Electrochemically Active In Situ Crystalline Lithium-Organic Thin Films by ALD/MLD

Intercalated metal-organic framework (iMOF) type electrochemically active aromatic metal carboxylates are intriguing material candidates for various energy storage devices and microelectronics. In this work, we grow in situ crystalline thin films of such materials through atomic/molecular layer deposition (ALD/MLD); the remarkable benefit of this approach is the possibility to evaluate their electrochemical properties in a simple cell configuration without any additives. Five organic linkers are investigated in combination with lithium: terephthalic acid (TPA), 3,5-pyridinedicarboxylic acid (PDC), 2,6-naphthalenedicarboxylic acid (NDC), 4,4'-biphenyldicarboxylic acid (BPDC), and 4,4'-azobenzenedicarboxylic acid (AZO). In particular, the electrochemical activity of Li-PDC and the crystal structure of Li-AZO are addressed here for the first time. We believe that the in situ gas-phase thin-film deposition is a crucial requirement to benefit from the iMOF-type electrode materials in, e.g., microelectronics and wearable devices.