Organic semiconductors have enough molecular versatility to feature chemo-specific electrical sensitivity to large families of chemical substituents via different intermolecular bonding modes. This study demonstrates that one single conducting polymer can be tuned to either discriminate water-, ethanol- or acetone-vapors, on demand, by changing the nature of its dopant. Seven triflate salts differ from mild to strong p-dopant on poly(3-hexylthiophene) sensing micro-arrays. Each material shows a pattern of conductance modulation for the polymer which is reversible, reproducible, and distinctive of other gas exposures. Based on principal component analysis, an array doped with only two different triflates can be trained to reliably discriminate gases, which re-motivates using conducting polymers as a class of materials for integrated electronic noses. More importantly, this method points out the existence of tripartite donor-acceptor charge-transfer complexes responsible for chemospecific molecular sensing. By showing that molecular acceptors can have duality to p-dope semiconductors and to coordinate donor gases, such behavior can be used to understand the role of frontier orbital overlapping in organic semiconductors, the formation of charge-transfer complexes via Lewis acid-base adducts in molecular semiconductors.

有机半导体具有足够的分子多功能性，可以通过不同的分子间键合模式对大家族的化学取代基具有化学特异性的电敏感性。这项研究表明，通过改变掺杂剂的性质，可以调整一种单一的导电聚合物，以根据需要区分水、乙醇或丙酮蒸汽。七种三氟甲磺酸盐在聚（3-己基噻吩）传感微阵列上从轻度到强的 p 掺杂剂不同。每种材料都显示出聚合物的电导调制模式，该模式是可逆的、可重复的，并且与其他气体暴露不同。基于主成分分析，可以训练只掺杂两种不同三氟甲磺酸酯的阵列来可靠地区分气体，这再次激发了使用导电聚合物作为集成电子鼻的一类材料的动机。更重要的是，该方法指出了负责化学特异性分子传感的三方供体-受体电荷转移复合物的存在。通过表明分子受体对 p 掺杂半导体和配位气体具有二重性，这种行为可用于理解前沿轨道重叠在有机半导体中的作用，通过路易斯酸碱加合物形成电荷转移复合物分子半导体。