High-performance supercapacitors of carboxylate-modified hollow carbon nanospheres coated on flexible carbon fibre paper: Effects of oxygen-containing group contents, electrolytes and operating temperature - Phattharasupakun, N; Wutthiprom, J; Suktha, P; Iamprasertkun, P; Chanlek, N; Shepherd, C; Hadzifejzovic, E; Moloney, M; Foord, J; Sawangphruk, M (Electrochimica Acta, 2017)