کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1298682 974015 2008 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Nano-structural tailoring of manganese dioxide by using pulse current electrodeposition
موضوعات مرتبط
مهندسی و علوم پایه شیمی الکتروشیمی
پیش نمایش صفحه اول مقاله
Nano-structural tailoring of manganese dioxide by using pulse current electrodeposition
چکیده انگلیسی

A pulse current technique has been applied for the preparation of Manganese Dioxides (PCMD) in an additive-free MnSO4–H2SO4 solution. The influence of pulse current parameters on surface characteristics has been studied by using scanning electron microscopy (SEM). Pore size distribution (PSD) of samples is determined from the desorption isotherm according to the Barrett–Joyner–Halenda (BJH) model. The subsequent effects on charge\discharge cycle performance of deposited materials have been studied in laboratory designed RAM batteries. SEM images confirmed a decrease in PCMDs surface roughness showing more coherent and cracks-free deposits compares to a sample, which is deposited by direct current (DCMD). Results show that under optimized pulse condition, PSD data in PCMD is narrower and less than 3 nm, whereas DCMD exhibits a boarder pore size distribution and larger pore volume. Grain size, pore size distribution and pore volume were established to be important factors determining electrochemical behavior of deposited materials. Results of RAM batteries revealed that the cycle life of batteries made of PCMDs were rather higher than that made by conventional DCMD. Functional improvements are mainly attributed to enhanced current distribution as well as fewer amounts of incorporated water molecules into the PCMD crystal lattice. These could be considered as a result of lower accumulation of passive intermediates and a lower anodic overvoltage during electrodeposition of PCMD. Depending on the applied pulse parameters, nano-tailoring of PCMDs in different morphological varieties is possible.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Solid State Ionics - Volume 179, Issue 39, 15 December 2008, Pages 2278–2283
نویسندگان
, ,