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Driving ethanol electrooxidation in fuel cells is a promising technology for realizing the effective conversion of biomass energy into renewable electrical energy. However, it is still a challenge to broaden the application of fuel cells due to the limitation of effective electrocatalysts. Herein, we have proposed the design and synthesis of an advanced nonmetal-doped Pd nanocrystal catalyst for promoting the electrocatalytic ethanol oxidation reaction (EOR), in which the incorporation of nonmetal Te not only effectively modifies the electronic structure of Pd to enhance the intrinsic activity of the catalyst but also significantly boosts the further oxidation of intermediates, thereby promoting the electrocatalytic properties. Significantly, a mass activity of 1203 mA mgPd−1 for the optimized PdTe nanocrystals (NCs) has been realized, which is 4.7- and 2.5-fold enhancements as compared to the Pd NCs (255.4 mA mgPd−1) and commercial Pd/C (485 mA mgPd−1), respectively, presenting a promising electrocatalyst for fuel cells. [ABSTRACT FROM AUTHOR]

Self-targeting antimicrobial platforms have yielded new possibilities for the treatment of infectious biofilms. Self-targeting involves stealth transport through the blood circulation towards an infectious biofilm, where the antimicrobial platform penetrates and accumulates in a biofilm in response to a change in environmental conditions, such as local pH. In a final step, nano-antimicrobials need to be activated or the antimicrobial cargo of nanocarriers released. Zwitterions possess both cationic and anionic groups, allowing full reversal in zeta potential from below to above zero in response to a change in environmental conditions. Electrolyte-based platforms generally do not have the ability to change their zeta potentials from below to above zero. Zwitterions for use in self-targeting platforms are usually hydrophilic and have a negative charge under physiological conditions (pH 7.4) providing low adsorption of proteins and assisting blood circulation. However, near or in the acidic environment of a biofilm, they become positively-charged yielding targeting, penetration and accumulation in the biofilm through electrostatic double-layer attraction to negatively-charged bacteria. Response-times to pH changes vary, depending on the way the zwitterion or electrolyte is built in a platform. Self-targeting zwitterion-based platforms with a short response-time in vitro yield different accumulation kinetics in abdominal biofilms in living mice than platforms with a longer response-time. In vivo experiments in mice also proved that self-targeting, pH-responsive zwitterion-based platforms provide a feasible approach for clinical control of bacterial infections. Clinically however, also other conditions than infection may yield an acidic environment. Therefore, it remains to be seen whether pH is a sufficiently unique recognition sign to direct self-targeting platforms to an infectious biofilm or whether (additional) external targeting through e.g. near-infrared irradiation or magnetic field application is needed. [ABSTRACT FROM AUTHOR]