Growth of non-layered 2D transition metal nitrides enabled by transient chloride templates

2D transition metal nitrides (TMNs) have attracted significant attention due to their magnetic, electrical, and chemical properties at atomic thickness. However, the synthesis of 2D TMNs is still challenging, due to their strong isotropic metal-nitrogen bonding networks. Here, we report a universal synthesis of non-layered 2D TMN family by using corresponding metastable metal chlorides as transient templates. This approach takes advantage of the layered structures and low conversion energy barriers of transition metal chlorides (TMCls) to grow 2D TMNs. Fifteen types of 2D TMNs and their alloys were synthesized, demonstrating the versatility of this method. The 2D TMN family exhibits tunable magnetic characteristics ranging from antiferromagnet to hard magnet, which can be modulated by their composition. This work overcomes previous synthesis limitations, thus offering a pathway to explore fundamental properties of 2D TMNs and accelerate their applications.