2D heterostructure and data mining for thin films.pptx

2D materials and heterostructure

1. SHEN LEI National University of Singapore High-Throughput Computational Screening and Data Mining of 2D Heterostructures for Thin-Film Solar Cell Applications

2. Project investigators Project collaborators Yuan Ping Feng (PI) Miguel Dias Costa (Co-PI) Shen Lei (Co-PI) Kristin Persson Shyue Ping Ong “ Towards a Genome for Advanced Two-dimensional Materials ” Ministry of Education Singapore

3. http://globalmaterialsnetwork.org A Node of 2D materials database (Coming Soon…)

4. Part I Part II Future plan & conclusions 1 Part I Introduction of 2D materials-based excitonic solar cells A simple case of phosphorene -TMD heterojunctions 2 Part II Introduction of materials genome project High-throughput screening of 2D materials Band structure and band offset High power conversion efficiency (PCE) heterostructures 3 Future plan and conclusions Build a NODE of 2D materials database in Singapore Seek academic and industry collaborations Outline

5. Part I Part II Future plan & conclusions 2D excitonic solar cells: A case of phosphorene -TMDs heterojunctions Part I Ganesan , et. al., APL 108 , 122105 (2016)

6. Part I Part II Future plan & conclusions Introduction of 2D materials A. K. Geim , Nature , 499 , 414 (2013)

7. Part I Part II Future plan & conclusions Introduction of 2D materials White Red Black Symmetry bcc triclinic Orthorhombic Ban d gap (eV) 2.1 2.0 0.34 Melting point (ºC) 44 400 610 Allotropic Phosphorus Direct band gap ( Eg =1.88 eV ); High carrier mobility

8. Part I Part II Future plan & conclusions Introduction of 2D excitonic solar cell Mechanism of excitonic solar cell Flexible Light Cheap light

9. Part I Part II Future plan & conclusions Introduction of 2D excitonic solar cell Mechanism of excitonic solar cell light Flexible Light Cheap

10. Part I Part II Future plan & conclusions Introduction of 2D excitonic solar cell Mechanism of excitonic solar cell light Flexible Light Cheap

11. Part I Part II Future plan & conclusions Power conversion efficiency (PCE) light η : Power conversion efficiency J sc : Short circuit current V oc : Open circuit voltage β FF : Fill factor P( ħ ω ) : Solar spectrum E opt : Optical gap ΔE c : Conduction band offset Bernardi , ACS Nano 6 , 10082 (2012)

12. Part I Part II Future plan & conclusions Band alignment Donors Acceptors

13. Part I Part II Future plan & conclusions Calculated PCE Donor optical gap ( eV ) Conduction band offset ( eV ) 1 1.5 2 2.5 3 3.5 0.2 0.4 0.6 0.8 1.0 1.2 20% 18% 16% 14% 12% 10% 8% 6%

14. Donor optical gap ( eV ) Conduction band offset ( eV ) 1 1.5 2 2.5 3 3.5 0.2 0.4 0.6 0.8 1.0 1.2 20% 18% 16% 14% 12% 10% 8% 6% Strained phosphorene MoS 2 MoTe 2 MoSe 2 WS 2 WSe 2 WTe 2 TiS 2 ZrS 2 Part I Part II Future plan & conclusions Calculated PCE

15. Part I Part II Future plan & conclusions High-throughput computational screening of 2D materials and data mining of heterostructures for excitonic solar cells with high PCE Part II Linghu, et. al., ( unpublished )

16. 2X faster & 2X cheaper ! Materials Genome Initiative Part I Part II Future plan & conclusions Introduction of MGI

17. Part I Part II Future plan & conclusions Introduction of MGI

18. Part I Part II Future plan & conclusions High-throughput screening 2D materials inorganic crystal structure database (>100,000) 2D materials (~200) Non-metallic 2D materials ( n ~42) n n m= (n 2 -n)/2 n Heterostructures of 2D materials ( m ~900) PCE > 17% (~58)

19. Part I Part II Future plan & conclusions Screened non-metallic 2D materials Graphene -like and Derivatives Graphane Silicane Germanane Phospherene Transition Metal Mono chalcogenides InS GaTe CdS InSe GaSe ZnS InTe Transition Metal Di chalcogenides TiS 2 ZrS 2 HfS 2 MoS 2 WS 2 NiS 2 PdS 2 PtS 2 SnS 2 HfSe 2 MoSe 2 WSe 2 NiSe 2 PdSe 2 PtSe 2 SnSe 2 MoTe 2 WTe 2 NiO 2 PdTe 2 PtTe 2 MoO 2 WO 2 SnO 2 Others BN BP BAs BSb SiC Tri chalcogenides Bi 2 Se 3 Bi 2 Te 3

20. Band Gap (eV) 1: NiSe 2 2 : BSb 3 : PdTe 2 4 : TiS 2 5 : NiS 2 6 : ZrSe 2 7 : PdSe 2 8 : PtTe 2 10: HfSe 2 11: BP 12: Bi 2 Te 3 14: WTe 2 15: MoO 2 16: MoTe 2 18: PdS 2 19: Germanane 20: ZrS 2 21: PtSe 2 22: MoSe 2 23: WO 2 25: InTe 26: GaTe 27: MoS 2 28: HfS 2 29: InSe 30: WS 2 32: InS 33: PtS 2 34: CdS 35: GaSe 36: NiO 2 17: Phosphorene 9 : BAs 24: WSe 2 42: BN 37: Silicane 38: SiC 39: ZnS 40: SnO 2 41: Graphane 13: Bi 2 S e 3 31: SnS 2 Part I Part II Future plan & conclusions Screened non-metallic 2D materials Band gap of 42 semiconducting 2D materials

21. BAs-BP ZrSe 2 -PdS 2 ZrSe 2 -Bi 2 Se 3 ZrSe 2 -WO 2 ZrSe 2 -ZrS 2 PdSe 2 -HfS 2 PtTe 2 -BAs HfSe 2 -PdSe 2 Bi 2 Se 3 -WO 2 WTe 2 -Germanane Bi 2 Se 3 -ZrS 2 HfSe 2 -PdSe 2 Phosphorene-PtTe 2 MoTe 2 -WS 2 Bi 2 Se 3 -NiS 2 WTe 2 -CdS WTe 2 -GaSe WTe 2 -GaTe BP- BSb BP-MoS 2 HfSe 2 -NiSe 2 Part I Part II Future plan & conclusions Data mining of high-PCE heterostructures 21 over 58 have PCE over 20%

22. Part I Part II Future plan & conclusions Data mining of high-PCE heterostructures PCE (%) Donor Acceptor 23.5 HfSe 2 PdSe 2 23.3 Bi 2 Se 3 WO2 23.1 BAs BP 22.4 ZrSe 2 PdS 2 22.4 Bi 2 Se 3 ZrS 2 22.4 WTe 2 Germanane 22.1 ZrSe 2 Bi 2 Se 3 21.6 ZrSe 2 WO 2 21.3 Bi 2 Se 3 NiS 2 21.2 HfSe 2 HfS 2 21.2 BP BSb 21.0 WTe 2 CdS 20.7 ZrSe 2 ZrS 2 20.6 PdSe 2 HfS 2 PCE (%) Donor Acceptor 20.6 Phosphorene PtTe 2 20.6 WTe 2 GaSe 20.5 PtTe 2 BAs 20.5 HfSe 2 NiSe 2 20.3 BP MoS 2 20.2 WTe 2 GaTe 20.1 MoTe 2 WS 2 20.1 BAs BSb 19.9 PtTe 2 BP 19.8 PdSe 2 NiSe 2 19.7 PdS 2 Bi 2 Se 3 19.6 WTe 2 MoTe 2 19.6 MoTe 2 MoSe 2 PCE (%) Donor Acceptor 19.6 MoTe 2 InTe 19.4 PdS 2 WO 2 19.0 ZrSe 2 NiS 2 19.0 BAs MoS 2 18.9 BP PtSe 2 18.9 PdS 2 ZrS 2 18.8 Phosphorene BAs 18.7 Germanane CdS 18.6 HfSe 2 SnS 2 18.6 MoTe 2 Phosphorene 18.6 Phosphorene BP 18.5 BP InSe 18.4 HfSe 2 ZrSe 2 18.3 Germanane GaSe 18.2 PdS 2 NiS 2 PCE (%) Donor Acceptor 18.1 PtSe 2 InSe 18.1 Germanane GaTe 17.9 ZrS 2 NiS 2 17.9 MoSe 2 InTe 17.7 HfSe 2 PdS 2 17.7 Germanane MoTe 2 17.5 HfSe 2 Bi 2 Se 3 17.5 PdSe 2 SnS 2 17.3 MoSe 2 Phosphorene 17.3 MoTe2 PtTe2 17.3 PtSe2 PdTe2 17.3 PtSe2 InS 17.2 BP PdTe2 17.0 HfSe2 WO2 17.0 WTe2 WS2 17.0 BAs PtSe2

23. Spin-Orbit Coupling Wave vector Energy Spin-orbit splitting Conduction band minimum Valence band maximum MoS 2 3 148 WS 2 26 430 MoSe 2 7 184 WSe 2 38 466 MoTe 2 34 219 Conduction band splitting ( meV ) Valence band splitting ( meV ) m l =0 m l =±2 Part I Part II Future plan & conclusions Discussion

24. Part I Part II Future plan & conclusions Mine data for other applications Setup Node of a 2D materials database Seek collaborations** (academic and industry) …… Future plan **we will engage theorists to develop theories and computational methods catered for 2D materials, work with experimentalists to synthesize and characterize the materials, and partner industries to test and deploy the new 2D materials.

25. Photocatalyst for photo-splitting water Step 1 : Photon with energy above 1.23eV ( λ <~1000 nm) is absorbed. Step 2 : Photoexcited electrons and holes separate and migrate to surface. Step 3 : Adsorbed water is reduced and oxidized by the electrons and holes, and thus H 2 product. Domen et al. J . Phys. Chem. 2007 H 2 O→2H 2 +O 2 ∆ V=1.23V Part I Part II Future plan & conclusions Future plan 1

26. Band requirements for photocatalyst Band gap > 1.23eV Sufficiently small to make efficient use of solar spectrum (~2eV) Band edges must be matched with the redox potentials of water -4.44 eV -5.67 eV Part I Part II Future plan & conclusions Future plan 1

27. Metal contacts to 2D semiconductors Part I Part II Future plan & conclusions PHYS. REV. X 4 , 031005 (2014) Substrate Future plan 2

28. Conclusions Did some preliminary works on materials genome project Collaborated with Materials Project (U.S.) Seeking more 2D materials Doing material property calculations Will build database Node Will seek industry collaborations Today Past Future Part I Part II Future plan & conclusions Acknowledgement : Thanks Linghu J., Vellay G., Cai P.

29. THANK YOU

30. High-throughput computing environment

31. Database

32. Analysis