Formaldehyde Sensing Using Tapered U-Shape Plastic Optical Fiber Coated With Zinc Oxide Nanorods. - Siti H. Johari; Tiu Zian Cheak; Hazli Rafis Abdul Rahim; Mohd Hafiz Jali; Haziezol Helmi Mohd Yusof; Md Ashadi Md Johari; Sulaiman Wadi Harun (IEEE Access, 2022)