Nickel Nitride Particles Supported on 2D Activated Graphene–Black Phosphorus Heterostructure: An Efficient Electrocatalyst for the Oxygen Evolution Reaction

Hydrogen is regarded as the most promising green clean energy in the 21st century. Developing the highly efficient and low‐cost electrocatalysts for oxygen evolution reaction (OER) is of great concern for the hydrogen industry. In the water electrolyzed reaction, the overpotential and the kinetics are the main hurdles for OER. Therefore, an efficient and durable oxygen evolution reaction electrocatalyst is required. In this study, an activated graphene (AG)–black phosphorus (BP) nanosheets hybrid is fabricated for supporting Ni3N particles (Ni3N/BP‐AG) in the application of OER. The Ni3N particles are combined with the BP‐AG heterostructure via facile mechanical ball milling under argon protection. The synthesized Ni3N/BP‐AG shows excellent catalytic performance toward the OER, demanding the overpotential of 233 mV for a current density of 10 mA cm−2 with a Tafel slope of 42 mV dec−1. The Ni3N/BP‐AG catalysts also show remarkable stability with a retention rate of the current density of about 86.4% after measuring for 10 000 s in potentiostatic mode.A black phosphorus (BP)–activated graphene (AG) heterostructure is designed for supporting nickel nitride (Ni3N) to enhance the performance of oxygen evolution reaction (OER). The Ni3N/BP‐AG exhibits excellent electrocatalytic performance toward OER with low overpotential and small Tafel slope. It also shows remarkable stability with a retention rate of ≈86.4% OER activity after 10 000 s.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/152804/1/smll201901530.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/152804/2/smll201901530_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/152804/3/smll201901530-sup-0001-S1.pd

A Generic Multi-Player Transformation Algorithm for Solving Large-Scale Zero-Sum Extensive-Form Adversarial Team Games

Many recent practical and theoretical breakthroughs focus on adversarial team multi-player games (ATMGs) in ex ante correlation scenarios. In this setting, team members are allowed to coordinate their strategies only before the game starts. Although there existing algorithms for solving extensive-form ATMGs, the size of the game tree generated by the previous algorithms grows exponentially with the number of players. Therefore, how to deal with large-scale zero-sum extensive-form ATMGs problems close to the real world is still a significant challenge. In this paper, we propose a generic multi-player transformation algorithm, which can transform any multi-player game tree satisfying the definition of AMTGs into a 2-player game tree, such that finding a team-maxmin equilibrium with correlation (TMECor) in large-scale ATMGs can be transformed into solving NE in 2-player games. To achieve this goal, we first introduce a new structure named private information pre-branch, which consists of a temporary chance node and coordinator nodes and aims to make decisions for all potential private information on behalf of the team members. We also show theoretically that NE in the transformed 2-player game is equivalent TMECor in the original multi-player game. This work significantly reduces the growth of action space and nodes from exponential to constant level. This enables our work to outperform all the previous state-of-the-art algorithms in finding a TMECor, with 182.89, 168.47, 694.44, and 233.98 significant improvements in the different Kuhn Poker and Leduc Poker cases (21K3, 21K4, 21K6 and 21L33). In addition, this work first practically solves the ATMGs in a 5-player case which cannot be conducted by existing algorithms.Comment: 9 pages, 5 figures, NIPS 202

Incontinentia Pigmenti: Case Report

Incontinentia pigmenti (IP) or Bloch-Sulzberger syndrome, is a rare X linked dominant disorder with characteristic skin, hair, eye, dental and neurological abnormalities mostly affecting females. We reported two cases of newborn female children exhibiting characteristic cutaneous and neurological findings with one year follow-up.</p

Formamide deionized accelerates the somatic embryogenesis of Cunninghamia lanceolata

Aim of the study: To improve the efficiency of the somatic embryogenesis (SE) in Cunninghamia lanceolata. Area of the study: The study was conducted at Nanjing Forestry University (Nanjing, China). Material and methods: Immature cones of C. lanceolata, genotype 01A1 which was planted in Yangkou State-owned Forest Farm (Fujian, China), were used to induced callus. These calli were used to induce SE, concentration gradients of 0 g/L, 0.01134 g/L, 0.1134 g/L, 1.1134 g/L and 11.34 g/L of FD was added, to explore the optimal concentration for promoting SE of C. lanceolata. Main results: Low concentration of FD promoted the maturation of somatic embryos, while high concentration of FD lead to browning of embryogenic callus. The seedling rate and rooting number of seedlings induced by different concentrations of FD were significantly different. Research highlights: This study may aid in the rapid maturation of C. lanceolata somatic embryos and is useful for accelerated C. lanceolata breeding. Keywords: C. lanceolata; Formamide Deionized; Somatic embryogenesis; Seedling rate. Abbreviations used: FD (Formamide Deionized), FD0 (the concentration of 0 g/L FD), FD0.01134 (the concentration of 0.01134 g/L FD), FD0.1134 (the concentration of 0.1134 g/L FD), FD1.134 (the concentration of 1.134 g/L FD), FD11.34 (the concentration of 11.34 g/L FD)

Electronic Structure, Surface Doping, and Optical Response in Epitaxial WSe2 Thin Films

High quality WSe2 films have been grown on bilayer graphene (BLG) with layer-by-layer control of thickness using molecular beam epitaxy (MBE). The combination of angle-resolved photoemission (ARPES), scanning tunneling microscopy/spectroscopy (STM/STS), and optical absorption measurements reveal the atomic and electronic structures evolution and optical response of WSe2/BLG. We observe that a bilayer of WSe2 is a direct bandgap semiconductor, when integrated in a BLG-based heterostructure, thus shifting the direct-indirect band gap crossover to trilayer WSe2. In the monolayer limit, WSe2 shows a spin-splitting of 475 meV in the valence band at the K point, the largest value observed among all the MX2 (M = Mo, W; X = S, Se) materials. The exciton binding energy of monolayer-WSe2/BLG is found to be 0.21 eV, a value that is orders of magnitude larger than that of conventional 3D semiconductors, yet small as compared to other 2D transition metal dichalcogennides (TMDCs) semiconductors. Finally, our finding regarding the overall modification of the electronic structure by an alkali metal surface electron doping opens a route to further control the electronic properties of TMDCs

Topology hierarchy of transition metal dichalcogenides built from quantum spin Hall layers

The evolution of the physical properties of two-dimensional material from monolayer limit to the bulk reveals unique consequences from dimension confinement and provides a distinct tuning knob for applications. Monolayer 1T'-phase transition metal dichalcogenides (1T'-TMDs) with ubiquitous quantum spin Hall (QSH) states are ideal two-dimensional building blocks of various three-dimensional topological phases. However, the stacking geometry was previously limited to the bulk 1T'-WTe2 type. Here, we introduce the novel 2M-TMDs consisting of translationally stacked 1T'-monolayers as promising material platforms with tunable inverted bandgaps and interlayer coupling. By performing advanced polarization-dependent angle-resolved photoemission spectroscopy as well as first-principles calculations on the electronic structure of 2M-TMDs, we revealed a topology hierarchy: 2M-WSe2, MoS2, and MoSe2 are weak topological insulators (WTIs), whereas 2M-WS2 is a strong topological insulator (STI). Further demonstration of topological phase transitions by tunning interlayer distance indicates that band inversion amplitude and interlayer coupling jointly determine different topological states in 2M-TMDs. We propose that 2M-TMDs are parent compounds of various exotic phases including topological superconductors and promise great application potentials in quantum electronics due to their flexibility in patterning with two-dimensional materials