Janus transition-metal dichalcogenides heterostructures for highly efficient excitonic solar cells

Solar cells based on 2D Janus group-III chalcogenide van der Waals heterostructures

“…In the visible region, the absorption coefficients exceed 10 4 cm −1 , which indicates a high solar energy efficiency. Furthermore, the obtained absorption coefficients are comparable to those previously reported for other 2D materials, such as Janus TMDs, 97 PtSSe, 43 and γ-BTe. 105 This indicates that the investigated monolayers are suitable for use in optoelectronic devices.…”

“…Moreover, the amount of charge acquired by the S atoms is larger than that received by the other chalcogenide atoms since the charge transfer relies on the difference in electronegativity between the metal and the chalcogenide atoms, which decreases as moving down in the chalcogen group (i.e., S → Se → Te). 97 Also, increasing (decreasing) the Bader charge transfer between the metal and chalcogenide atoms strengthens (weakens) the covalent bonds, resulting in a decrease (increase) in the bond length. The induced mirror symmetry breaking in Janus structures leads to the creation of intrinsic electric dipoles pointing from the Y atom to the X atom in the Janus M 2 XY and MM′XY monolayers, and from the M atom to the M′ atom in the Janus MM′ X 2 monolayers, as shown in Fig.…”

“…, S → Se → Te). 97 Also, increasing (decreasing) the Bader charge transfer between the metal and chalcogenide atoms strengthens (weakens) the covalent bonds, resulting in a decrease (increase) in the bond length. The induced mirror symmetry breaking in Janus structures leads to the creation of intrinsic electric dipoles pointing from the Y atom to the X atom in the Janus M 2 XY and MM′XY monolayers, and from the M atom to the M′ atom in the Janus MM′X 2 monolayers, as shown in Fig.…”

Theoretical design of two-dimensional AMInP2X3Y3 (AM = Li, Na, K; X/Y = S, Se, Te) monolayers for highly efficient excitonic solar cells

“…Furthermore, four of these have PCEs higher than 20%. The PCEs of the NT/InSe, KT/ MoGe 2 N 4 , NTS/MoGe 2 N 4 , and KTS/T-HfSe 2 XSCs are calculated as 22.12%, 18.23%, 21.93%, and 18.00%, respectively, all of which are higher than the best-certified efficiencies of organic solar cells (13%), 12,13 ternary polymer solar cells (PM6:PDHP-Th: Y6 ternary PSCs, 16.8%), 66 and dye-sensitized solar cells (12%), 21 and competitive with the theoretical values of most other 2D heterostructures (e.g., g-SiC 2 based systems (12-20%), 67 ZrS 3 /HfS 3 (16-18%), 25 MoS 2 /phosphorene (17.5%), 24,68 GeSe/SnS (18%), 69 In 2 STe/Al 2 SSe (21.41%), 9 boron pnictide/MoSSe (22.97%), 28 Janus TMDs based XSCs (15-23%) 14,70 and of perovskite solar cells (22.1%) 71 ). Moreover, we also calculated the PCE for these heterojunction solar cells by excluding the SOC effect for comparison as presented in Table S3 (ESI †).…”

Janus β-Te2X (X = S, Se) monolayers for efficient excitonic solar cells and photocatalytic water splitting

“…This results in boosting the STH efficiency of photocatalysts such as MoSSe, 41 B 2 P 6 , 42 WSSe, 43 WSeTe, 44 Pd 4 X 3 Y 3 (X, Y = S, Se, and Te; X ≠ Y), 45 etc. Also, PCEs of heterojunction solar cells based on Janus transition metal dichalcogenides (TMDs), 46 In 2 SeTe, 47 α-Te 2 S, 48 etc. , are also found to be enhanced.…”