First time-resolved EPR observation of Nafion photochemistry.

نویسندگان

  • Fosca Conti
  • Enrico Negro
  • Vito Di Noto
چکیده

Time-resolved EPR spectra of UV-irradiated Nafion reveal the formation of spin-polarized excited triplet states and allow the detection of photoinduced triplet-triplet energy transfer processes through hydrogen bonds between water and sulfonic acid groups.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Optical and electron paramagnetic resonance studies of the excited triplet states of UV-B absorbers: 2-ethylhexyl salicylate and homomenthyl salicylate.

The energy levels and lifetimes of the lowest excited triplet (T1) states of UV-B absorbers, 2-ethylhexyl salicylate (EHS) and homomenthyl salicylate (HMS), and their deprotonated anions (EHS(-) and HMS(-)) were determined through measurements of phosphorescence and electron paramagnetic resonance (EPR) spectra in rigid solutions at 77 K. The observed T1 energies of EHS and HMS are higher than ...

متن کامل

Time-Resolved EPR: A Novel Method For Studying Living Chains

Despite its great industrial importance, many aspects of free radical polymerization (FRP)1 remain poorly understood. One of the few methods that can directly probe propagating radicals, i.e., living chains which are at the heart of FRP, is electron paramagnetic resonance (EPR), a very sensitive and nondestructive technique that provides information on the local structure and dynamics and the n...

متن کامل

First observation of the hyperfine structure of an excited quintet state in liquid solution.

After pulsed photoexcitation of a new fullerene-linked bisnitroxide, a well resolved transient EPR spectrum is detected which is assigned to an excited quintet spin state generated by spin coupling of the nitroxides and the fullerene excited triplet.

متن کامل

Direct observation of an isopolyhalomethane O-H insertion reaction with water: picosecond time-resolved resonance Raman (ps-TR3) study of the isobromoform reaction with water to produce a CHBr2OH product.

Picosecond time-resolved resonance Raman (ps-TR3) spectroscopy was used to obtain the first definitive spectroscopic observation of an isopolyhalomethane O-H insertion reaction with water. The ps-TR3 spectra show that isobromoform is produced within several picoseconds after photolysis of CHBr3 and then reacts on the hundreds of picosecond time scale with water to produce a CHBr2OH reaction pro...

متن کامل

Time-resolved photothermal methods: accessing time-resolved thermodynamics of photoinduced processes in chemistry and biology.

Photothermal methods are currently being employed in a variety of research areas, ranging from materials science to environmental monitoring. Despite the common term which they are collected under, the implementations of these techniques are as diverse as the fields of application. In this review, we concentrate on the recent applications of time-resolved methods in photochemistry and photobiol...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Chemical communications

دوره 45  شماره 

صفحات  -

تاریخ انتشار 2009