Energy storage is increasingly recognized as a key technology to enable our ongoing transition to a sustainable energy model. Electrochemical energy storage will be key to this transition but is still far from optimal. That is why there is still plenty of room for new and novel types of materials for batteries and for supercapacitors. Hybrid materials offer opportunities for synergy and new properties with respect to their components.[1] Those formed by electroactive and conducting components are of particular interest for energy storage applications.[2, 3, 10]

We have developed a whole line of work dealing with hybrid electroactive (oxides[9], phosphates[4] polioxometalates[5-8]) and conductive materials (conducting polymers or carbons) for energy storage applications.[4-9] In this conference we will address the different approaches towards hybridizing energy storage by taking the hybridization concept to a chemical level and will discuss the several multifunctional synergies hybrids provide. In particular, in addition to conductive-electroactive combinations, we will show how hybrids can be designed to take advantage of dual energy storage mechanisms by combining the typical capacitive behavior of supercapacitors with the characteristic faradaic activities of batteries, thus, blurring the borderlines between these two types of devices.[10]

[1] P. Gomez-Romero Adv.Mater. 2001, 13(3), 163.

[2] P. Gomez-Romero et al. J.Solid State Electrochem. 2010 14(11), 1939

[3] Ait Salah et al. J.Electrochem.Soc. 2006, 153(9), A1692.

[4] A. Fedorkova et al. Electrochim.Acta 2010, 55(3), 943

[5] J. Vaillant et al. Progress in Solid State Chemistry, 2006, 34, 147.

[6] V. Ruiz, J. Suárez-Guevara, P. Gomez-Romero Electrochem. Communications 2012, 24, 35.

[7] J. Suarez-Guevara, V. Ruiz and P. Gomez-Romero J.Mat.Chem.A, 2014, 2, 1014.

[8] D P Dubal, et al. Journal of Materials Chemistry A 2015, 3(46), 23483

[9] D P. Dubal, R. Holze, P. Gomez-Romero. Scientific Reports 2014, 4 : 7349

[10] D.P. Dubal, V. Ruiz, O. Ayyad and P. Gomez-Romero Chem.Soc.Rev. 2015 44(7):1777-90