Advances in gas sensors using screen printing

Gas sensing is crucial for detecting and monitoring hazardous, gases in various environments to ensure safety and prevent potential health risks. It helps in the early identification of gas leaks, air quality monitoring, and environmental protection, contributing to public health and industrial safety. Screen-printed gas sensors are trending nowadays due to their ability to fabricate electrodes or deposit functional components onto substrates and their cost-effective and scalable manufacturing process, making them suitable for mass production. This review provides an overview of screen printing and hybrid screen printing techniques utilizing different methods, such as spin coating, drop casting, spray coating, and inkjet printing (IJP), with screen printing for various gas sensing applications. The mechanism of each hazardous gas detection technique, their precision in the identification of hazardous gases, and their impact on sensor enhancement were thoroughly analyzed. Furthermore, the vital integration of screen-printed gas sensors with various futuristic technologies, such as artificial intelligence (AI), machine learning (ML), and Internet of Things (IoT) devices, supercapacitors (SCs), triboelectric nanogenerators (TENGs), and microheaters, was demonstrated to enhance sensor performance and broaden the application area. Moreover, this review highlighted the importance of sensors' sensitivity, selectivity, and environmental stability, which offer plenty of room for innovation. For future improvements, the integration of microfluidic, multi-sensor arrays, functional coatings, and nanomaterials into screen-printed gas sensor devices was proposed. In this context, gas sensing platforms can be refined by operating them using energy harvesting principles, improving their environmental stability, and making them wearable and flexible. This review paper would benefit many researchers and readers working in this field to familiarize themselves with the recent breakthroughs in the rapidly emerging field of screen-printed gas sensing.