Highly Transparent Low Resistance ZnO/Ag Nanowire/ZnO Composite Electrode for Thin Film Solar Cells

We present an indium-free transparent conducting composite electrode composed of silver nanowires (AgNWs) and ZnO bilayers. The AgNWs form a random percolating network embedded between the ZnO layers. The unique structural features of our ZnO/AgNW/ZnO multilayered composite allow for a novel transparent conducting electrode with unprecedented excellent thermal stability (∼375 °C), adhesiveness, and flexibility as well as high electrical conductivity (∼8.0 Ω/sq) and good optical transparency (>91% at 550 nm). Cu(In,Ga)(S,Se)₂ (CIGSSe) thin film solar cells incorporating this composite electrode exhibited a 20% increase of the power conversion efficiency compared to a conventional sputtered indium tin oxide-based CIGSSe solar cell. The ZnO/AgNW/ZnO composite structure enables effective light transmission and current collection as well as a reduced leakage current, all of which lead to better cell performance

The chromodomain-containing histone acetyltransferase TIP60 acts as a code reader, recognizing the epigenetic codes for initiating transcription

<div><p>TIP60 can act as a transcriptional activator or a repressor depending on the cellular context. However, little is known about the role of the chromodomain in the functional regulation of TIP60. In this study, we found that TIP60 interacted with H3K4me3 in response to TNF-α signaling. TIP60 bound to H3K4me3 at the promoters of the NF-κB target genes <i>IL6</i> and <i>IL8</i>. Unlike the wild-type protein, a TIP60 chromodomain mutant did not localize to chromatin regions. Because TIP60 binds to histones with specific modifications and transcriptional regulators, we used a histone peptide assay to identify histone codes recognized by TIP60. TIP60 preferentially interacted with methylated or acetylated histone H3 and H4 peptides. Phosphorylation near a lysine residue significantly reduced the affinity of TIP60 for the modified histone peptides. Our findings suggest that TIP60 acts as a functional link between the histone code and transcriptional regulators.</p></div

Uniform Graphene Quantum Dots Patterned from Self-Assembled Silica Nanodots

Graphene dots precisely controlled in size are interesting in nanoelectronics due to their quantum optical and electrical properties. However, most graphene quantum dot (GQD) research so far has been performed based on flake-type graphene reduced from graphene oxides. Consequently, it is extremely difficult to isolate the size effect of GQDs from the measured optical properties. Here, we report the size-controlled fabrication of uniform GQDs using self-assembled block copolymer (BCP) as an etch mask on graphene films grown by chemical vapor deposition (CVD). Electron microscope images show that as-prepared GQDs are composed of mono- or bilayer graphene with diameters of 10 and 20 nm, corresponding to the size of BCP nanospheres. In the measured photoluminescence (PL) spectra, the emission peak of the GQDs on the SiO₂ substrate is shown to be at ∼395 nm. The fabrication of GQDs was supported by the analysis of the Raman spectra and the observation of PL spectra after each fabrication step. Additionally, oxygen content in the GQDs is rationally controlled by additional air plasma treatment, which reveals the effect of oxygen content to the PL property