@article{sakorikar_mihaliak_krisnadi_ma_kim_kong_awartani_dickey_2024, title={A Guide to Printed Stretchable Conductors}, volume={1}, ISSN={["1520-6890"]}, url={https://doi.org/10.1021/acs.chemrev.3c00569}, DOI={10.1021/acs.chemrev.3c00569}, abstractNote={Printing of stretchable conductors enables the fabrication and rapid prototyping of stretchable electronic devices. For such applications, there are often specific process and material requirements such as print resolution, maximum strain, and electrical/ionic conductivity. This review highlights common printing methods and compatible inks that produce stretchable conductors. The review compares the capabilities, benefits, and limitations of each approach to help guide the selection of a suitable process and ink for an intended application. We also discuss methods to design and fabricate ink composites with the desired material properties (e.g., electrical conductance, viscosity, printability). This guide should help inform ongoing and future efforts to create soft, stretchable electronic devices for wearables, soft robots, e-skins, and sensors.}, journal={CHEMICAL REVIEWS}, author={Sakorikar, Tushar and Mihaliak, Nikolas and Krisnadi, Febby and Ma, Jinwoo and Kim, Tae-il and Kong, Minsik and Awartani, Omar and Dickey, Michael D.}, year={2024}, month={Jan} }
 @article{rahmani_shojaei_sakorikar_wang_mendoza-apodaca_dickey_2024, title={Liquid Metal Nanoparticles Physically Hybridized with Cellulose Nanocrystals Initiate and Toughen Hydrogels with Piezoionic Properties}, volume={3}, ISSN={["1936-086X"]}, url={https://doi.org/10.1021/acsnano.3c11063}, DOI={10.1021/acsnano.3c11063}, abstractNote={Liquid metal (LM) particles can serve as initiators, functional fillers, and cross-linkers for hydrogels. Herein, we show that cellulose nanocrystals (CNCs) stabilize LM particles in aqueous solutions, such as those used to produce hydrogels. The CNC-coated LM particles initiate free-radical polymerization to form poly(acrylic acid) (PAA) hydrogel with exceptional properties─stretchability ∼2000%, excellent toughness ∼1.8 MJ/m3, mechanical resilience, and efficient self-healing─relative to cross-linked PAA networks polymerized using conventional molecular initiators. FTIR spectroscopy, rheology, and mechanical measurements suggest that physical bonds between PAA and both Ga3+ and LM-CNC particles contribute to the excellent mechanical properties. The gels are used to sense a wide range of strains, such as those associated with human motion, via changes in resistance through the gel. The sensitivity at low strains enables monitoring subtle physiological signals, such as pulse. Without significantly compromising the toughness, soaking the gels in salt solution brings about high ionic conductivity (3.8 S/m), enabling them to detect touch via piezoionic principles; the anions in the gel have higher mobility than cations, resulting in significant charge separation (current ∼30 μA, ∼10 μA/cm2) through the gel in response to touch. These attractive properties are promising for wearable sensors, energy harvesters, and self-powered ionic touch panels.}, journal={ACS NANO}, author={Rahmani, Pooria and Shojaei, Akbar and Sakorikar, Tushar and Wang, Meixiang and Mendoza-Apodaca, Yuniva and Dickey, Michael D.}, year={2024}, month={Mar} }