Traditional Marcus theory accounts for electron transfer reactions in solutions, and the polarity of solvent molecule matters for them. How such an environment polarity affects electron transfer reactions in solid-state devices, however, remains uncertain. This paper describes how the Marcus inverted charge transport is influenced by solid-state molecular dilution in large-area tunneling junctions. A monolayer of 2,2′-bipyridyl terminated n-alkanethiolate (SC₁₁BIPY), which rectifies currents via electron hopping within the inverted regime, is diluted with n-alkanethiolate (SC_n) of different lengths (n = 8, 10, or 18) or at different surface mole fractions. The dilution introduces nonpolar environments within the monolayer, hinders stabilization of charged BIPY species upon electron hopping, and pushes the equilibrium of BIPY ⇄ BIPY^•– process toward the reverse direction. Our work demonstrates that solid-state molecular dilution permits systematic control of the environment polarity of active component in nanoscale devices, much like solvent polarity control in solution, and their performances.

中文翻译：

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固态稀释可控制马库斯分子在分子连接中的逆向转运

传统的Marcus理论解释了溶液中的电子转移反应，而溶剂分子的极性对它们很重要。但是，这种环境极性如何影响固态器件中的电子转移反应仍然不确定。本文描述了在大面积隧道结中，固态分子稀释如何影响Marcus反向电荷传输。2,2'-联吡啶的单层终止Ñ -alkanethiolate（SC ₁₁联吡啶），其通过整流电子倒状态内跳频的电流，用稀释Ñ -alkanethiolate（SC _Ñ不同长度的）（Ñ= 8、10或18）或不同的表面摩尔分数。稀释在单层内引入了非极性环境，阻碍了电子跳跃时带电的BIPY物种的稳定，并且将BIPY⇄BIPY ^•平衡推向反方向。我们的工作表明，固态分子稀释可以系统地控制纳米级设备中活性成分的环境极性，这与溶液中溶剂极性的控制及其性能非常相似。