Computational Mater ials Design and Disc over y E ner gy and E - PowerPoint PPT Presentation

Computational Mater ials Design and Disc over y E ner gy and E lec tr onic Applic ations Synthesis Str uc tur e Pr oper ties Rechargeable batteries Supercapacitors Super- computer Fuel cell catalysts Photocatalysts First principles-based computations can provide invaluable guidance on the rational design and synthesis of new materials with desired properties, without slow and costly try-and-modify test and manufacturing cycles!

Materials Challenges New Materials ..! New Materials ..! H 2  Cheap  Abundant  Efficient  Safe

Hwang Research Group Computational Design of Nanomaterials for Energy and Electronic Applications Our research has a well ‐ balanced emphasis on applications fundamentals  strategies for predictive multiscale, multiphysics computational models by integrating various state ‐ of ‐ the ‐ art theoretical methods at different length and time scales.  a quantitative understanding of the relationship between the synthesis, structure, and properties of nanostructured materials and systems.

Lithium Ion Batteries Recent achievements  E luc ida te the lithia tio n me c ha nisms o f silic o n-b a se d na no ma te ria ls.  Pro vide ma ny insig hts into ho w to de sig n na no struc ture s a nd c o mpo site s to a c hie ve de sire d pro pe rtie s a nd pe rfo rma nc e . Si-rich suboxides Surface/Interface Impacts … highlights the possibility of designing  Fast Li diffusion (fast charge rate) high performance Si suboxide anodes  Facile atomic rearrangement & Uniform via fine-tuning of the lithiation/delithiation (improved cyclability) oxidation conditions Recent Publications 1. Appl. Surf. Sc i. 323, 78 (2014)-invite d 2. J. Po we r So urc e s 263 C, 252 (2014) 3. Che m. Ma te r. 25, 3435 (2013) 4. J. Phys. Che m. C 117, 9598 (2013) 5. Surf. Sc i. 612, 16 (2013) 6. J. Phys. Che m. C 115, 20018 (2011) First Principles-based 7. J. Phys. Che m. C 115, 2514 (2011) Molecular Modeling 8. J. Phys. Che m. C 114, 17942 (2010)

Graphene-based Supercapacitors Recent achievements Structural deformation effect  I de ntify the ke y fa c to rs de te rmining the inte rfa c ia l c a pa c ita nc e o f g ra phe ne -b a se d supe rc a pa c ito rs  Pro vide ne w insig ht into the impa c ts o f the c he mic a l a nd/ o r me c ha nic a l mo dific a tio ns o f g ra phe ne -like c a rb o n e le c tro de s o n the supe rc a pa c ito r pe rfo rma nc e . Doping effect Recent Publications 1. J. Che m. Phys., a c c e pte d (2014) 2. J. Phys. Che m. C 118, 21770 (2014) 3. ACS Appl. Ma te r. I nte rfa c e s 6, 12168 4. Ca rb o n 68, 734 (2014) 5. J. Phys. Che m. C 117, 23539 (2013) TOC First Principles Modeling 6. Phys. Che m. Che m. Phys. 15, 19741 7. J. Phys. Che m. C 117, 5610 (2013) 8. J. E le c tro c he m. So c . 160, A1 (2013)

Solar-powered H 2 Production Recent achievements  E luc ida te the e ffe c ts o f c he mic a l do ping a nd struc tura l disto rtio ns o n c ha rg e c a rrie r lo c a liza tio n a nd tra nspo rt, a nd the ir impa c ts o n the pho to c a ta lytic pe rfo rma nc e .  I de ntify the ro le o f pho to g e ne ra te d c ha rg e c a rrie rs in pro mo ting surfa c e re a c tio ns. Photocatalytic reaction Doping/Structural distortion Computational Sc r eening, Design & E valuation … highlights that excess electrons and holes can  Band gaps and band alignments synergetically contribute to CO photooxidation on  Charge localization and transport TiO 2 (110) under UV irradiation. Candidate Photocatalysts  Defect formation and properties Recent Publications Electron doping effect  Visib le lig ht a b so rptio n 1. ACS Ca ta l. 4, 4051 (2014) (Ba nd g a p = 1.6-2.2 e V) 2. Phys. Che m. Che m. Phys. 17, 256 (2015)  Co rre c t b a nd e dg e po sitio ns 3. Appl. Phys. L e tt. 103, 131603 (2013)  Hig h c ha rg e c a rrie r mo b ility 4. Phys. Re v. B 87, 205202 (2013)  L o w de fe c t de nsity 5. Phys. Re v. B 86, 165209 (2012)  Hig h surfa c e re a c tivity 6. J. Phys. Che m. C 115, 17870 (2011)  Hig h re sista nc e to pho to c o rrsio n 7. Mo re c o ming so o n …

Electrocatalysis in Fuel Cells De ve lo p lo w-Pt o r Pt-fre e me ta l c a ta lysts tha t a re mo re a c tive , mo re a b unda nt, a nd le ss e xpe nsive tha n the c urre ntly use d Pt-b a se d c a ta lysts. First principles-based Precise determination of the atomic surface ensembles arrangements in near ‐ surface layers Recent Publications Quantum Mechanics ORR activity of selected multimetallic 1. J. Che m. Phys. 139, 201104 (2013) nanocatalysts; ensemble, ligand, size ‐ shape effects ..??? 2. Che m. So c . Re v. 42, 5002 (2013) 3. J. Am. Che m. So c . 135, 436 (2013) model NP Shapes 4. Phys. Che m. Che m. Phys. 15, 12118 5. J. Che m. Phys. 139, 164703 (2013) Classical Force Field 6. Che m. Ma te r. 25, 530 (2013) Fast exploration of the coarse space 7. J. Phys. Che m. L e tt. 3, 566 (2012) of nanoparticle shapes 8. J. Phys. Che m. C 115, 21205 (2012) 9. Ca ta lysis T o da y 165, 138 (2011) 10.J. Phys. Che m. C 114, 21516 (2010) 11.J. Phys. Che m. C 114, 14922 (2010) 12.J. Phys. Che m. C 113, 12943 (2009) Multisc ale Modeling Str ategy for sc r eening multimetallic elec tr oc atalysts

Waste Heat Conversion into Electricity Unde rsta nd the pro pe rtie s a nd pe rfo rma nc e o f na no ma te ria ls fo r the rmo e le c tric a pplic a tio ns with a pa rtic ula r fo c us o n the ir the rma l c o nduc tivity Thermal Conductivity Control via Alloying Chemic al Doping Defec t engineer ing Nanostr uc tur ing Compositing Recent Publications 1. J. Appl. Phys. 114, 174910 (2013) 2. Phys. Re v. B 86, 165209 (2012) 3. Na no L e tt. 12, 2918 (2012) 4. Phys. Re v. B 85, 125204 (2012) 5. Phys. Re v. B 83, 125202 (2011) 6. Mo re c o ming so o n

CO 2 Capture and Conversion …. pro vide the g uiding princ iple s fo r the ra tio na l de sig n a nd synthe sis o f no ve l re g e ne ra b le a mine -b a se d so lve nts to re a lize the de sire d pro pe rtie s a nd pe rfo rma nc e fo r CO 2 c a pture , thro ug h syste ma tic the o re tic a l inve stig a tio ns o f the a to mistic me c ha nisms g o ve rning CO 2 c a pture a nd so lve nt re g e ne ra tio n.

Top-notch Computational Resources High Performance Computing Systems at UT-Austin (http://www.tacc.utexas.edu) (1) “STAMPEDE” One of the largest computing systems in the world for open science research. 102,400 Processing Cores  205 TB Memory  7+ Petaflops of Peak Performance  (2) “LONESTAR” One of the most powerful academic supercomputers in the world. 22,656 Processing Cores  44 TB Memory  300+ Teraflops of Peak Performance  Suc c e ssful c o mple tio n o f o ur e xte nsive first princ iple s-b a se d inve stig a tio ns c a n b e fa c ilita te d b y utilizing the wo rld’ s to p-c la ss supe rc o mputing fa c ilitie s.