Pre-Anchored NiFe2O4 Quantum Dots Enable Alkali-Regulated MOF-Derived NiCo-LDH Heterostructures for Enhanced Supercapacitor Performance

Pre-anchoring and alkali-regulated strategy constructs NiCo-LDH@NiFe 2 O 4 QDs heterostructure. • NiFe 2 O 4 quantum dots boost conductivity and structural stability of LDH. • Alkali source tuning modulates nanosheet morphology and ion diffusion. • The NiCo-LDH@QDs-K electrode delivers 2195.55   F·g -1 at 1   A·g -1 . • Asymmetric supercapacitor achieves 80.98   Wh·kg -1 , powers timer for 28   min. Layered double hydroxides (LDHs) derived from metal-organic frameworks (MOFs) possess high theoretical capacitance. However, their inherent low conductivity and structural instability during cycling limit practical applications. In this study, we propose an innovative pre-anchoring and directed conversion synthesis strategy for the rational synthesis of a tightly integrated NiCo-LDH with quantum dots (QDs) composite. Highly conductive NiFe 2 O 4 QDs were uniformly pre-anchored onto the surface of NiCo-BTC, followed by precise regulation of the alkalization process to in situ convert the precursor into LDH. Owing to the spatial confinement effect of the MOF precursor, aggregation of the quantum dots is effectively suppressed. Meanwhile, the in situ conversion process establishes strong interfacial coupling and efficient ion/electron transport pathways between the two components, thereby synergistically improving electrical conductivity, charge-transfer kinetics, and structural robustness.Benefiting from this unique structural design, the resulting composite exhibited outstanding electrochemical performance, achieving a specific capacitance of 987.99   C·g -1 at a current density of 1   A·g -1 . Furthermore, an asymmetric supercapacitor assembled with this composite as the positive electrode achieved an energy density of 80.98   Wh·kg -1 at a power density of 784.94   W·kg -1 and is capable of powering commercial electronic devices. This study provides an effective strategy for developing high-performance MOF-derived electrode materials through interfacial structural design. Download: Download high-res image (226KB) Download: Download full-size image Through pre-anchoring and targeted conversion strategies, NiFe 2 O 4 quantum dots were uniformly anchored onto the NiCo-BTC surface and in situ converted into LDH, successfully constructing the NiCo-LDH@NiFe 2 O 4 QDs composite material. The asymmetric supercapacitors assembled from this material exhibited high energy density.