High‐pressure Synthesis of Cobalt Polynitrides - Unveiling Intriguing Crystal Structures and Nitridation Behavior
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2024-03-25 |
| Journal | Chemistry - A European Journal |
| Authors | Huawei Chen, Maxim Bykov, Iskander G. Batyrev, Lukas Brüning, Elena Bykova |
| Institutions | Argonne National Laboratory, University of Cologne |
| Citations | 6 |
Abstract
Section titled “Abstract”Abstract In this study, we conduct extensive high‐pressure experiments to investigate phase stability in the cobalt‐nitrogen system. Through a combination of synthesis in a laser‐heated diamond anvil cell, first‐principles calculations, Raman spectroscopy, and single‐crystal X‐ray diffraction, we establish the stability fields of known high‐pressure phases, hexagonal NiAs‐type CoN, and marcasite‐type CoN 2 within the pressure range of 50-90 GPa. We synthesize and characterize previously unknown nitrides, Co 3 N 2 , Pnma ‐CoN and two polynitrides, CoN 3 and CoN 5 , within the pressure range of 90-120 GPa. Both polynitrides exhibit novel types of polymeric nitrogen chains and networks. CoN 3 feature branched‐type nitrogen trimers (N 3 ) and CoN 5 show π‐bonded nitrogen chain. As the nitrogen content in the cobalt nitride increases, the CoN 6 polyhedral frameworks transit from face‐sharing (in CoN) to edge‐sharing (in CoN 2 and CoN 3 ), and finally to isolated (in CoN 5 ). Our study provides insights into the intricate interplay between structure evolution, bonding arrangements, and high‐pressure synthesis in polynitrides, expanding the knowledge for the development of advanced energy materials