PCCP Blog

PCCP ‘HOT’ article – Exposure to humidity leads to metal ion concentrations of up to one per 4.7 polymer units

The stability of a common interface used in organic photovoltaic cells, between the transparent electrode of Indium Tin Oxide (ITO) and the polymer buffer layer (PEDOT:PSS) is strongly influenced by the presence of humidity during processing. This leads to significant migration of indium and tin species into the PEDOT:PSS layer.

Role of humidity on indium and tin migration in organic photovoltaic devices
Anirudh Sharma, Gunther Andersson and David A. Lewis
Phys. Chem. Chem. Phys., 2011, DOI: 10.1039/C0CP02203A

Canadian scientists have, for the first time, been able to identify spectroscopically carbon dioxide clusters that could provide valuable information on intermolecular interactions.

Despite the significance of carbon dioxide in atmospheric chemistry and use of supercritical carbon dioxide as an industrial solvent, the spectroscopic identification and study of carbon dioxide clusters have so far been limited to the dimer and trimer, as larger clusters can break up when being analysed.

Now, Robert McKellar and his team at the University of Calgary and the Steacie Institute for Molecular Sciences, Ontario, have identified (CO₂)₆ to (CO₂)₁₃ clusters using high resolution infrared (IR) spectroscopy, as published in their latest PCCP paper.

‘Studying clusters is a very good way of getting a handle on that because if we build up the cluster and measure its properties, then we’re really learning about the intermolecular forces in a direct way,‘ says McKellar.

Read the rest of the Chemistry World article by Yuandi Li…

Read the PCCP article:
Spectroscopic identification of carbon dioxide clusters: (CO2)6 to (CO2)13
J. Norooz Oliaee, M. Dehghany, N. Moazzen-Ahmadi and A. R. W. McKellar
Phys. Chem. Chem. Phys., 2011, 13, 1297-1300

‘HOT’ Perspective feature article – catalytic MOFs

This feature article summarises the unique properties of metal–organic frameworks (MOFs) and discusses their potential as catalysts.

The authors explore the idea that MOFs have the potential to catalyze any number of new reactions:

“We experience a unique opportunity to imagine and design heterogeneous catalysts, which might catalyze reactions previously thought impossible.”

Catalysis by metal–organic frameworks: fundamentals and opportunities
Marco Ranocchiari and Jeroen Anton van Bokhoven
Phys. Chem. Chem. Phys., 2011, DOI: 10.1039/C0CP02394A

They categorise three classes of MOF catalysts:

1. those with active site on the framework
2. those with encapsulated active species
3. those with active sites attached through post-synthetic modification

The authors also identify the unique characteristics that distinguish MOFs from other materials:

• tunable porosity
• the ability to fine tune the structure of the active site and its environment
• the presence of multiple active sites
• the opportunity to synthesize structures in which key–lock bonding of substrates occurs