简介: |
NANOPOROUS MATERIALS FOR DELIVERY AND METAL-FREE CATALYSIS
Shizhang Qiao
School of Chemical Engineering, The University of Adelaide, SA5005, Australia
Based on theoretical prediction [1], we developed a nanoporous g-C3N4@CMK-3 (CMK-3 represents 2D ordered mesoporous carbon) metal-free catalyst as a new generation efficient cathode catalyst for oxygen reduction reaction (ORR). This novel metal-free electrocatalyst exhibited competitive ORR catalytic activity as compared to the commercial Pt/C catalyst. Moreover, it showed a near 100% selectivity in four-electron oxygen reduction path, demonstrating its excellent electrocatalytic efficiency [1]. Besides 2D mesostructure, we further designed a macroporous g-C3N4/C electrode with 3D interconnected structure for ORR with fast electrochemical kinetics [2]. Apart from the excellent electrocatalytic activity, the macroporous g-C3N4/C electrode also featured much better long term stability and superior methanol tolerance in the alkaline solution as compared to Pt/C catalyst. The interconnected macropores in the composite not only facilitated the ORR process by enhancing reactants’ mass transport but also elevated the stability because of stronger 3D framework [1,2].
We also developed a general and facile template strategy for the fabrication of a new class of nano-structured materials, the so-called yolk-shell structured materials with movable cores and porous shells [3]. Our approach is demonstrated by encapsulating silica spheres, mesoporous silica nano-particles, Au particles, magnetic particles and Au@SiO2 nano-particles in porous silica shell [3]. The hierarchical mesoporous yolk-shell structures were obtained for the first time by encapsulating mesoporous silica nano-particles into the mesoporous silica shell. We also report recent research progress in the synthesis and bio-applications of magnetic mesoporous materials [4,5]. In our research, we used self-assembly method to prepare the composites of Fe3O4 nanocrystals and highly ordered periodic mesostructured silicas with various morphologies including nanospheres, hollow spheres and helical rods. Our studies reveal that these magnetic mesoporous materials have highly effective and selective separation features for different size bio-molecules and excellent delivery performances for drugs and DNA [6-8].
We will also summarize some research progresses in our group in the preparation of the mesoporous materials with controlled morphologies, surface chemistry, composition, particles sizes and pore sizes and their applications as catalysts, adsorption and clean energy [9-12].
References:
[1] Y. Zheng, Y. Jiao, J. Chen, J. Liu, J. Liang, A. Du, W. Zhang, Z. Zhu, S. C. Smith, M. Jaroniec, G. Q. Lu, S. Z. Qiao, J. Am. Chem. Soc. 133 (2011) 20116
[2] J. Liang, Y. Zheng, J. Chen, J. Liu, D. Hulicova-Jurcakova, M. Jaroniec, S. Z. Qiao, Angew. Chem. Int. Ed., 51 (2012) 3892
[3] J. Liu, S.Z. Qiao, et al, Angew. Chem. Int. Ed. 49 (2010) 4981
[4] L. Zhang, S.Z. Qiao, et al., Advanced Materials 20 (2008) 805
[5] L. Zhang, S.Z. Qiao, et al., Advanced Functional Materials 18 (2008) 3203.
[6] J. Liu, S.Z. Qiao, et al., Small 7 (2011) 425
[7] J. Liu, B. Wang, S. Budi Hartono, T. Liu, P. Kantharidis, A. Middelberg, G.Q. Lu, L. He, S.Z. Qiao, Biomaterials 33 (2012) 970
[8] S. Budi Hartono, W.Y. Gu, F. Kleitz, J. Liu, L. He, A. Middelberg, C. Yu, G.Q. Lu, S.Z. Qiao, ACS Nano 6 (2012) 2104
[9] J. Liu, S.Z. Qiao, et al, Angew. Chem. Int. Ed. 50 (2011) 5947
[10] C.Y. Ma, Z. Mu, J. Li, Y. Jin, J. Cheng, G.Q. Lu, Z.P. Hao, S.Z. Qiao, Journal of the American Chemical Society 132 (2010) 2608
[11] G. Wang, H. Liu, J. Liu, S. Z. Qiao, G. G. Lu, P. Munroe, Advanced Materials 22 (2010) 4944 [12] Y. Zheng, Y. Jiao, M. Jaroniec, Y. Jin, S. Z. Qiao, Small 8 (2012), in press.
Biography of Prof Shizhang Qiao (乔世璋)
Shi-Zhang Qiao received his PhD degree in chemical engineering from Hong Kong University of Science and Technology in 2000, and is currently a professor (Chair of Nanotechnology) at School of Chemical Engineering of the University of Adelaide, and an Honorary Professor at AIBN of The University of Queensland, Australia. His research expertise is in nanomaterials and nanoporous materials for bioseparations, drug/gene delivery and new energy technologies. He has co-authored more than 135 papers in refereed journals, including Nature, JACS, Angew. Chem., Adv. Mater., and has filed several patents on novel nanomaterials that are promising for drug/gene delivery, fuel cells, photocatalysis and solar cells.
Contact Details：
Prof. Shizhang Qiao
School of Chemical Engineering
The University of Adelaide
Adelaide, SA 5005, Australia
Email: s.qiao@adelaide.edu.au
|
