1. SONOCHEMICAL SYNTHESIS OF NANO MANGANESE DIOXIDE PARTICLES FOR BATTERY APPLICATIONS K. Saminathan, S. R. Srither, K. KathiKeyan, S. Praveen and V. Rajendran Centre for Nano science and Technology, K.S.Rangasamy College of Technology Tiruchengode-637215, Tamil Nadu, India The present study is aimed to develop MnO 2 nanoparticles using sonochemical synthesis. MnO 2 is widely used in dry cell as a cathode material. Sonochemical method is practically inexpensive, and is very simple technique to produce nano sized particles. During the sonochemical process, very high temperature is generated in the liquid medium due to the rapid collapse of soni9+9cally generated cavities which allows the conversion of manganese salts into manganese dioxide nanoparticles. Capping agents such as poly ethylene glycol (PEG) and ploy vinyl alcohol (PVA) are used to control the growth of particle size. SEM-EDAX, TEM and XRD studies are used to characterize the manganese dioxide nanoparticles. Discharge characteristics such as self discharge, closed circuit voltage (CCV), energy density, power density and capacity of the test cells are performed. The above results reveal that the synthesized nanosized MnO 2 particles show 30% improved capacity than bulk MnO 2. Abstract Objectives Synthesis of Nano γ-MnO 2 by sonochemical method Unique properties - Electro chemically active, low density, good strength at elevated temperatures Advantages - low-cost, simple process and an amorphous MnO 2 has excellent electrochemical behavior Applications - component of dry cell batteries, Lithium Ion Batteries, Super capacitors Experimental Procedure Manganese acetate + D.D. Water in a beaker Ammonium Hydroxide KMnO 4 Add Drop-wise under Sonication with Ice-bath Brown Colloid Amorphous MnO 2 nanoparticles Structural Analysis - FTIR The band at 515 cm - 1 is ascribed to the Mn-O vibrations of MnO 2 NPs 617 cm - 1 is the Mn-O stretching modes of tetrahedral A- and octahedral B- sites 632 cm - 1 is attributed to Contribution of O-H bending vibration combined with Mn atoms XRD - Analysis XRD patterns of γ-MnO 2 heat treated at 200°C correspond to amorphous γ-MnO 2 SEM SEM image shows that the particles are interconnected to each other to form an agglomeration The average size of the particle is 72nm TEM MnO 2 is not closely constrained in the arrangement of many small particles Electron diffraction pattern is in the form of toroid with few apparent rings confirms amorphous with little crystalline grains Mn - 55.71%, O - 35.71 %, K - 8.58% Purity of MnO 2 is 91.42 % EDAX - Spectra Particle size reveals that the particles are uniformly oriented Particle size distribution is in the range of 42-150 nm Maximum distribution (d50) of particles is 85±3nm Particle Size Distribution Conclusion The present investigation deals with the production of amorphous MnO 2 nanoparticles were synthesized by sonochemical method. FTIR results shows that the commercial MnO 2 peaks are similar with the synthesized MnO 2 peaks. The amorphous structure was determined by TEM and XRD analysis. Particle size distribution shows maximum number of 87 nm MnO 2 particles are formed in the sonochemical synthesis. Improved capacity in the Discharge studies confirm the MnO 2 Electrochemical activity is 30% improved Chemical Reaction Light discharge : Zn + 2MnO 2 + 2NH 4 Cl → 2MnOOH + Zn(NH 3 ) 2 Cl 2 Heavy discharge : Zn + 2MnO 2 + NH 4 Cl + H 2 O → 2MnOOH + NH 3 + Zn(OH)Cl Prolonged discharge : Zn + 6MnOOH → 2Mn 3 O 4 + ZnO + 3H 2 O CENTER FOR NANOSCIENCE & TECHNOLOGY K.S.RANGASAMY COLLEGE OF TECHNOLOGY CENTER FOR NANOSCIENCE & TECHNOLOGY K.S.RANGASAMY COLLEGE OF TECHNOLOGY Future Work Lithium Ion battery development Super Capacitor applications Discharge Studies