Fuel cells articles from across Nature Portfolio

The activation barriers of interfacial energy conversion reactions are key to controlling the efficiency of electrolysers. Work on the structural dynamics of water during charge transfer at electrified solid/liquid interfaces now brings greater understanding of the components of the activation barriers for water dissociation and hydrogen evolution.

Phosphoric acid (PA) doped proton exchange membranes (PEMs) often degrade above 200 °C due to membrane creeping, PA dehydration, and condensation. Here, the authors introduce gel-state polybenzimidazole PEMs with double cross-linked 3D layered structures, enabling efficient and stable fuel cell operation above 200 °C.

The synthesis of well-defined heterostructure interfaces can be leveraged to design advanced catalysts. Now a catalyst consisting of carbon-supported Janus particles with crystalline Ru and amorphous CrO_x sides is shown to achieve high performance for both alkaline hydrogen oxidation and evolution reactions due to the synergy between both sides.

Improving materials for energy devices relates to an optimisation of their surfaces. Here authors show that surface modification with ultrathin oxide layers allows for a tailoring of the surface dipole and the work function of mixed ionic and electronic conducting oxides.

The electrochemical oxygen reduction reaction plays an important role in new energy technologies such as fuel cells and metal-air batteries. Here the authors present a cobalt catalyst with a symmetry-broken Cl−Co−N₄ moiety capable of dynamically modulating electron occupancy at active sites during practical reaction conditions to optimize oxygen reduction performance.

The activation barriers of interfacial energy conversion reactions are key to controlling the efficiency of electrolysers. Work on the structural dynamics of water during charge transfer at electrified solid/liquid interfaces now brings greater understanding of the components of the activation barriers for water dissociation and hydrogen evolution.

Oxygen electrocatalysis is key for energy conversion and storage technologies such as fuel cells and water electrolysers. However, the measurement of the performance of electrocatalysts is not standardized. This Comment addresses emerging pitfalls in performance evaluation and discusses best practices for oxygen electrocatalysis.

Iron–nitrogen–carbon (FeNC) catalysts are a viable alternative to platinum, but still lack the necessary performance. Now, pyrolysis under forming gas is found as a path to boosting their site density, activity and durability.

Bipolar membranes are emerging as an enabling component in numerous energy-relevant electrochemical devices, but a greater understanding of how they operate in complex electrolytes is needed. Research now reveals that ionic species in mixed-ion electrolytes can block the heart of the membrane, the bipolar junction, hampering its performance.

Protonic ceramic electrochemical cells (PCECs) have the potential to operate below 450 °C, but their performance is poor at such temperatures. Through the development of a low-resistance electrolyte and the in situ formation of a composite positive electrode, a PCEC with good fuel cell and electrolysis cell performance at <450 °C is demonstrated.