15:30-16:15

Conjugated Polyelectrolytes: Fundamentals, Layer-by-Layer Films and Solar Cell Applications

Conjugated polyelectrolytes (CPEs) are organic polymers that feature a pi-conjugated backbone that is substituted with ionic solubilizing groups. These polyfunctional materials exhibit responsive optical properties such as strong visible light absorption, coupled with the properties typical of polyelectrolytes, i.e., water solubility, surface activity and interaction with oppositely charged ions in solution. We have studied the solution properties of CPEs, focusing on their propensity to self-assemble into colloidal aggregates in water, and the interplay between the solution properties and the optical properties of the conjugated backbone. This talk will summarize fundamental work on CPEs, with emphasis on layer-by-layer films and application of CPE films in organic and hybrid solar cells.

Lead Reference:

1. Jiang, H.; Taranekar, P.; Reynolds, J. R.; Schanze, K. S., “Conjugated Polyelectrolytes: Synthesis, Photophysics and Applications”, *Angew. Chem. Int. Ed. Engl.* *2009*, *48*, 4300-4316 (invited review article).

Speaker

Kirk S. Schanze, Editor-in-Chief, ACS Applied Materials & Interfaces, Chairman, Organic Chemistry Division, University of Florida, USA

Chair

Katsuhiko Ariga, MANA PI, MANA, NIMS

16:15-16:45

Optimization of Piezoresistive Cantilever Sensors towards Highly Sensitive Membrane-type Surface Stress Sensor (MSS)

We present a membrane-type surface stress sensor (MSS), which consists of an “adsorbate membrane” suspended by four piezoresistive “sensing beams,” composing a full Wheatstone bridge. It allows efficient transduction of analyte-induced stress. A prototype MSS demonstrates a high sensitivity (>×20 than a standard piezoresistive cantilever; comparable with optical methods; can be enhanced further). Given the various conveniences and advantages of the integrated piezoresistive read-out and CMOS compatibility, this platform is expected to open a new era of sensors for the real-time and label-free detection from gaseous to biological molecules in medical, security, and environmental applications.

Speaker

Genki Yoshikawa, ICYS-MANA Researcher, NIMS

Chair

Masakazu Aono, MANA PI, MANA, NIMS