DJL

Improved cellular selectivity for nucleoli staining was achieved by simple chemical modification of carbon dots (C-dots) synthesized from waste carbon sources such as cow manure (or from glucose). The C-dots were characterized and functionalized (amine-passivated) with ethylenediamine, affording amide bonds that resulted in bright green fluorescence. The new modified C-dots were successfully applied as selective live-cell fluorescence imaging probes with impressive subcellular selectivity and the ability to selectively stain nucleoli in breast cancer cell lineages (MCF-7). The C-dots were also tested in four other cellular models and showed the same cellular selection in live-cell imaging experiments.

Cow dots: Improved cellular selectivity for nucleoli staining was achieved by simple amine passivation of carbon dots (C-dots) synthesized from cow manure. The modified C-dots were successfully applied as selective live-cell fluorescence imaging probes with impressive subcellular selectivity and the ability to selectively stain nucleoli in breast cancer and other cell lines.

In article number 1401539, Doojin Vak and co-workers describe a new way of developing and sharing processes for the fabrication of solution-processed solar cells by using a modified 3D printer. The printer is controlled by a text-based standard digital protocol that can be used in any compatible printers. The results suggest a new paradigm of sharing processes between machines, labs, and eventually factories.

Phosphorene, an emerging elemental 2D direct band gap semiconductor with fascinating structural and electronic properties distinctively different from other 2D materials such as graphene and MoS₂, is promising for novel nanoelectronic and optoelectronic applications. Phonons, as one of the most important collective excitations, are at the heart of the device performance, as their interactions with electrons and photons govern the carrier mobility and light-emitting efficiency of the material. Here, through a detailed first-principles study, it is demonstrated that monolayer phosphorene exhibits a giant phononic anisotropy, and remarkably, this anisotropy is squarely opposite to its electronic counterpart and can be tuned effectively by strain engineering. By sampling the whole Brillouin zone for the monolayer phosphorene, several “hidden” directions are found, along which small-momentum phonons are “frozen” with strain and possess the smallest degree of anharmonicity. Unexpectedly, these “hidden” directions are intrinsically different from the usually-studied armchair and zigzag directions. Light is also shed on the anisotropy of interlayer coupling of few-layer phosphorene by examining the rigid-layer vibrations. These highly anisotropic and strain-tunable characteristics of phosphorene offer new possibilities for its applications in thermal management, thermoelectronics, nanoelectronics, and phononics.

Phosphorene, with a honeycomb lattice as graphene but puckered with ridge and accordion atomic profiles along the zigzag and armchair directions, shows a strong phonon anisotropy, and significant orientation-dependent interlayer coupling. Simulations reveal a more pronounced interlayer interaction and thermal leakage normal to the layer direction; accordingly, a different strategy is needed for thermal management of phosphorene devices.

Solution-processed organohalide perov­skite photodiodes that have performance metrics matching silicon, but are infrared-blind are reported. The perovskite photodiodes operate in the visible band, have low dark current and noise, high specific detectivity, large linear dynamic range, and fast temporal response. Their properties make them promising candidates for imaging applications.