The broader/commercial impact of this Small Business Innovation Research (SBIR) Phase I project is the development of accurate, fast, miniaturized and low-cost gas sensors that are suitable for integration into internet of things (IoT) devices. Successful commercial implementation of the proposed sensors would broadly benefit society. IoT devices incorporating those sensors such as smartphones and wearables can directly help 10 million asthma patients in the US and billions of air pollutant vulnerable people worldwide. These devices enhance safety by detecting dangerous conditions such as a gas leak or gas build-up in a utility, industrial plant or transportation facility. Sharing information across networks of IoT devices provides more accurate temporal and spatial gas information, promoting public safety by making the information available to emergency response and regulatory enforcement personnel. The competitive advantages of the proposed sensor over other gas sensor technologies can be transformed into commercial success by filling the market vacancy into previously inaccessible devices like smartphones. Resulting project activities would also benefit science, education and local communities by advancing the research frontier on electrochemistry and nurturing cross-disciplinary entrepreneurship with IoT applications. The proposed project brings together state-of-the-art microfabrication methods and the most recent developments of electrochemical gas sensing technology to reinvent the traditional electrochemical gas sensor. The Phase I feasibility research focuses on overcoming the unmet challenges of electrochemical gas sensor miniaturization and liquid electrolyte handling in microfabrication processes. An innovative microfabricated structure is proposed using semiconductor-compatible manufacturing processes. Sensor stability is proposed to be studied in the context of the electrode-electrolyte interface, a not well understood area. The proposed microfabricated structures bring a new quantitative perspective to the electrode-electrolyte interface study and may generate new knowledge on fundamentals to help improve sensor performance. The proposed research activity is expected to achieve a carbon monoxide sensor of 2x2x0.5mm form factor that consumes sub micro amps of current, demonstrated by an IoT sensor network platform. In Phase II, sensors of more gases, including ozone, nitric oxide, methane, etc. will be implemented on a complementary metal oxide semiconductor (CMOS) integrated circuit (IC) containing potentiostats and a data converter through post-CMOS microfabrication processes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.