A Viable Hydrogen-Storage System Based On Selective Formic Acid Decomposition with a Ruthenium Catalyst

摘要

Hydrogen represents an important alternative energy feedstock for both environmental and economic reasons,and when combined with fuel-cell technology,very efficient energy conversion can be achieved.Although the advantages of hydrogen over fossil fuels are numerous,the actual use of hydrogen as a transportation fuel is limited mainly because of storage and delivery problems.Conventional hydrogen-storage methods,such as high-pressure gas containers and cryogenic liquid/gas containers,have weight and safety issues.Consequently,a great deal of research is being undertaken to develop new materials,such as metal hydrides and carbon nanostructures,that store hydrogen efficiently,although no entirely satisfactory options have been found so far.Formic acid containing 4.4 wt% of hydrogen,as well as its conjugate base,formate salt,are well known sources of hydrogen and have previously been reported as potential hydrogen-storage material.Formic acid has the advantage over other substrates that only gaseous products are formed (H2/CO2),hence preventing the accumulation of by-products,which is a limitation for mobile applications.However,until now potential applications have been limited by catalyst regeneration requirements,by harsh reaction conditions,and by poor selectivity.We present herein an efficient,completely selective,and robust system for hydrogen production from formic acid using water-soluble homogeneous catalysts.