This study involves the synthesis of indium nitride (InN) nanoparticles at low temperature using a chemical method. The synthesized InN nanoparticle exhibited high quality crystalline cubic phases with In2O3 impurity. The average diameter of the cubic phases ranges from 11.4 nm to 21.4 nm. The energy gap of the synthesized InN nanoparticle is approximately 0.97 eV. Under illuminasion (30 mW/cm(2)) the n-InN/p-Si (1 1 1) hetro-junction solar cells displayed a short circuit current of 1.2 mA and power-conversion efficiency of 1.09%. This work demonstrates the first successful synthesis of n-type InN nanoparticles at low temperature using a chemical method. This novel approach is an important breakthrough in the development of InGaN-based full-solar-spectrum photovoltaic. (C) 2013 Elsevier Ltd. All rights reserved.