Engineering “JiaoJiao” (maltose syrup) with chopsticks: From traditional Chinese sweet food to skin-like iontronics

The advancement of technology has had a profound impact on all areas of life, with an ever more intimate integration of the digital and biological spheres, but it may also be accompanied by an environmental crisis caused by the abuse of large quantities of electronics and petrochemicals. Next-generation “green” electronics or iontronics with high biocompatibility, biodegradation, low cost and mechanical compliance promise to mitigate these adverse effects, but are often limited by the finite choices of materials and strategies. Herein, maltose syrup, a traditional water-dissolvable saccharide food called “JiaoJiao” in Chinese, is engineered to replace unsustainable conductive components of current electronic devices. After churning and pulling with two chopsticks, known as aeration, the aerated maltose syrup has optimized viscoelasticity, mechanical adaptation, robustness, remodeling and self-healing capability, yet with transient behavior. Moreover, the structural and viscoelastic evolution during aeration is also analyzed to maximize the contribution from structures. As a proof-of-concept, a type of “green” skinlike iontronics is prepared, which exhibits reliable strain sensing ability and is subsequently applied for intelligent information encryption and transmission based on a novel concept of sending Morse code. This work greatly extends the current material choice and is expected to shed light on the development of a sustainable future.