Synthesis and Electronic Structure of a Crystalline Stack of MXene Sheets
Daniel L. Druffel, Matthew G. Lanetti, Jack D. Sundberg, Jacob T. Pawlik, Madeline S. Stark, Carrie L. Donley, Lauren M. McRae, Katie M. Scott, Scott C. Warren
Despite the interest in MXenes in the last decade, all of the MXenes reported have a random mixture of surface terminations (-O, -OH, -F). In addition, restacked films have turbostratic disorder and often contain ions, solvent, and other species in between their layers. Here we report Y2CF2, a layered crystal with a unit cell isostructural to a MXene, in which layers are capped only by fluoride anions. We directly synthesize the 3D crystal through a high-temperature solid-state reaction, which affords the 3D crystal in high yield and purity and ensures that only fluoride ions terminate the layers. We characterize the crystal structure and electronic properties using a combination of experimental and computational techniques. We find that relatively strong electrostatic interactions bind the layers together into a 3D crystal and that the lack of orbital overlap between layers gives rise to a description of Y2CF2 as slabs of MXene-like sheets electrically insulated from one another. Therefore, we consider Y2CF2 as a pure 3D crystalline stack of MXene-like sheets. In addition, Y2CF2 is the first transition metal carbide fluoride experimentally synthesized. We hope this work inspires further exploration of transition metal carbide fluorides, which are potentially a large and useful class of compositions.
The Potential of Ti$_3$C$_2$T$_X$ Nano-sheets (MXenes) for Nanoscale Solid Lubrication Revealed by Friction Force Microscopy
Ti $_3$ C $_2$ T $_X$纳米片（MXene）是一类新兴的二维材料，具有在从纳米到宏观的长度尺度上用于能量存储、催化和摩擦电应用的突出潜力。尽管对这类新材料的兴趣迅速增加，但它们的纳米级摩擦特性，特别是它们在纳米级上的固体润滑潜力，尚未得到详细研究。在这个简短的通信中，我们提出了第一个结果MXene的纳米级摩擦特性，在一个孤立的Ti $_3$ C $_2$ T $_x$纳米片上通过摩擦力显微镜沉积在二氧化硅衬底上获得的摩擦地图的形式。我们的实验表明，少层Ti $_3$ C $_2$ T $_x$纳米片确实在纳米级上充当固体润滑剂，减少二氧化硅基底上的摩擦，尽管不如少层石墨烯有效。本文报道的结果为进一步研究Ti $_3$ C $_2$ T $_X$（MXene）纳米片实现的纳米级固体润滑铺平了道路。
Surface Phase-Field-Crystal-Helfrich model for out-of-plane deformations in thin crystalline sheets with lattice mismatch
TU Dresden（德累斯顿工业大学）；Dresden Center for Computational Materials Science, TU Dresden（德累斯顿计算材料科学中心，德累斯顿工业大学）；Cluster of Excellence - Physics of Live, TU Dresden（卓越集群-生命物理学，德累斯顿工业大学）；Center for Systems Biology Dresden (CSBD)（德累斯顿系统生物学中心）
Ground state configuration of hydrogenated Biphenylene sheet: structure, stabilities, electronic and mechanical properties from first-principles calculations
Growth of Highly Conductive PtSe2 Films Controlled by Raman Metrics for High-Frequency Photodetectors and Optoelectronic Mixers at 1.55 μm
Thales Research & Technology（泰雷兹研究与技术）；Laboratoire de Physique de l'École Normale Supérieure（巴黎高等师范学校物理实验室）；CEA Grenoble（法国原子能和替代能源委员会格勒诺布尔中心）；Center for Nanoscience and Nanotechnology（纳米科学与技术中心）；Ecole Polytechnique（巴黎综合理工学院）
