Saturday, December 19, 2015

How to ALD in Metal-Organic Framworks (MOFs) using Ultratech/CNT Savannah

Here is a fresh open source publication on a rather hot topic - using ALD in Metal-Organic Framworks (MOFs). It is really a fantastic publication giving step by step detailed instructions how to perform the materials synthesis. The researchers come from Northwestern University, Argonne National Laboratory and King Abdulaziz University. They are using ALD to deposit into the extremely well defined porous material. The ALD processing is performed in the popular Ultratech/Cambridge Nanotech Savannah reactor using a grid powder holder (see description below). Some of the researchers are involved in a startup company, NuMat Technologies, which is seeking to commercialize metal-organic frameworks.

 
Background:  MOFs are a class of crystalline materials that have a well-defined and atomically precise structures, exceptional porosities and the tunability of : 
  • particle size
  • pore size
  • surface area
  • density
  • topology
  • molecular affinity 
Beacuse of these exceptional properties MOFs are being investigated for a broad range of applications like: 
  • gas storage 
  • gas separation
  • heterogeneous catalysis
  • sensing
  • light harvesting
  • drug delivey 
Please check for all the details in the open-source publication below and real all the details:

Scalable synthesis and post-modification of a mesoporous metal-organic framework called NU-1000

Timothy C Wang,    Nicolaas A Vermeulen, In Soo Kim, Alex B F Martinson, J Fraser Stoddart, Joseph T Hupp & Omar K Farha  

Nature Protocols, 11, 149–162 (2016) doi:10.1038/nprot.2016.001

The synthesis of NU-1000, a highly robust mesoporous (containing pores >2 nm) metal-organic framework (MOF), can be conducted efficiently on a multigram scale from inexpensive starting materials. Tetrabromopyrene and (4-(ethoxycarbonyl)phenyl)boronic acid can easily be coupled to prepare the requisite organic strut with four metal-binding sites in the form of four carboxylic acids, while zirconyl chloride octahydrate is used as a precursor for the well-defined metal oxide clusters. NU-1000 has been reported as an excellent candidate for the separation of gases, and it is a versatile scaffold for heterogeneous catalysis. In particular, it is ideal for the catalytic deactivation of nerve agents, and it shows great promise as a new generic platform for a wide range of applications. Multiple post-synthetic modification protocols have been developed using NU-1000 as the parent material, making it a potentially useful scaffold for several catalytic applications. The procedure for the preparation of NU-1000 can be scaled up reliably, and it is suitable for the production of 50 g of the tetracarboxylic acid containing organic linker and 200 mg–2.5 g of NU-1000. The entire synthesis is performed without purification by column chromatography and can be completed within 10 d.






Structure of NU-1000 and developed post-synthetic modification methods on this platform. The blue, red and black spheres represent zirconium, oxygen and carbon, respectively. The perfluoro alkane SALIed into NU-1000 is represented in green, and the gold sphere shows the location of a metal cluster introduced into NU-1000 using AIM. [doi:10.1038/nprot.2016.001 Nature Publishing Group, Licence number 3772371203825]



Equipment setup for 250-mg-scale AIM modification for Al-AIM. (a,b) The metal screen constituting the power holder (a) and the reaction chamber of the ALD instrument (b). 
[doi:10.1038/nprot.2016.001 Nature Publishing Group, Licence number 3772371203825]