Silver in the linings The bacterium Shewanella oneidensis is well known to use extracellular electron sinks, metal oxides and ions in nature or electrodes when cultured in a fuel cell, to power the catabolism of organic material. However, the power density of microbial fuel cells has been limited by various factors that are mostly related to connecting the microbes to the anode. Cao et al . found that a reduced graphene oxide–silver nanoparticle anode circumvents some of these issues, providing a substantial increase in current and power density (see the Perspective by Gaffney and Minteer). Electron microscopy revealed silver nanoparticles embedded or attached to the outer cell membrane, possibly facilitating electron transfer from internal electron carriers to the anode. —MAF

Alkaline direct alcohol fuel cells (ADAFCs) represent an attractive alternative to hydrogen fuel cells for the more convenient storage, transportation, and lower cost of alcohols (e.g., methanol and ethanol) when compared with compressed hydrogen. However, the anode alcohol oxidation reaction (AOR) is generally plagued with high overpotential and sluggish kinetics, and often requires noble metal-based electrocatalysts to accelerate the reaction kinetics. To this end, the development of efficient AOR electrocatalysts with high mass activity (MA), high durability, high Faradaic efficiency (FE), and low overpotential is central for realizing practical ADAFCs. Here, in this minireview, a brief introduction of the fundamental challenges associated with AOR in alkaline electrolyte, the key performance metrics, and the evaluation protocols for benchmarking AOR electrocatalysts are presented, followed by a summary of the recent advances in the noble-metal based AOR electrocatalysts (e.g., Pt, Pd, and Rh) with an emphasis on the design criteria for improving the specific activity and electrochemical surface area to ultimately deliver high MA while at the same time ensuring long term durability. The strategies to enhance FE and lower overpotential will also be discussed. Last, it is concluded with a brief perspective on the key challenges and future opportunities.

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Hydrazine‐assisted water electrolysis offers a feasible path for low‐voltage green hydrogen production. Herein, the design and synthesis of ultrathin RhRu0.5‐alloy wavy nanowires as bifunctional electrocatalysts for both the anodic hydrazine oxidation reaction (HzOR) and the cathodic hydrogen evolution reaction (HER) is reported. It is shown that the RhRu0.5‐alloy wavy nanowires can achieve complete electrooxidation of hydrazine with a low overpotential and high mass activity, as well as improved performance for the HER. The resulting RhRu0.5 bifunctional electrocatalysts enable, high performance hydrazine‐assisted water electrolysis delivering a current density of 100 mA cm−2 at an ultralow cell voltage of 54 mV and a high current density of 853 mA cm−2 at a cell voltage of 0.6 V. The RhRu0.5 electrocatalysts further demonstrate a stable operation at a high current density of 100 mA cm−2 for 80 hours of testing period with little irreversible degradation. The overall performance greatly exceeds that of the previously reported hydrazine‐assisted water electrolyzers, offering a pathway for efficiently converting hazardous hydrazine into molecular hydrogen.