Insight investigation about the origin of activity of single atom N-doped graphene electro catalyst for hydrogen evolution reaction

The world becomes getting warmer day by day due to extensive use of fossil fuels in primary energy mixture for energy production. As an alternative sustainable energy source, molecular hydrogen production through electrolytic reduction of water via hydrogen evolution reaction (HER) is a stronger candidate. Among all catalyst, platinum is the most efficient but the excessive cost and non-availability limits its industrial production of hydrogen. As an alternative of platinum now researchers are focused on single atom catalysis (SAC) with a fraction amount of transition metals supported by effective supporting materials. Here we report evaluation a series of transition metals based single atom catalysts supported by N-doped graphene by combining electrochemical measurement and density functional theory calculation. We find upper transitional metals coordinated with N show better activity towards HER than the post transitional metals. Also, we able to establish an activity trends with most active hybridized orbital of M-N₄ and antibonding states resulting from H-interaction with adsorbent. So, we think that by theoretically predicted electronic properties and experimentally achieved electrochemical activity will open a new era to design highly efficient electro catalysts for HER.