Emerging materials and technologies for next-generation sensors in smart IoT systems: a comprehensive review

As the Internet of Things (IoT) continues to advance at an unprecedented rate, there is a growing need for intelligent, adaptable, low-power and sustainable sensing platforms that can operate autonomously over long periods. This paper examines the technological advances in IoT sensing systems, specifically focusing on the utilization of nanomaterials, 2D materials, conductive polymers and hybrid composites (including composites with other materials) to improve sensitivity, flexibility and device size. Other next-generation methods of designing these devices include the integration of artificial intelligence (AI) into sensors; creating stretchy and/or wearable sensor systems; and developing energy harvesting technology to provide continuous power to the devices. Each of these types of sensing systems has distinct design features and advantages, which are described in the body of it, along with relevant research that has been conducted on them. Finally, key challenges confronting researchers and practitioners will be discussed, such as; the durability and power stability of their designs, the development of Edge-AI optimization methods, and the availability of mass production techniques for their designs. The findings of this can help scaffold future researchers and practitioners in the development of intelligent sensing solutions which are environmentally friendly, battery free, and fully self-learning for the IoT sensor networks of the future.