Engineering lateral and vertical heterostructures for supercapacitors with unprecedented energy density

Constructing lateral and vertical heterostructures with quantum-scale opens up a new stage for engineering materials duo to their adjustable electronic structure and enhanced reaction kinetics. Herein, the V2O3 embedded VPO4-nanocarbon heterostructures (V2O3@VPO4-NC) with hollow cubic morphology are prepared via one-step in-situ growth, which is the first to report the confined vanadium-base lateral and vertical heterostructures. Adhering to the concept of lateral and vertical growth, the charge redistribution at the heterogeneous phase boundaries is authenticated by density functional theory (DFT) calculations. Examined as the supercapacitor electrode, the V2O3@VPO4-NC manifests superior electrochemical properties in terms of an ultrahigh specific capacitance of 2797.3F g−1 at 1 A g−1 and 1510.5F g−1 at 10 A g−1, as well as an ultralong cycle life over 10,000 cycles. In parallel, an all-solid-state interdigital micro-supercapacitors with water-in-LiCl electrolyte achieves a record operating voltage of 1.8 V, delivering a dual-boosted volumetric/areal energy density of 4637.6 Wh/L and 97.7 mWh cm−2, which could bear comparison with the best lithium primary batteries, aqueous microbatteries and hybrid supercapacitors. This work underpins the importance of lateral and vertical heterostructures for future miniaturized and integrated electronics.