Self-Reporting Conjugated Polymer Nanoparticles for Superoxide Generation and Detection.

Conjugated polymer nanoparticles (CPNs or Pdots) have become increasingly popular fluorophores for multimodal applications that combine imaging with phototherapeutic effects. Reports of CPNs in photodynamic therapy applications typically focus on their ability to generate singlet oxygen. Alternatively, CPN excited states can interact with oxygen to form superoxide radical anion and a CPN-based hole polaron, both of which can have deleterious effects on fluorescence properties.

Direct observation of bicarbonate and water reduction on gold: understanding the potential dependent proton source during hydrogen evolution.

The electrochemical conversion of CO represents a promising way to simultaneously reduce CO emissions and store chemical energy. However, the competition between CO reduction (COR) and the H evolution reaction (HER) hinders the efficient conversion of CO in aqueous solution. In water, CO is in dynamic equilibrium with HCO, HCO , and CO .

Comparing interfacial cation hydration at catalytic active sites and spectator sites on gold electrodes: understanding structure sensitive CO reduction kinetics.

Hydrated cations present in the electrochemical double layer (EDL) are known to play a crucial role in electrocatalytic CO reduction (COR), and numerous studies have attempted to explain how the cation effect contributes to the complex COR mechanism. COR is a structure sensitive reaction, indicating that a small fraction of total surface sites may account for the majority of catalytic turnover. Despite intense interest in specific cation effects, probing site-specific, cation-dependent solvation structures remains a significant challenge.

The Solvation-Induced Onsager Reaction Field Rather than the Double-Layer Field Controls CO Reduction on Gold.

The selectivity and activity of the carbon dioxide reduction (COR) reaction are sensitive functions of the electrolyte cation. By measuring the vibrational Stark shift of in situ-generated CO on Au in the presence of alkali cations, we quantify the total electric field present at catalytic active sites and deconvolute this field into contributions from (1) the electrochemical Stern layer and (2) the Onsager (or solvation-induced) reaction field. Contrary to recent theoretical reports, the COR kinetics does not depend on the Stern field but instead is closely correlated with the strength of the Onsager reaction field.