Biosynthesis of triangular-shape ZnO nanoparticles using Tecoma stans and its antimicrobial activity Aayushi Biswas, a Bishwajit Changmai, a C. Vanlalveni, b R. Lalfakzuala, b Soumitra Nath, c Samuel Lalthazuala Rokhum *a,d a Department of Chemistry, National Institute of Technology Silchar, Silchar 788010, Assam, India. b Department of Botany, Mizoram University, Tanhril, Aizawl, Mizoram, 796001, India c Department of Biotechnology, Gurucharan College, Silchar 788001, Assam, India d Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK. *Corresponding authors e-mail address; rokhum@che.nits.ac.in; Tel.: +91 3842 242915; Fax: +91 3842-224797 Key words Biosynthesis; ZnO nanoparticles; Tecoma stans; Characterization; Antimicrobial activity. Highlights 1. First report on the bioinspired synthesis of triangular-shape zinc oxide nanoparticles (ZnO- NPs) using Tecoma stans. 2. XRD investigation confirmed the formation of crystalline ZnO-NPs 3. TEM images displayed the triangular shape of the synthesized NPs 4. Photoluminescence studies of NPs displays a sharp emission of blue band at 447 nm 5. The XPS spectrum revealed the presence of Zn and O in the NPs sample. 6. The synthesized ZnO-NPs showed high antimicrobial activities