Synthesis, Crystal Structures, Mechanical Properties, and Formation Mechanisms of Cubic Nitrides

Zhou, Xuefeng1,2,3; Gu, Chao2,3; Song, Guozhu2,3; Ma, Dejiang2; Fang, Leiming4; Zhou, Chunyin5; Zhao, Yusheng2,3; Liang, Yongcheng6,7; Wang, Shanmin2,3

2022-10-01

10.1021/acs.chemmater.2c02563

CHEMISTRY OF MATERIALS   Impact Factor & Quartile

0897-4756

1520-5002

Cubic tungsten nitrides with high elastic stiffness are promising replacements for metal carbides used in tool applications to achieve enhanced working efficiency. However, due to the difficulties in preparing these nitrides at ambient pressure, their crystal structures and mechanical properties remain largely elusive, which have limited the functionality of these materials. Here, we report a comprehensive study of cubic tungsten nitrides synthesized by a high-pressure method, leading to definitive structural identifications of rocksalt cF8-WN and NbO-type cP6-WN involving atomic deficiencies. Combined with calculations, we find that the structural stabilities of both nitrides are closely related to the atomic deficiency that prevents the filling of unfavorable W: 5d-t2g bands. The disordered N vacancies are decisive for stabilizing cF8-WN, while the ordering of W and N vacancies occurs at 3 GPa and relatively low temperatures and leads to the formation of nearly stoichiometric cP6-WN, rather than previously misassigned cP7-W3N4. Both nitrides exhibit similar excellent mechanical and thermal properties, rivaling and even exceeding WC. Besides, their formation mechanisms are also explored to be associated with atomic vacancies, shedding light on the rational design of functional nitrides by defect chemistry.

SCI

English

Corresponding

National Natural Science Foundation of China["52032001","51671126","12174175"] ; Shenzhen Basic Research Fund[JCYJ20190809173213150] ; Guangdong Innovative amp; Entrepreneurial Research Team Program[2016ZT06C279] ; Shenzhen Peacock Plan[KQTD2016053019134356] ; Shanghai Natural Science Foundation[20ZR1400900]

Chemistry ; Materials Science

Chemistry, Physical ; Materials Science, Multidisciplinary

WOS:000870257500001

AMER CHEMICAL SOC

MATERIALS SCIENCE

Web of Science

1.Harbin Inst Technol, Sch Phys, Harbin 150001, Peoples R China
2.Southern Univ Sci & Technol, Dept Phys, Shenzhen 518055, Peoples R China
3.Southern Univ Sci & Technol, Acad Adv Interdisciplinary Studies, Shenzhen 518055, Peoples R China
4.China Acad Engn Phys, Inst Nucl Phys & Chem, Key Lab Neutron Phys, Mianyang 621999, Peoples R China
5.Chinese Acad Sci, Shanghai Adv Res Inst, Shanghai Synchrotron Radiat Facil, Shanghai 201210, Peoples R China
6.Donghua Univ, Coll Sci, Inst Funct Mat, Shanghai 201620, Peoples R China
7.Donghua Univ, State Key Lab Modificat Chem Fibers & Polymer Mat, Shanghai 201620, Peoples R China

Zhou, Xuefeng,Gu, Chao,Song, Guozhu,et al. Synthesis, Crystal Structures, Mechanical Properties, and Formation Mechanisms of Cubic Nitrides[J]. CHEMISTRY OF MATERIALS,2022.

Zhou, Xuefeng.,Gu, Chao.,Song, Guozhu.,Ma, Dejiang.,Fang, Leiming.,...&Wang, Shanmin.(2022).Synthesis, Crystal Structures, Mechanical Properties, and Formation Mechanisms of Cubic Nitrides.CHEMISTRY OF MATERIALS.

Zhou, Xuefeng,et al."Synthesis, Crystal Structures, Mechanical Properties, and Formation Mechanisms of Cubic Nitrides".CHEMISTRY OF MATERIALS (2022).