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With rapid advance of wearable electronics technologies, flexible strain sensors having both high sensitivity and high stretchability are highly desired. In this work, inspired by lotus roots whose fibers remain joined even after fracture, highly sensitive and stretchable strain sensors are designed using single-walled carbon nanotube (SWNT)/graphene oxide (GO) hybrid thin films with unique wrinkled, cracked and bridged morphologies. The distinctive wrinkled and cracked structure is created by tuning the pre-stretching releasing of the hybrid film on a silicone rubber substrate. Under tension, the myriad SWNTs bridged the wrinkled film by sliding within the hybrid film giving rise to high stretchability, while the nano/microscale cracks provide the strain sensor with a high sensitivity through tunneling. Thanks to the synergy arising from the wrinkles, cracks and bundles bridged the cracks, the hybrid sensor exhibits a wide sensing range of 100 %, an ultrahigh gauge factor of 2000 with excellent stability for over 1000 cycles. These exceptional properties enable the sensor to monitor full range human motions from tiny eye blinks to large joint movements. A wearable gaming controller is prototyped using the developed sensor to demonstrate voice-empowered maneuver of car racing games.

trans-Diethynylethene [(E)-hex-3-ene-1,5-diyne (1a)], geminal-diethynylethene [3-ethynyl-but-3-ene-1-yne (1b)], and tetraethynylethene [3,4-diethynyl-hex-3-ene-1,5-diyne (2)] are flexible molecular building blocks for pi-conjugated polymers with interesting electronic and photonic properties. The type of functionalization, the length of the polymer chain, and the choice of pi-conjugation pattern, play a crucial role in determining the properties of these compounds. To rationalize the impact of the different delocalization pathways in the various types of isomers (trans or geminal) on the molecular and electronic structure, a detailed theoretical investigation is presented. We develop a method based on the natural bond orbital (NBO) analysis of Weinhold, which allows one to correlate electron delocalization with molecular and electronic structure observables. The method reveals that the difference between trans (or through) and geminal (or cross) conjugation is not only due to the vertical pi conjugation, but also to the in-plane sigma hyperconjugation. The method is used to correlate the changes in molecular and electronic observables, such as the bond lengths or the absorption frequencies, with the electronic structure of the compounds under investigation. Moreover, this method allows us to predict how a certain substituent will affect the molecular structure and the electronic properties of a given backbone.