Project TitleNon-Transition Metal Electrocatalysts for Hydrogen Evolution and Hydrogen Oxidation Reactions (16082)
Track Code16082
Short DescriptionNone

Non-Transition Metal Electrocatalysts for Hydrogen Evolution and Hydrogen Oxidation Reactions (16082)


Features and Benefits

  • Innovative substitution for metal-hydride intermediates

  • Highly modifiable—capable of being engineered with different functional groups for various applications

  • Air and water stable—no special precautions in preparation, storage or handling

  • Low molecular weights reduce mass of catalysts

  • Does not utilize precious or semi-precious metals for catalysts

 *This Technology is available for licensing, further development, or industrial partnering*



University of Louisville researchers are developing an innovative pathway for homogenous electrocatalytic H2 evolution and H2 oxidation utilizing a redox active thiosemicarbazone and its zinc complex as seminal metal-free and transition metal-free examples. The non-transition metal complex ZnL and the metal-free ligandH2L represent a fundamentally new class of homogeneous HER and HOR electrocatalysts. Unlike traditional catalysts that employ a metal-hydride as the key intermediate, this new approach facilitates H2 evolution through ligand-centered radical coupling. Diacetyl-bis(N-4-methyl-3-thiosemicarbazone) and zinc diacetyl-bis(N-4-methyl-3-thiosemicarbazide) display the highest reported TOFs of any homogeneous ligand-centered H2 evolution catalyst, 1320 s-1 and 1170 s-1 respectively, while the zinc complex also displays one of the highest reported TOF values for H2 oxidation, 72 s-1, of any homogeneous catalyst.  Catalysis proceeds via ligand-centered proton-transfer and electron-transfer events while avoiding traditional metal-hydride intermediates. The unique mechanism is consistent with electrochemical results, and is further supported by density functional theory.        

Figure 1

(A) Structure of zinc-diacetyl-bis(N-4-methylthiosemicarbazone), ZnL, with a weakly coordinating solvent molecule (yellow-green) in the axial position. (Zn dark green, S yellow, N blue, C gray, H light gray). 

(B) Structure of diacetyl-bis(N-4-methylthiosemicarbazone), H2L (S yellow, N blue, C gray, H light gray).


Market Opportunities

Hydrogen serves as a promising alternative carbon-free fuel and is an essential building block for industrial and agricultural processes.  Existing techniques for industrial H2 production, however, are environmentally unstainable and/or cost prohibitive.  This technology allows for a renewable and cost effective approach for industrial hydrogen evolution.  In addition, these novel catalysts are highly modifiable, air and water stable, and have low molecular weights. 


Technology Status

  • IP Status: Patent Pending
  • Development Status: Proof of Concept Demonstrated
  • Publications: "Beyond Metal-Hydrides: Non-Transition-Metal and Metal-Free Ligand-Centered Electrocatalytic Hydrogen Evolution and Hydrogen Oxidation," A.Z. Haddad, B.D. Garabato, P.M. Kozlowski, R.M. Buchanan, C.A. Grapperhaus, Journal of the American Chemical Society, 21Jun2016, DOI: 10.1021/jacs.6b04441



Craig A. Grapperhaus

Robert M. Buchanan

Andrew Z. Haddad

Tagsenergy, cleantech, environmental, fuels, Purification & Separation, renewable energy
Posted DateJun 23, 2016 10:12 AM


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Marketing Abstract 16082 Marketing Abstract for ULRF 16082. PDF. Download
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