electrontransferdriven

Electrontransferdriven refers to processes in which the transfer of one or more electrons between chemical species is the main driving force of the reaction or transformation. In these processes, redox events couple to bond formation or cleavage, energy conversion, or signaling, so that electron movement directly determines reactivity, outcome, and selectivity.

Contexts for electron-transfer-driven phenomena span electrochemistry, photochemistry, catalysis, biology, and materials science. The two canonical mechanisms are inner-sphere electron transfer, where the electron moves through a direct bond or bridge between donor and acceptor, and outer-sphere transfer, where the electron hops through space without a bridging ligand. The rate and feasibility are described by theories such as Marcus theory, which relates the rate to the driving force (free energy change) and the system’s reorganization energy.

Key concepts commonly encountered include redox potential, donor and acceptor strengths, and proton-coupled electron transfer (PCET), in which electron transfer is coupled to proton movement. PCET is central to many biological systems and energy-conversion devices, and it provides a framework for understanding multi-proton, multi-electron processes.

Biological examples include the photosynthetic electron transport chain and cellular respiration, where sequential electron transfers create a proton gradient used to synthesize ATP. In chemistry and materials science, electron transfer drives catalytic cycles for water splitting, organic synthesis, dye-sensitized solar cells, and redox-flow batteries. In organic chemistry, radical pathways can be initiated or sustained by electron transfer from a reductant to a substrate.

Because electron transfer underpins energy conversion, sensing, and synthesis, research focuses on controlling driving force, reorganization energy, and coupling to other processes to tune rates and selectivity. The term electrontransferdriven is used as a general descriptor across disciplines to emphasize the primacy of electron exchange in observed phenomena.