This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/ep.13492 An experimental investigation on performance, combustion and emission characteristics of diesel doped with green synthesized nano cerium oxide R. Magudieshwaran 1* , R. Venkatachalam 2 , P. Senthilkumar 3 , S. Magibalan 3, M. Kathirselvam 4 1 Department of Industrial Safety Engineering, K.S.Rangasamy College of Technology, Tiruchengode - 637 215, Namakkal, Tamil Nadu, India. 2 Department of Automobile Engineering, Institute of Road and Transport Technology, Erode - 638 316, Tamil Nadu. India. 3 Department of Mechanical Engineering, K.S.R.College of Engineering, Tiruchengode - 637 215, Namakkal, Tamil Nadu, India 4 Department of Mechanical Engineering, K.S.Rangasamy College of Technology, Tiruchengode - 637 215, Namakkal, Tamil Nadu, India. 1* E-mail: magudieshwaran123@yahoo.com Abstract This study reports the potential of Cerium oxide (CeO2) nanoparticles synthesized from Jatropha curcus leaves and Insulin plant extracts to use as a doping constituent with diesel fuel. Investigations were carried out to analyze the effect of cerium oxide nanoparticles on engine performance and smoke emission characteristics. X-ray diffraction study witness the presence of Cerium oxide in the plant extracts and the average crystal size of CeO2 nanoparticles synthesized from Jatropha curcus leaves and Insulin plant extracts was 5 nm and 25 nm respectively. Experimental runs were carried out on a 4 Stroke Direct Injection VCR diesel engines at two different compression ratios. The result This article is protected by copyright. All rights reserved.