In the last 12 months ... The research community has made great progress toward solving the "selectivity challenge" in electrochemical ammonia synthesis. Although, rather than an actual solution, mostly what we have is a range of sophisticated work-arounds that succeed in making this problem moot.
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Sustainable ammonia synthesis: SUNCAT's lithium-cycling strategy
New research coming out of Stanford University suggests a fascinating new direction for electrochemical ammonia synthesis technology development. The US-Danish team of scientists at SUNCAT, tasked with finding new catalysts for electrochemical ammonia production, saw that 'selectivity' posed a tremendous challenge - in other words, most of the energy used by renewable ammonia production systems went into making hydrogen instead of making ammonia. The new SUNCAT solution does not overcome this selectivity challenge. It doesn't even try. Instead, these researchers have avoided the problem completely.