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Graphical abstract Highlights • MOF-derived α-Fe 2 O 3 microboxes modified by Ag nanoclusters were fabricated. • Porous and hollow Fe 2 O 3 microboxes provide high surface area and rich active sites. • Ag nanoclusters improve the conductivity and enhance the structural stability. • α-Fe 2 O 3 @Ag microboxes are a promising anode material for supercapacitors. Abstract Porous hollow α-Fe 2 O 3 microboxes with high surface area are prepared by using metal-organic framework as precursor and self-template. To improve the conductivity of the derived α-Fe 2 O 3 microboxes and thus enhance their capacitive storage and rate capability as effective electrode material, especially as anode material for supercapacitors, Ag nanoclusters are uniformly deposited on the surface of the α-Fe 2 O 3 microboxes (α-Fe 2 O 3 @Ag microboxes) through a facile solution method. As pseudocapacitive material, the α-Fe 2 O 3 @Ag microbox electrode displays a high specific capacitance of 701 F g−1 at a current density of 0.1 A g−1, and remains 191 F g−1 at a high current density of 10 A g−1. Furthermore, the material shows 80% specific capacitance retention after 2000 charge-discharge cycles, and 72% retention after 10,000 cycles at a current density of 10 A g−1. In addition, asymmetric supercapacitors are assembled with the α-Fe 2 O 3 @Ag as negative electrodes and commercial activated carbon as positive electrodes. A maximum specific capacitance of 123 F g−1 and an energy density of 41.8 W h kg−1 are demonstrated within a cell voltage of 1.6 V for the device. [ABSTRACT FROM AUTHOR]