Nitrogen Self-doped Activated Carbons via the Direct Activation of Samanea Saman Leaves for High Energy Density SupercapacitorsVichuda Sattayarut & Thanthamrong Wanchaem & Pundita Ukkakimapan & Visittapong Yordsri & Paweena Dulyaseree & Mayuree Phonyiem & Michiko Obata & Masatsugu Fujishige & Kenji Takeuchi & Winadda Wongwiriyapan & Morinobu EndoPDF1.0 MBEN