Researchers at the Korea Institute of Civil Engineering and Building Technology (KICT) have made significant strides in tackling the challenge of poor air quality in underground road tunnels. By developing a revolutionary photocatalytic concrete, they offer a promising solution to effectively remove fine particulate matter from road environments. This cutting-edge research, aiming to combat fine particulate matter pollution, has attracted considerable attention due to its potential to enhance air quality and public health.Photocatalytic concrete harnesses the power of photocatalysts, semiconducting materials that initiate a photocatalytic reaction when exposed to light. This reaction generates reactive oxygen species (ROS) with strong oxidizing power, which can convert harmful substances, including nitrogen oxides and sulfur oxides, into harmless compounds. By integrating photocatalysts into the concrete, the researchers have developed a construction material that actively suppresses the generation of fine particulate matter.Overcoming the challenge of high manufacturing costs, the Green Construction by Photocatalyst Research Group (GCP Research Group) at KICT has been dedicated to developing cost-efficient production techniques since 2018. By focusing on wastewater sludge as a source of photocatalysts, the team has achieved both technical performance and economic competitiveness. The Ministry of Land, Infrastructure, and Transport has provided vital support for this endeavor.In a landmark trial, the GCP Research Group applied photocatalytic concrete to the inner walls of the Banpo Underground Road Tunnel in Seoul, Korea. The objective was to evaluate the effectiveness of the research findings in real-world conditions. The results were impressive, with an approximate 18% reduction in nitrogen oxides (NOx) concentration levels observed over a 24-hour period. Even in the absence of natural light, artificial light sources installed in the tunnel allowed the photocatalytic function to operate continuously. Furthermore, the by-products of photocatalytic degradation, converted into salts due to the calcium content in the concrete, were efficiently washed away by rain, ensuring the longevity of the photocatalytic effect without the need for maintenance.Beyond the trial application, the GCP Research Group is actively working on establishing certification systems to evaluate photocatalytic performance. These efforts aim to facilitate the commercialization and widespread adoption of this innovative construction technology. Collaborating with authorities in Gyeonggi-do Province, the team is conducting a comprehensive trial to demonstrate the effectiveness of photocatalytic construction technologies, setting the stage for future applications.Dr. Jong-Won Kwark, the head researcher of the project, emphasizes the immediate impact that construction technology using photocatalysts can have on improving air quality. The team plans to establish partnerships with local governments and public corporations to expand trial demonstrations to other sites, leading to practical commercialization and widespread implementation.This groundbreaking research by KICT paves the way for a future where road infrastructure actively contributes to air quality improvement. The integration of photocatalytic concrete holds immense potential for reducing fine particulate matter pollution and creating healthier living environments. As further advancements and collaborations unfold, the path to a greener and more sustainable road infrastructure becomes clearer.