Journal of Advances in Nanomaterials

Download PDF (549.6 KB) PP. 127 - 132 Pub. Date: April 19, 2017

DOI: 10.22606/jan.2017.22006

• Surya Kumar Vatti
  National Centre for Catalysis Research (NCCR) Indian Institute of Technology Madras, Chennai-600036, India
• Krishnamurthy Konda Ramaswamy
  
  National Centre for Catalysis Research (NCCR) Indian Institute of Technology Madras, Chennai-600036, India
• Viswanathan Balasubramanaian^*
  
  National Centre for Catalysis Research (NCCR) Indian Institute of Technology Madras, Chennai-600036, India

Palladium nano particles in tetrahedral (Td), octahedral (Oh) and spherical (Sp) shapes, supported on hydrotalcite, were synthesized and characterized by XRD and TEM. Td shaped Pd nano particles, with maximum number of exposed (111) planes of Pd, display maximum turn over frequency (TOF) / intrinsic activity for hydrogenation of cinnamaldehyde, indicating the importance of active site geometry. Oh & Sp shaped Pd nano particles that expose both (111) and (100) planes have relatively lower intrinsic activity. For a given reaction, it is essential that appropriate active site geometry, as dictated by the shape/morphology of nano particles be made available. Synthesis and stabilization of such shape controlled nano particles is of prime importance in developing catalysts with higher activity.

Pd nano particles, shape control, active site geometry, cinnamaldehyde, hydrogenation, TOF.

[1] J. A. Anderson and M. Fernández Garcia, “Supported metals in Catalysis” Imperial College Press, London, 2005.

[2] P. Gallezot and D. Richard, “Selective Hydrogenation of unsaturated Aldehydes” Catal. Rev.-Sci. Eng., vol. 40, no.1, pp.81-126, 1998; B. Coq and F. Figueras, “Structure-activity relationships in metals- Some aspects of particle size, bimetallic and support effects” Co-ord. Chem. Rev., vol.178–180, no.2, pp.1753–1783, 1998.

[3] D .Uzio and G. Berhault “Factors governing reactivity of metallic nano particles” Catal.Rev-Sci.Eng., vol.52, no.1, pp106-121, 2010.

[4] M. G. Prakash, R. Mahalakshmy, K. R. Krishnamurthy and B. Viswanathan, “Selective hydrogenation of cinnamaldehyde on nickel nano particles supported on titania-Role of catalyst preparation methods” Catal.: Sci. Technol. vol .5, no.6, pp.3313-3321, 2015.

[5] N. Semagina and L. Kiwi-Minsker “Palladium Nano hexagons and Nano spheres in selective alkyne Dehydrogenation” Catal. Lett. vol.127, No.3-4, pp.334-338, 2009.

[6] H. Zhang, M. Jin, Y. Xiong, B. Lim, and Y. Xia,“Shape-Controlled Synthesis of Pd nano crystals and their catalytic applications”’ Acc. Chem. Res. vol. 46, no. 8, pp.1783-1794, 2013.

[7] R. Wang, H. He, J. Wang, L. Liu and H. Dai “Shape-regulation: An effective way to control CO oxidation activity over noble metal catalysts” Catal. Today, vol. 201, no.1, pp. 68– 78, 2013.

[8] J. Feng, X-Y Ma, Yu-Fei He, D. G. Evans, D. Li “Synthesis of hydrotalcite-supported shape-controlled Pd nano particles by a precipitation–reduction method” Appl. Catal., A, vol. 413-414, pp.10– 20, 2012.

[9] Li-J. Chen, C-C. Wan, Y-Y. Wang, “Chemical preparation of Pd nanoparticles in room temperature ethylene glycol system and its application to electroless copper deposition”J. Colloid Interface Sci., vol. 297, No.2, pp. 143–150 , 2006.

[10] J. I. Rima, A. E. D. Holly, O. Emil, L. Leonardo, V. Philippe, A. B. Elena, “Metal-Support Interaction of Pt Nanoparticles with Ionically and Non-Ionically Conductive Supports for CO Oxidation” Electrochem. Solid—State Lett. 15(3), E14-E17, 2012.

[11] Y. Xiong, H. Cai, B.J. Wiley, J. Wang, M.J. Kim, Y. Xia, “Synthesis and Mechanistic Study of Palladium Nanobars and Nanorods” J. Am. Chem. Soc., 129, 3665-3675, 2007.

[12] W. Zheng, J. Qu, X. Hong, K.Tedsree and S.C. E. Tsang “Probing the Size and Shape Effects of Cubic- and Spherical-Shaped Palladium Nanoparticles in the Electrooxidation of Formic Acid” ChemCatChem., vol.7, pp. 3826 – 3831, 2015.