Supplementry Informtion for the Journl of Americn Chemicl Society The Americn Chemicl Society 04 Enhnced Photoctlytic CO -Reduction Activity of Antse TiO y Coexposed {00} nd {0} Fcets Jiguo Yu,*, Jingxing Low, Wei Xio, Peng Zhou, Mietek Jroniec*, Stte Key Lortory of Advnced Technology for Mteril Synthesis nd Processing, Wuhn University of Technology, Luoshi Rod #, Wuhn 430070, P. R. Chin. Deprtment of Chemistry nd Biochemistry, Kent Stte UniVersity, Kent, Ohio 444, USA. Emil: jiguoyu@yhoo.com; jroniec@kent.edu Experimentl Section Computtionl detils. The DOS plots of ntse TiO were otined y using the firstprinciples DFT clcultions to specify the electronic structure of {00} nd {0} fcets in this photoctlyst. CASTEP pckge sed on the plne-wve-pseudo potentil pproch ws used to perform DFT clcultions. Smple preprtion. TiO smples were synthesized y using solvotherml method. In this synthesis 5 ml of tetrutyl titnte were mixed with 0, 3, 4.5, 6 nd 9 ml of HF solution (with concentrtion 40 wt%), respectively, under stirring for 30 min. Then, the solution ws trnsferred into 00 ml Teflon-lined utoclve nd kept t 80 C for 4 h. After solvotherml rection, the resulting white precipittes were collected nd wshed with ethnol nd distilled wter for three times. Then, the smples were dried in n oven t 80 C for 6 h. The prepred smples were denoted s HF0, HF3, HF4.5, HF6, nd HF9, respectively, ccording to the mount of hydrofluoric cid solution dded. To remove the surfce fluorine ions from the prepred smples, ll the s-prepred smples were heted t 550 C for h in furnce. Then, the smples were cooled to room temperture. Photoctlytic experiments. The photoctlytic reduction of CO ws crried out in 00 ml home-mde Pyrex rector t mient temperture nd tmospheric pressure. A 300 W simulted solr Xe rc lmp ws used s the light source nd positioned 0 cm ove the photoctlytic rector. In typicl photoctlytic reduction experiment, 00 mg of the smple ws put into the glss rector nd dded to 0 ml of deionized wter. The ctlyst ws ultrsoniclly dispersed for 30 min, then, dried t 80 o C for h to evporte wter. The smple deposited on the ottom of the rector ws in the form of thin film. Before the irrdition, the rector ws seled nd lown with nitrogen for 30 min to remove ir nd ensure tht the rection system ws under neroic conditions. CO nd H O vpour were in-situ generted y the rection of NHCO 3 (0. g; introduced into the rector efore seling) nd HCl queous S
Supplementry Informtion for the Journl of Americn Chemicl Society The Americn Chemicl Society 04 solution (0.5 ml, 4M), which ws introduced into the rector y syringe. ml of mixed gs ws tken out from the rector t given intervls ( h) during the irrdition nd nlyzed y using gs chromtogrph (GC-04C, Shimdzu, Jpn) equipped with flme ionized detector (FID) nd methnizer. Products were nlyzed on the sis of retention time dt for the nlyte nd the stndrd gseous smple. The crrier gs used in the GC-04C ws high purity nitrogen. The rection product ws lso nlyzed y nother gs chromtogrph (GC-4C, Shimdzu, Jpn, TCD, 5 Å moleculr sieve column) with nitrogen used s crrier gs. Blnk experiments were crried out in the sence of CO or light irrdition to confirm tht CO nd light were two key fctors influencing the photoctlytic CO reduction. Smple chrcteriztion. Morphologicl oservtions were crried out on n S-4800 field emission scnning electron microscope (SEM, Hitchi, Jpn) nd connected with n Oxford Instruments X-ry nlysis system. TEM nlyses were performed with JEM-00 electron microscope (JEOL, Jpn), using 00 kv ccelerting voltge. The XRD ws conducted on n X-ry diffrctometer (type HZG4B-PC) using Cu K rdition t scn rte of 0.05 s. The ccelerting voltge nd pplied current were 40 kv nd 80 ma, respectively. The S BET specific surfce re of the powders ws determined y using nitrogen dsorption dt recorded on Micromeritics ASAP 00 nitrogen dsorption pprtus (USA). All the smples were degssed t 80 C prior to nitrogen dsorption mesurements. The BET surfce re ws otined y multipoint BET method using the dsorption dt in the reltive pressure (P/P 0 ) rnge of 0.05 0.3. The desorption rnch of the isotherm ws used to otin the pore size distriution vi the Brret Joyner Hlender (BJH) method derived for cylindricl pores. The volume dsored t the reltive pressure (P/P 0 ) of 0.994 ws used to determine the pore volume nd the verge pore size. The X-ry photoelectron spectroscopy (XPS) mesurement ws otined in n ultrhigh vcuum VGESCALAB 0 electron spectrometer equipped with multichnnel detector, using Mg K (53.6 ev) rdition (operted t 00 W) of twin node in the constnt nlyzer energy mode with pss energy of 30 ev. All the inding energies were referenced to the C s pek t 84.8 ev of the surfce dventitious cron. Electrochemicl test. EIS ws tested t the open circuit potentil. Electrochemicl nlyzer (CHI660C instruments, CHI, Chin) in stndrd three-electrode system ws used to perform the electrochemicl mesurement. The photoctlyst smple ws coted onto cm.5 cm fluorine-tin oxide (FTO) glss electrode, nd then nneled t 400 o C for h. N SO 4 queous solution ( M) ws used s the electrolyte in this system. The smple coted FTO, Pt wire nd Ag/AgCl were used s the working electrode, counter electrode, nd reference electrode in the electrochemicl nlyzer system, respectively. A low power UV-LEDs (3 W, 365 nm) ws used s light source. S
Supplementry Informtion for the Journl of Americn Chemicl Society The Americn Chemicl Society 04 Figure S. () The thermodynmiclly stle ntse TiO under equilirium conditions nd () the growth of ntse TiO long [00] nd [0] directions ccording to the Wulff construction. Figure S. Schemtic of tomic surfce structure of ntse TiO () {0} nd () {00} fcets. S3
Supplementry Informtion for the Journl of Americn Chemicl Society The Americn Chemicl Society 04 E (A) (B) 00 0 G F θ I H Figure S3. A) Sl model of ntse TiO single crystl. B) Equilirium model of ntse TiO single crystl. C) Percentge of {00} fcets cn e clculted s follows [-4]: S00 S 8( EG EF 0 % S00 S00 S S 8( 00 0 EG ) EF ) 4( ) cos cos cos cos cos cos S4
Supplementry Informtion for the Journl of Americn Chemicl Society The Americn Chemicl Society 04 cos cos ( ) Here θ is the theoreticl vlue (68.3 o ) for the ngle etween the [00] nd [0] fcets of ntse. As indicted in the sl model, two independent prmeters nd denote lengths of the side of the ipyrmid nd the side of the squre {00} trunction fcets, respectively. References [] Xing, Q. J.; Yu, J. G.; Jroniec, M. Chem. Commun., 0, 47, 453. [] Yng, H. G.; Sun, C. H.; Qio, S. Z.; Zou, J.; Liu, G.; Smith, S. C.; Cheng, H. M.; Lu, G. Q. Nture, 008, 453, 638. [3] Zhng, D. Q.; Li, G. S.; Yng, X. F.; Yu, J. C. Chem. Commun., 009, 438. [4] Yu, J. G.; Di, G. P.; Xing, Q. J.; Jroniec, M. J. Mter. Chem., 0,, 049. Reltive intesity (.u.) HF9 HF6 HF4.5 HF3 HF0 (0) (004) (00) (05) () (04) 0 0 30 40 50 60 70 Thet (degree) Figure S4. XRD ptterns of the TiO smples prepred y vrying the HF mount. S5
Supplementry Informtion for the Journl of Americn Chemicl Society The Americn Chemicl Society 04 Reltive intensity (.u.) Ti 3p Ti 3s C s Ti p O s Ti s O KLL HF 4.5 HF 0 0 00 400 600 800 Binding energy (ev) Figure S5. XPS survey spectr of HF0 nd HF4.5. Asornce (.u.) HF0 HF4.5 HF9 0 350 400 450 500 550 600 Wvelength (nm) Figure S6. UV-Vis sorption spectr of HF0, HF4.5 nd HF9. S6
Supplementry Informtion for the Journl of Americn Chemicl Society The Americn Chemicl Society 04 Volume dsored (cm 3 /g,stp) 300 50 00 50 00 50 0 00 Pore dimeter (nm) HF0 HF4.5 0 0.0 0. 0.4 0.6 0.8.0 Reltive pressure (P/P0) Figure S7. Nitrogen dsorption-desorption isotherms nd the corresponding pore size distriution curves (inset) of HF0 nd HF4.5. Figure S8. EIS spectr of the TiO smples prepred y vrying the HF mount. S7
Supplementry Informtion for the Journl of Americn Chemicl Society The Americn Chemicl Society 04 Tle S. Comprison of the specific surfce res, ctivity nd specific ctivity of the HF0, HF4.5 nd HF9 smples. Smple BET (m /g) PV (cm 3 /g) APS (nm) Activity molh - g - ) Specific ctivity molh - m - ) HF0 07 0.3.9 0.5.4 x 0-3 HF4.5 45 0. 5..35 30 x 0-3 HF9 30 0. 6.8 0.55 8.3 x 0-3 PV: Pore volume; APS: Averge pore size S8