Hydrogen can be used as an energy carrier for renewable energy to overcome the deficiency of its intrinsically intermittent supply. One of the most promising application of hydrogen energy is on‐board hydrogen fuel cells. However, the lack of a safe, efficient, convenient, and low‐cost storage and transportation method for hydrogen limits their application. The feasibility of mainstream hydrogen storage techniques for application in vehicles is briefly discussed in this Review. Formic acid (FA), which can reversibly be converted into hydrogen and carbon dioxide through catalysis, has significant potential for practical application. Historic developments and recent examples of homogeneous noble metal catalysts for FA dehydrogenation are covered, and the catalysts are classified based on their ligand types. The Review primarily focuses on the structure−function relationship between the ligands and their reactivity and aims to provide suggestions for designing new and efficient catalysts for H2 generation from FA.

Formic acid (FA) is considered to be a potential hydrogen storage material. Homogeneous catalysts are desired, which decompose aqueous FA into H 2 and CO 2 without addition of organic additives as they can contaminate the generated gas mixture. We report a new series of Cp*Ir (Cp* = pentamethylcyclopentadienyl) catalysts featuring picolinamide-based ligands for efficient H 2 generation from FA solution. Among them in-situ generated catalyst from [Cp*Ir(H 2 O) 3 ]SO 4 and picolinohydroxamic acid (L3) achieved a high turnover frequency (TOF) of 90625 h À 1 at 80 °C in 0.9 M FA solution and a turnover number (TON) of 120520 at 80 °C in a recycle experiment. The substituent effect of amide N atom was discussed and a plausible mechanism was proposed based on the experimental results.