Tuning proton conductivity and energy barriers for proton transfer

Proton transport is critical for many technologies and a variety of biochemical biophysical processes. transfer between molecules (via structural diffusion) considered to be an efficient mechanism in highly proton conducting materials. Yet, the what controls energy barriers this process remain poorly understood. It was shown that mixing phosphoric acid (PA) with lidocaine leads increase conductivity at same liquid viscosity. However, recent simulations mixtures PA various bases, including lidocaine, suggested no decrease barrier. To elucidate surprising result, we have performed broadband dielectric spectroscopy verify predictions several bases. Our results reveal adding bases increases transfer, observed similar viscosity appears related glass transition temperature (Tg) mixture. Moreover, barrier seems Tg mixtures, emphasizing importance molecular mobility or interactions mechanism.