The paper by Nørskov et al. (2005) investigates the trends in the exchange current for hydrogen evolution, a critical electrochemical reaction. The authors use a density functional theory (DFT) database to calculate hydrogen chemisorption energies on various transition and noble metals. They plot these energies against measured exchange currents, revealing a "volcano curve" where the most efficient catalysts for hydrogen evolution are located at the peak. The volcano curve is explained through a simple kinetic model, which shows that the reaction is thermo-neutral on platinum (Pt), making it the most efficient catalyst. The study also discusses the impact of water dissociation on the surface and concludes that the correlation between chemisorption energies and exchange currents is significant, with Pt being the optimal catalyst for hydrogen evolution.The paper by Nørskov et al. (2005) investigates the trends in the exchange current for hydrogen evolution, a critical electrochemical reaction. The authors use a density functional theory (DFT) database to calculate hydrogen chemisorption energies on various transition and noble metals. They plot these energies against measured exchange currents, revealing a "volcano curve" where the most efficient catalysts for hydrogen evolution are located at the peak. The volcano curve is explained through a simple kinetic model, which shows that the reaction is thermo-neutral on platinum (Pt), making it the most efficient catalyst. The study also discusses the impact of water dissociation on the surface and concludes that the correlation between chemisorption energies and exchange currents is significant, with Pt being the optimal catalyst for hydrogen evolution.