ELECTROCATALYSTS FOR OXYGEN-AND HYDROGEN-INVOLVING ENERGY CONVERSION REACTIONS

摘要

Among various means for energy conversion, fuel cells and water splitting are of great importance because they can directly convert chemical energy to electricity or fuel with much higher efficiency and lower greenhouse gases emissions than other well-established technologies based on conventional fossil fuel combustion. However, such promising devices and processes always require noble metal catalysts, such as Pt or Ir, to facilitate low overpotential and fast kinetics of their sluggish partial reactions (such as oxygen reduction reaction, oxygen evolution reaction and hydrogen evolution reaction) for practical applications. It is a tremendous challenge to find new generation non-precious metal alternatives with reduced cost, enhanced stability, and high efficiency properties for sustainable clean energy generation. Concerning these issues, we have successfully designed and developed a series of cost-effective carbon-based non-precious metallic and non-metallic electrocatalysts (meso/micro carbons, doped graphenes and graphitic carbon nitride etc.) for these key energy conversion reactions with high performances and durable stability. With the assistance of density functional theory (DFT) calculation, we can fundamentally provide clear evidence that, similar to precious metals, the well-designed non-precious metals and metal-free counterparts have also a great potential for highly efficient electrocatalytic energy conversion reactions, thus opening a new avenue towards replacing noble metals by broader alternatives in a wide variety of applications.