Two-dimensional materials for high density, safe and robust metal anodes batteries.

With a high specific capacity and low electrochemical potentials, metal anode batteries that use lithium, sodium and zinc metal anodes, have gained great research interest in recent years, as a potential candidate for high-energy-density storage systems. However, the uncontainable dendrite growth during the repeated charging process, deteriorates the battery performance, reduces the battery life and more importantly, raises safety concerns. With their unique properties, two-dimensional (2D) materials, can be used to modify various components in metal batteries, eventually mitigating the dendrite growth, enhancing the cycling stability and rate capability, thus leading to safe and robust metal anodes.

Machine Learning-Aided Design of Gold Core-Shell Nanocatalysts toward Enhanced and Selective Photooxygenation.

We demonstrate the use of the machine learning (ML) tools to rapidly and accurately predict the electric field as a guide for designing core-shell Au-silica nanoparticles to enhance O sensitization and selectivity of organic synthesis. Based on the feature importance analysis, obtained from a deep neural network algorithm, we found a general and linear dependent descriptor (θ ∝ , where , , and are the shape constant, size of metal nanoparticles, and distance from the metal surface) for the electric field around the core-shell plasmonic nanoparticle. Directed by the new descriptor, we synthesized gold-silica nanoparticles and validated their plasmonic intensity using scanning transmission electron microscopy-electron energy loss spectroscopy (STEM-EELS) mapping.

Band Alignment Engineering by Twist Angle and Composition Modulation for Heterobilayer.

Atomically thin monolayer semiconducting transition metal dichalcogenides (TMDs), exhibiting direct band gap and strong light-matter interaction, are promising for optoelectronic devices. However, an efficient band alignment engineering method is required to further broaden their practical applications as versatile optoelectronics. In this work, the band alignment of two vertically stacked monolayer TMDs using the chemical vapor deposition (CVD) method is effectively tuned by two strategies: 1) formulating the compositions of MoS Se alloys, and 2) varying the twist angles of the stacked heterobilayer structures.

Conductive Hydrogel Conduits with Growth Factor Gradients for Peripheral Nerve Repair in Diabetics with Non-Suture Tape.

Diabetic patients suffer from peripheral nerve injury with slow and incomplete regeneration owing to hyperglycemia and microvascular complications. This study develops a graphene-based nerve guidance conduit by incorporating natural double network hydrogel and a neurotrophic concentration gradient with non-invasive treatment for diabetics. GelMA/silk fibroin double network hydrogel plays quadruple roles for rapid setting/curing, suitable mechanical supporting, good biocompatibility, and sustainable growth factor delivery.

Rational Control on Quantum Emitter Formation in Carbon-Doped Monolayer Hexagonal Boron Nitride.

Single-photon emitters (SPEs) in hexagonal boron nitride (hBN) are promising candidates for quantum light generation. Despite this, techniques to control the formation of hBN SPEs down to the monolayer limit are yet to be demonstrated. Recent experimental and theoretical investigations have suggested that the visible wavelength single-photon emitters in hBN originate from carbon-related defects.

Aligned Graphene Mesh-Supported Double Network Natural Hydrogel Conduit Loaded with Netrin-1 for Peripheral Nerve Regeneration.

The gold standard treatment for peripheral nerve injuries (PNIs) is the autologous graft, while it is associated with the shortage of donors and results in major complications. In the present study, we engineer a graphene mesh-supported double-network (DN) hydrogel scaffold, loaded with netrin-1. Natural alginate and gelatin-methacryloyl entangled hydrogel that is synthesized via fast exchange of ions and ultraviolet irradiation provide proper mechanical strength and excellent biocompatibility and can also serve as a reservoir for netrin-1.

Selenium Edge as a Selective Anchoring Site for Lithium-Sulfur Batteries with MoSe/Graphene-Based Cathodes.

For lithium-sulfur batteries (LSBs), the dissolution of lithium polysulfide and the consequent "shuttle effect" remain major obstacles for their practical applications. In this study, we designed a new cathode material comprising MoSe/graphene to selectively adsorb polysulfides on the selenium edges and thus to mitigate their dissolution. More specifically, few-layered MoSe was first grown on nitrogen-doped reduced graphene oxide (N-rGO) using the chemical vapor deposition method and then infiltrated with sulfur as the cathode for LSBs.

Methacrylated gelatin-embedded fabrication of 3D graphene-supported CoO nanoparticles for water splitting.

We developed a general platform for the fabrication of transition metal oxide nanoparticles supported by a graphene foam (GF) by first coating it with a methacrylated gelatin (GelMA) hydrogel, which served as a 3D matrix for nanoparticle dispersion. The engineered GelMA/GF matrix was hydrophilic with good mechanical strength and high conductivity, therefore providing a good platform for the dispersion of a variety of metal/oxide precursors. Due to this platform, well-dispersed Co3O4 nanoparticles with the smallest size of 3 nm assembled on the nitrogen-doped graphene foam (Co3O4/NGF).

In situ formed nanoparticle-assisted growth of large-size single crystalline h-BN on copper.

h-BN is a widely used ultrathin insulator that can be synthesized in a controllable manner by chemical vapor deposition, similar to the growth of graphene. However, it is challenging to grow large-size single crystalline h-BN because of the ambiguous understanding of its growth mechanism. In this study, we propose a novel in situ formed nanoparticle-assisted growth strategy for large-size single crystalline h-BN growth on conventional polycrystalline copper.

Stacking Modes-Induced Chemical Reactivity Differences on Chemical Vapor Deposition-Grown Trilayer Graphene.

Trilayer graphene (TLG) synthesized by chemical vapor deposition (CVD), in particular the twisted TLG, exhibits sophisticated electronic structures that depend on their stacking modes. Here, we computationally and experimentally demonstrate the chemical reactivity differences of CVD-TLG induced by the stacking modes and corroborated by a photoexcited phenyl-grafting reaction. The experimental results show that the ABA stacking TLGs have the most inert chemical property, yet 30°-30° stacking twisted TLGs are the most active.