Exploring Eco-Sustainability in Functionally Unconventional Magnetic Field Sensors.

Magnetic field sensors are indispensable components in modern electronics owing to their reliable, contactless operation. Over the last decades, the rapid advancement of emerging technologies (e.g., wearable devices, transparent electronics, virtual and augmented reality, soft robotics, and the Internet of Things) has not only fueled the expanding demand for magnetic field sensors but also imposed increasingly stringent requirements on their performance and functionality. However, conventional fabrication processes, predominantly based on thin-film techniques, often entail energy-intensive procedures and excessive material waste, generating significant environmental impacts. Furthermore, the intrinsic rigidity and opacity of traditional sensors hinder their seamless integration into next-generation platforms. In response, the research community has undertaken extensive efforts to reconcile unconventional functionality with environmental sustainability. This review highlights recent advances in this direction, focusing on strategies that endow magnetic field sensors with mechanical flexibility and optical transparency while simultaneously addressing sustainability challenges throughout their entire life cycle.