Supervisor: Dr. Marijn van Huis
Promotor: Prof. dr. Alfons van Blaaderen
Funding: Sectorplan UU/EU MC
Employed: 15 February 2016 till 14 February 2020

Synthesis and Characterization of Nanocrystals and in-situ Monitoring Self-Assembly

Noble metals nanocrystals (NMNCs) are promised in wide application fields, such as catalysis, energy, sensor and biomedicine, due to their specific properties.[1] The functions of NMNCs highly rest upon their constituents, sizes, morphologies, internal and surficial structures.[2, 3] Notably, self-assembly (SA) of NMNCs is an effective method for improving performance and extending applied range and provides insight of crystal growth and bridge for materials design between  nanoscale and macroscale.

In this work, NMNCs, eg. gold nanotriangles⁴ and multi-metal nanocrystals (figure 1),  are used as building blocks for SA into one-dimension (1D) stacks, two-dimension (2D) superlattices and three-dimension (3D) superballs.^5,6 The  advanced Transmission Electron Microscope (TEM) technics, including high resolution transmission electron microscope (HRTEM), high angle annular dark field scanning transmission electron microscope (HAADF-STEM), (S)TEM-tomography, energy-dispersive X-ray spectroscopy (EDS), electron diffraction, in-situ heating TEM and liquid-cell TEM, are engaged in micro-structures, elemental analysis, 3D reconstruction, shape evolution, crystal growth and SA process study. The application of as-prepared materials will be used for surface enhanced Raman scattering (SERS) and catalysis.

Figure 1. HAADF-STEM images of NMNCs: A) Au nanotriangles. B),C),D) shape evolution of Au/Ag/Pt heterogeneous nanostructures.

[1] Cortie, M. B. et al. Chem. Rev. 2011, 111, (6), 3713-35.

[2] Ferrando, R. et al. Chem. Rev. 2008, 108, 845-910.

[3] Xie, X., et al., Adv. Mater. 2015, 27, (37), 5573-7.

[4] Scarabelli. L., et al. ACS Nano, 2014, 8(6): 5833–5842.

[5] H.R.Vutukuri, et al. Nano Lett., 2015, 15 (8), pp 5617–5623.

[6] B. de Nijs, et al. Nat. Mater.2015, 14, 56-60.