Back Cover: Superior electric storage in de‐alloyed and anodic oxidized Ti–Ni–Si glassy alloy ribbons (Phys. Status Solidi RRL 7/2013)

Supercapacitor: Mikio Fukuhara et al. ( see pp. 477–480 ) discovered Ti–Ni–Si glassy alloy supercapacitors that can store electric charge on TiO 2 surfaces that contain many nanometer‐sized cavities. In contrast to the traditional electrochemical reactions, the supercapacitors do not require solutions with ions but directly charge/discharge electrons in wide temperature (∼193–453 K) and voltage (∼200 V) regions under DC and AC applications. The device consists in a distributed constant equivalent circuit of R and C . The cover picture shows de‐alloyed and anodic oxidized amorphous TiO 2 surface, where canyons of ca. 7 nm in size with higher work functions, Φ , of 5.53 eV can directly store electrons. Further gains could be attained with surface optimization.