Structure-engineering the stability, electronic, optical and photocatalytic properties of hexagonal C₂P₂monolayers

Abstract

Structure engineering has presented unique charm in material science field including material design and modification. Herein, we have applied structure engineering to double-sublayer hexagonal C2P2 monolayers so as to form...

Novel C4P2 monolayers: forming Z-scheme heterojunction and Janus structure for high-efficiency metal-free photocatalytic water splitting

“…These values are lower than those of C 2 P 2 monolayers reported in our previous work. 24 The relatively low E coh values suggest that both α-C 4 P 2 and β-C 4 P 2 monolayers exhibit stable energetics. Subsequent to our cohesive energy calculations, we probed the phonon spectra of α-C 4 P 2 and β-C 4 P 2 , as delineated in Fig.…”

“…This structure presents a pronounced indirect band gap, underscoring its potential efficacy in visible-light-mediated photocatalytic water splitting processes. 24 Nevertheless, despite the evident potential of these two C 2 P 2 monolayer variants in photocatalytic water splitting, they possess a notable limitation. In comparison to three-dimensional materials, two-dimensional materials typically exhibit higher carrier mobility, and their low-energy optical absorption is predominantly attributed to in-plane absorption, thereby facilitating the rapid in-plane migration of photo-generated electrons and holes.…”

Metal-free Janus α- and β-SiCP4: designing stable and efficient two-dimensional semiconductors for water splitting

“…The optical absorption spectra of α- and β-SiCP 4 (shown in Fig. 6) were calculated by using the following formulas: 63 A ( ω ) = 1 − e − α ( ω )·Δ z where A ( ω ) presents the optical absorbance, α ( ω ) presents the absorption coefficient, Δ Z presents the primitive-cell size in the direction of a vacuum layer, n presents the index of refraction, ε 1 and ε 2 respectively present the real and imaginary parts of their dielectric function, ω presents the incident light frequency, and c presents the speed of light in the vacuum. Due to optical absorption is reduced when polarization is perpendicular to the plane, we mainly concentrate on absorption spectra with polarization parallel to the plane of the monolayer α- and β-SiCP 4 , as shown in Fig.…”