Self-replicating fuels via autocatalytic molecular bond fission
This computational study introduces a theoretical framework for practical, electrochemical fuel generation displaying exponential product yields as functions of time. Exponential reaction scaling is simulated through an autocatalytic cycle that emulates the process of DNA replication facilitated by the well-known polymerase chain reaction (PCR). Here, an initial buildup of formate into a two-carbon chain through CO2 carboxylation forms oxalate. A subsequent, two-electron reduction yields glyoxylate, with base-mediated hydrolysis driving C-C bond fission of glyoxylate into two molecules of formate. These products are then recycled to serve as reactants. This recursive process chemistry drives formate evolution that scales as 2^n, where n is the cycle number. Each step of the proposed fuel cycle is analogized to the steps of DNA annealing, nucleotide polymerization and hybridized strand fission that are responsible for the exponential product yields observed in PCR-mediated DNA synthesis. As a consequence of this replication behavior, rapid rates of fuel production become accessible, even when the individual rate constants for the cycle's constituent processes are slow. Practical barriers to realizing this system are discussed, particularly the difficulty of formate carboxylation and the energy demands of chemical amplification.