Synthesis of Tetrahexahedral Pt Nanocrystals with High Index Faces and High Electro-Oxidation Activity Na Tian,Zhi-You Zhou,Shi-Gang Sun*,Yong Ding and Zhong Lin Wang* Science,May 4,2007 720 0 (210) (210)730) 310 70 200nm Platinum NCs of very unusual tetrahexahedral (THH)shape were prepared at high yield by an electrochemical treatment of Pt nanospheres
(210) (210) (310) (730) (730) A B 1.0 nm (200) (020) 50 nm d=0.20 nm C D 133.6 137.6 Synthesis of Tetrahexahedral Pt Nanocrystals with High Index Faces and High Electro-Oxidation Activity Na Tian, Zhi-You Zhou, Shi-Gang Sun*, Yong Ding and Zhong Lin Wang* Science, May 4, 2007 200 nm B C D [001] E A 200 nm B C D F Platinum NCs of very unusual tetrahexahedral (THH) shape were prepared at high yield by an electrochemical treatment of Pt nanospheres
Synthesis of Tetrahexahedral Pt Nanocrystals with High Index Faces and High Electro-Oxidation Activity Science,May 4,2007 4.0 Pt tetrahexahedra 3 -Pt nanospheres 3.0 Pt tetrahexahedra -PU/C(E-TEK) Pt nanospheres PUC (E-TEK) 3 2.0 2 nm 1.0 HCOOH 0 AE=60mV HCOOH 0 20 40 60 0.0 0.10.20.30.40.5 D --Pt tetrahexahedra 0.8 Pt tetrahexahedra heres 1.2 -Pt nanospheres 4 -PU/C (E-TEK) 0.6 3 0.8 OA 0.2 0.4 0.0 CH,CH2OH 0.0L≤aE0mvCH,cH,oH 20 60 tI .40 0.2-93040.50.6 E/V(SCE) These high-energy surfaces are surprisingly thermal(to 800C)and chemical stable and exhibit much enhanced (up to 400%)catalytic activity for equivalent Pt surface areas for electro-oxidation of small organic fuels such as formic acid and ethanol
Invited Review & Feature Articles Fig. 4 A B C D 0 20 40 60 0.0 1.0 2.0 3.0 4.0 Pt tetrahexahedra Pt nanospheres Pt/C (E-TEK) 0.0 0.1 0.2 0.3 0.4 0.5 0 1 2 3 0 1 2 3 4 Pt tetrahexahedra Pt nanospheres Pt/C (E-TEK) 50 nm HCOOH HCOOH 0 1 2 3 4 0.2 0.3 0.4 0.5 0.6 0.0 0.4 0.8 1.2 R E / V (SCE) Pt tetrahexahedra Pt nanospheres Pt/C (E-TEK) 0 20 40 60 0.0 0.2 0.4 0.6 0.8 1.0 Pt tetrahexahedra Pt nanospheres Pt/C (E-TEK) j / mAcm-2 t / s CH CH3CH 2OH 3CH 2OH E=80 mV E=60 mV Synthesis of Tetrahexahedral Pt Nanocrystals with High Index Faces and High Electro-Oxidation Activity Science, May 4, 2007 These high-energy surfaces are surprisingly thermal (to 800 ºC) and chemical stable and exhibit much enhanced (up to 400%) catalytic activity for equivalent Pt surface areas for electro-oxidation of small organic fuels such as formic acid and ethanol
Model and practical catalysts The single crystal planes vs nanparticles'surface structure Rhombie Dodecahedron 110 Z0N001 310 31) 731 332 Trisoctahedron (31 Tetrahexahedron (751) 62 Hexoctahedro 532i (311) 30 ZONE[011] 111 [o] (100 31 Octahedron Cube Trapezohedron Unit stereographic triangle of Unit stereographic triangle of fcc single-crystal and models polyhedral nanocrystals bounded of surface atomic arrangement by different crystal planes Zhou,Tian,Sun,Faraday Discuss.,2008,140:81-92
Model and practical catalysts The single crystal planes vs nanparticles’ surface structure Unit stereographic triangle of fcc single-crystal and models of surface atomic arrangement Unit stereographic triangle of polyhedral nanocrystals bounded by different crystal planes Zhou, Tian, Sun, Faraday Discuss., 2008,140:81–92
Surface Structure vs.Catalytic Activity N2+3H2→2NH3 B5中心 000 M M 500 (0I0 Fe single a crystal, -:N ---M 100 20atm/700K M M 504 (00) O N2(g) TS 2N(ad) N- Terrace 126-165 Step 218 K.I/mol kJ/mol 30 kl/mol 145 (10) kJ/mol
418 1 25 Surface Structure vs. Catalytic Activity N2 + 3H2 2NH3 Fe single crystal， 20atm/700K N N M M M M M B5 中心 N N
Small Molecules ComrorSurface Structures 10 nn 020200 10011 200mm 20 nm Angew.Chem.Int.Ed.2008,47,8901 J.Am.Chem.Soc.2008,130,17563 Angew.Chem.Int.Ed.2009,48,4808 J.Am.Chem.Soc.2009,131,3152 Angew.Chem.Int.Ed.2009,48,9344 J.Am.Chem.Soc.2009,131,4602 J.Am.Chem.Soc.2009,131,13916
Small Molecules Control Surface Structures 20 n m J. Am. Chem. Soc. 2008, 130, 17563 J. Am. Chem. Soc. 2009, 131, 3152 J. Am. Chem. Soc. 2009, 131, 4602 J. Am. Chem. Soc. 2009, 131, 13916 Angew. Chem. Int. Ed. 2008, 47, 8901 Angew. Chem. Int. Ed. 2009, 48, 4808 Angew. Chem. Int. Ed. 2009, 48, 9344