocatalytic activity of Ag 3 PO 4 -GR composites under visible light irradiation is attributed to high-surface-area GR sheets, enhanced absorption of organic dyes, and more efficient separation of photogenerated electron−hole pairs. The transfer of photogenerated electrons from the surface of Ag 3 PO 4 to GR sheets also reduces the possibility of decomposing Ag + to metallic Ag, suggesting an improved stability of recyclable Ag 3 PO 4 -GR composite photocatalyst. Moreover, with the advances in the large-scale production of high-quality GO, the use of GO as the starting material can also reduce the cost for the synthesis of Ag 3 PO 4 -based photocatalysts without weakening their photocatalytic activities.

The fabrication of low-density and compressible polymer/graphene composite (PGC) foams for adjustable electromagnetic interference (EMI) shielding remains a daunting challenge. Herein, ultralightweight and compressible PGC foams have been developed by simple solution dip-coating of graphene on commercial polyurethane (PU) sponges with highly porous network structure. The resultant PU/graphene (PUG) foams had a density as low as ∼0.027-0.030 g/cm(3) and possessed good comprehensive EMI shielding performance together with an absorption-dominant mechanism, possibly due to both conductive dissipation and multiple reflections and scattering of EM waves by the inside 3D conductive graphene network. Moreover, by taking advantage of their remarkable compressibility, the shielding performance of the PUG foams could be simply adjusted through a simple mechanical compression, showing promise for adjustable EMI shielding. We believe that the strategy for fabricating PGC foams through a simple dip-coating method could potentially promote the large-scale production of lightweight foam materials for EMI shielding.

A metal-free organic dye-sensitized solar cell attains 13% power conversion efficiency under AM1.5G full sunlight.

DNA hybridization can finely regulate the intrinsic glucose oxidase like catalytic activity of AuNPs owing to the marked difference in adsorption of single‐ and double‐stranded DNA on its surface. A sensing strategy for DNA and microRNA is presented; in a different approach, this DNA‐regulated AuNP catalysis was coupled with AuNP‐mediated seed growth, which was monitored in real time and at a single‐nanoparticle level.

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A series of lead‐free double perovskite nanocrystals (NCs) Cs2AgSb1−yBiyX6 (X: Br, Cl; 0≤y≤1) is synthesized. In particular, the Cs2AgSbBr6 NCs is a new double perovskite material that has not been reported for the bulk form. Mixed Ag–Sb/Bi NCs exhibit enhanced stability in colloidal solution compared to Ag–Bi or Ag–Sb NCs. Femtosecond transient absorption studies indicate the presence of two prominent fast trapping processes in the charge‐carrier relaxation. The two fast trapping processes are dominated by intrinsic self‐trapping (ca. 1–2 ps) arising from giant exciton–phonon coupling and surface‐defect trapping (ca. 50–100 ps). Slow hot‐carrier relaxation is observed at high pump fluence, and the possible mechanisms for the slow hot‐carrier relaxation are also discussed.

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Tremendous progress has recently been achieved in the field of perovskite solar cells (PSCs) as evidenced by impressive power conversion efficiencies (PCEs); but the high PCEs of >20% in PSCs has so far been mostly achieved by using the hole transport material (HTM) spiro-OMeTAD; however, the relatively low conductivity and high cost of spiro-OMeTAD significantly limit its potential use in large-scale applications. In this work, two new organic molecules with spiro[fluorene-9,9′-xanthene] (SFX)-based pendant groups, X26 and X36, have been developed as HTMs. Both X26 and X36 present facile syntheses with high yields. It is found that the introduced SFX pendant groups in triphenylaminebased molecules show significant influence on the conductivity, energy levels, and thin-film surface morphology. The use of X26 as HTM in PSCs yields a remarkable PCE of 20.2%. In addition, the X26-based devices show impressive stability maintaining a high PCE of 18.8% after 5 months of aging in controlled (20%) humidity in the dark.