Computational insights of defects in layered materials for energy sustainability technologies

We present work in the Wang Materials Group (https://wangmaterialgroup.com) in understanding and harnessing defects in materials for energy sustainability applications. Here, we present on two case studies of defects in next-generation memory/storage applications and electrocatalysts. In the first case study, we look to memristors, which are an emerging memory technology that can help meet the capacity and energy efficiency demands needed for the era of AI. Non-volatile resistive switching (NVRS) has been broadly observed in various 2D materials. We consider one particular mechanism of NVRS based on the formation and dissolution of point defect complexes. Major challenges to realizing low-dimensional material as memristors are identifying the optimal material in a sea of choices with favorable NVRS characteristics and the lack of a physical model for describing the switching mechanism. This talk will present our efforts in tackling these challenges- namely in searching for point defects that induce NVRS and in a case study of Au in MoS₂ on the physical origins of resistive switching. In the second case study, we turn to the study of electrocatalysts for realizing a clean hydrogen economy. The (oxy)hydroxides are significant as electrocatalysts that electrochemically form on many pre-catalyst surfaces in the amorphous state. We will discuss our efforts in understanding the impact of defects and related structural disorder on electrocatalytic activity.