Upscaling Organic Electronic Devices

Abstract

Conventional electronics based on silicon, germanium, or compounds of gallium require prohibitively expensive investments. A state-of-the-art microprocessor fabrication facility can cost up to $15 billion while using environmentally hazardous processes. In that context, the discovery of solution-processable conducting (and semiconducting) polymers stirred up expectations of ubiquitous electronics because it enables the mass-production of devices using well established high-volume printing techniques. In essence, this thesis attempts to study the characteristics and applications of thin conducting polymer films (<200 nm), and scale them up to thick-films (>100 µm). First, thin-films of organic materials were combined with an electric double layer capacitor to decrease the operating voltage of organic field effect transistors. In addition, ionic current-rectifying diodes membranes were integrated inside electrochromic displays to increase the device's bistability and obviate the need for an expensive addressing backplane.This work also shows that it is possible to forgo the substrate and produce a self-standing electrochromic device by compositing the same water-processable material with nanofibrillated cellulose (plus a whitening pigment and high-boiling point solvents). In addition, we investigated the viability of these (semi)conducting polymer nanopaper composites in a variety of applications. This material exhibited an excellent combined electronic-ionic conductivity. Moreover, the conductivities in this easy-to-process composite remained constant within a wide range of thicknesses. Initially, this (semi)conducting nanopaper composite was used to produce electrochemical transistors with a giant transconductance (>1 S). Subsequently, it was used as electrodes to construct a supercapacitor whose capacitance exceeds 1 F.

Cosexuality Reduces Pollen Production and Fitness in Cannabis sativa L.

“…Modern research has often focused on female plants [29][30][31][32][33], leaving a gap in our understanding of male plants, cosexual plants, male-male competition, and factors that impact male reproductive dynamics. Male-male competition is likely not limited to the adult life stage of male plants; the pollen grains they produce may interact with each other, representing a secondary stage of the reproductive competition and an additional opportunity for sexual selection to act [34][35][36][37][38]. The intergenerational nature of the plant life cycle could lead to differences in the direction and power of selection between paternal male plants and their haploid pollen grains [39][40][41][42], and in the case of the latter, the maintenance and expression of pollenspecific genes has implied that pollen grains are functionally independent organisms that act as vectors for male gametes [43].…”