Lithium‐Germanium Alloy Interfaces for Efficient Low‐Pressure Ammonia Synthesis

Abstract

ABSTRACT The lithium‐mediated nitrogen reduction reaction (Li‐NRR) offers a sustainable pathway for ammonia synthesis, providing a viable alternative to the energy‐intensive Haber‐Bosch process. While most prior studies focused on solution‐phase optimization, we introduce a transformative electrode engineering strategy via the rational design of triethylammonium germanate‐modified copper (Cu/TEG) electrodes. Multi‐technique characterization reveals the formation of the Li 15 Ge 4 alloy during the Li‐NRR. Electrochemical measurements combined with DFT calculations demonstrate that the Li 15 Ge 4 alloy simultaneously facilitates lithium deposition and shifts the N 2 adsorption energy more exothermic. Most importantly, this interfacial engineering enables a Faradaic efficiency (FE) of up to 92.5% at an unprecedented N 2 pressure as low as 4 bar and with minimal overpotential relative to the onset of lithium deposition. This synergy minimizes energy losses, achieving the highest reported pseudo‐energy efficiency value (17.6%) in a batch cell to the best of our knowledge. Overall, this work establishes dual‐function interfacial engineering via lithium‐germanium alloy formation as a breakthrough strategy, moving beyond conventional solution‐phase optimization to provide a new approach for efficient electrochemical nitrogen fixation.