Screening of low-friction two-dimensional materials from highthroughput calculations using lubricating figure of merit

Two-dimensional materials are excellent lubricants with inherent advantages.However,superlubricity has been reported for only a few of these materials.Unfortunately,other promising two-dimentional(2D)materials with different physical properties cannot be discovered or applied in production;thus,energy consumption can be greatly reduced.Here,we carry out high-throughput calculations for 1,4752D materials and screen for low-friction materials.To set a standard,we propose,for the first time,a geometry-independent lubricating figure of merit based on the conditions for stick-slip transition and our theory of Moiréfriction.For the efficient calculation of this figure of merit,an innovative approach was developed based on an improved registry index model.Through calculations,340 materials were found to have a figure of merit lower than 10−3.Eventually,a small set of 21 materials with a figure of merit lower than 10−4 were screened out.These materials can provide diverse choices for various applications.In addition,the efficient computational approach demonstrated in this work can be used to study other stacking-dependent properties.

A High-Performance MoS_(2)-Based Visible-Near-Infrared Photodetector from Gateless Photogating Effect Induced by Nickel Nanoparticles

Recent advancements in two-dimensional materials have shown huge potential for optoelectronic applications.It is challenging to achieve highly effective and sensitive broadband photodetection based on MoS_(2)devices.Defect engineering,such as introducing vacancies,can narrow the bandgap and boost the separation of photogenerated carriers by defect states but leads to a slow response speed.Herein,we propose a nickel nanoparticle-induced gateless photogating effect with a unique energy band structure to enable the application of defect engineering and achieve high optoelectronic performance.The device based on Ni nanoparticle-decorated MoS_(2)with S vacancies exhibited high responsivities of 106.21 and 1.38 A W^(-1)and detectivities of 1.9×10^(12)and 8.9×10^(9)Jones under 532 and 980 nm illumination(visible to near infrared),respectively,with highly accelerated response speed.This strategy provides new insight into optimizing defect engineering to design high-performance optoelectronic devices capable of broadband photodetection.

High-Throughput Calculation of Interlayer van der Waals Forces Validated with Experimental Measurements

Interlayer van der Waals interactions play an important role in two-dimensional(2D)materials on various occasions.The interlayer binding force is often directly measured and is considered more closely related to the exfoliation condition.However,a binding force database from accurate theoretical calculations does not yet exist.In this work,the critical interlayer binding force and energy are directly calculated for 2302D materials,which exhibit divergent trends.A linear relationship that links the two quantities with the equilibrium interlayer distance is found and checked.Experiments are carried out for three different materials using atomic force microscopy.The measured forces show a consistent trend with the calculated results,and the estimated binding strengths are of the same order of magnitude as the predicted values.Our work can provide a reliable reference for interlayer adhesion studies and help establish accurate models of exfoliation processes.