中文摘要：

基于第一性原理方法计算,通过在g-C3N4中掺杂C、B和N原子，预测了四种元素均匀分布的B-C-N三元单层材料，除了B4-C3N4单层材料是一个具有1.18eV带隙的半导体，其余三种C-B-N三元单层材料都是金属材料，其中，B3C-C3N4是铁磁金金属，其净磁矩为0.57μB/原胞，可用于构建自旋电子器件材料，计算的形成能显示B-C-N三元体系具有较高的热稳定性。

英文摘要：

By using first principles calculations, four two-dimensional B-C-N ternary sheets with ordered and uniform element distribution are predicted based on the C, B, or N filled g-C3N4 sheet. These B-C-N ternary sheets are metallic except for B4-C3N4 monolayer, which is a semiconductor with an energy band gap of 1.18 eV. In particular, the BnC-C3N4 is a ferromagnetic metal with a net magnetic moment of 0.57 μB/cell, which can be used to develop metal-free spintronic device. The calculated formation energy indicates these B-C-N ternary sheets are highly thermal stable. It presents a new route to obtain uniform B-C-N ternary sheet for electronic and spintronic applications.