Applications of metal-semiconductor phase transition in 2D layered transition metal dichalcogenides Suyeon Cho, Sera Kim, Jinbong Seok, Heejun Yang Motivated by two dimensional graphene, layered transition metal dichalcogenides (TMDs) have attracted scientific interests by their diverse electronic, optical and catalytic properties. In particular, group 6 TMDs such as MoS 2 and MoTe 2 have polymorphs (with metallic octahedral and semiconducting hexagonal phases) which are not present in graphene. Here, we introduce a new concept in 2D materials' studies, structural phase transition, with group 6 TMDs and its current research trend and applications for electric device and electrochemical catalyst. 전이금속칼코젠화합물의반도체연구동향 4
[Fig. 1] 2H phase (left) and 1T phase (right) in TMDs 전이금속칼코겐화합물의다양한구조와물리적인성질 [Fig. 2] High quality single crystals with two different phases (2H and 1T'). 2H and 1T'-MoTe 2 show different atomic arrangements by X-ray diffraction patterns. Large-sized single crystals are shown in the picture with scale bar. 5
[Fig. 3] The schematics for the structural phase transition between semiconducting and metal in MoTe 2. 전이금속칼코겐화합물의구조상전이 레이저조사를이용한동종접합소자 6
[Fig. 4] Phase patterning for ohmic homojuction with semiconducting 2H and metallic 1T' phase in MoTe 2. TEM images show that Te vacancy triggers the structural phase transition. 신재생에너지자원인수소생산을위한물분해전기화학촉매로써의 2 차원물질응용 7
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