Programme

P.4 -- Poster, VCTP-47

Date: Tuesday, 2 August 2022

Time: 08:30 - 10:00

Structural diversity and optoelectronic properties of chemical modification pentagonal quantum dots

Pham Thi Bich Thao (1), Nguyen Thi My Hang(1), Truong Vo Minh Nguyet (1), Nguyen Hai Dang (2), Pham Vu Nhat (3), and Nguyen Thanh Tien (1)

(1) Department of Physics, College of Natural Sciences, Can Tho University (2) College of College of Basic Sciences, Nam Can Tho University (3) Department of Chemistry, College of Natural Sciences, Can Tho University

A first-principle study of the structural diversity and optoelectronic properties of the small penta-graphene (PG) quantum dots (PGQDs) has been performed. The stability and optoelectronic properties of the PGQDs are investigated under the effect of chemical modifications. PGQDs are edge functionalized by non-metallic atoms (H, P, Si, O) such as identical edge termination (H-PGQD, P-PGQD, Si-PGQD, O-PGQD) and alternate edge termination (H-O-PGQD, Si-O-PGQD, H-P-PGQD). Further, H-PGQDs are also doped and co-doped with B and P atoms. All studied structures are stable with strong electronic quantization and exhibit semiconducting or metal properties depending on the termination and doping elements and their site. Absorption peaks in the visible region were not observed for hydrogen passivation PGQDs. However, some absorption peaks appear in this region for edge-passivated. In addition, there are changes in the electronic properties of PGQD samples containing impurities B, P, or BP also give a shift in the peak of the spectrum to the visible region from the ultraviolet region of the corresponding pure sample. This is because of various hybridization effects in PG and PGQDs with edge passivation and atom doping. The enhanced reactivity, and controllable electronic properties of edge passivation, and doping make PGQDs ideal for new nanodevice applications.

Presenter: Nguyen Thi My Hang