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Terahertz (THz) technologies provide opportunities ranging from calibration targets for satellites and telescopes to communication devices and biomedical imaging systems. A main component will be broadband THz absorbers with switchability. However, optically switchable materials in THz are scarce and their modulation is mostly available at narrow bandwidths. Realizing materials with large and broadband modulation in absorption or transmission forms a critical challenge. This study demonstrates that conducting polymer-cellulose aerogels can provide modulation of broadband THz light with large modulation range from approximate to 13% to 91% absolute transmission, while maintaining specular reflection loss < -30 dB. The exceptional THz modulation is associated with the anomalous optical conductivity peak of conducting polymers, which enhances the absorption in its oxidized state. The study also demonstrates the possibility to reduce the surface hydrophilicity by simple chemical modifications, and shows that broadband absorption of the aerogels at optical frequencies enables de-frosting by solar-induced heating. These low-cost, aqueous solution-processable, sustainable, and bio-friendly aerogels may find use in next-generation intelligent THz devices., Funding Agencies|Swedish Research Council(VR); Swedish Foundation for Strategic Research (SSF); Stellenbosch Institute for Advanced Study (STIAS); Swedish Foundation for International Cooperation in Research and Higher Education (STINT); Knut and Alice Wallenberg Foundation; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkping University [61831012]; National Natural Science Foundation of China (NFSC) [62131006, 52003202, 2023YFB381130005, 2021JDTD0026, 2023JDGD0012]; National Key Research and Development Program of China [2019-252]; Sichuan Province Science and Technology Support Program [2020-00287, 2022-00211]; Guangdong Science and Technology Major Special Fund [2022-06214]; Wallenberg Wood Science Center; [2009 00971]; [62311530115]; [62235004]

Biomimicry at the hardware level is expected to overcome at least some of the challenges, including high power consumption, large footprint, two-dimensionality, and limited functionality, which arise as the field of artificial intelligence matures. One of the main attributes that allow biological systems to thrive is the successful interpretation of and response to environmental signals. Taking inspiration from these systems, the first demonstration of using multiple environmental inputs to trigger the formation and control the growth of an evolvable synaptic transistor is reported here. The resulting transistor exhibits long-term changes in the channel conductance at a fixed gate voltage. Biomimetic logic circuits are investigated based on this evolvable transistor that implement temperature and pressure inputs to achieve higher order processes like self-regulation of synaptic strength and coincidence detection., Funding Agencies|Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research [SE13-0045, RMX18-0083]; Swedish Research CouncilSwedish Research CouncilEuropean Commission [2016-03979, 2018-06197]; AForsk [18-313, 19-310]; Olle Engkvists Stiftelse [204-0256]; European Research CouncilEuropean Research Council (ERC)European Commission [834677]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]

Poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) (PEDOT:PSS) has been reported as a successful functional material in a broad variety of applications. One of the most important advantages of PEDOT:PSS is its water-solubility, which enables simple and environmental friendly manufacturing processes. Unfortunately, this also implies that pristine PEDOT:PSS films are unsuitable for applications in aqueous environments. To reach stability in polar solvents, (3-glycidyloxypropyl)trimethoxysilane (GOPS) is typically used to cross-link PEDOT:PSS. Although this strategy is widely used, its mechanism and effect on PEDOT:PSS performance have not been articulated yet. Here, we present a broad study that provides a better understanding of the effect of GOPS on the electrical and electronic properties of PEDOT:PSS. We show that the GOPS reacts with the sulfonic acid group of the excess PSS, causing a change in the PEDOT:PSS film morphology, while the oxidation level of PEDOT remains unaffected. This is at the origin of the observed conductivity changes. (c) 2017 Wiley Periodicals, Inc.