The use of broadband light energy is important for enhancing photoenergy conversion. However, bifunctional materials that can efficiently harvest solar energy to assist electrochemical energy storage are difficult to prepare. Herein, copper foam (CF)-supported cuprous sulfide (Cu 2 S) heteroarrays (CS HAs) with enriched sulfur (S) vacancies (V S ) were designed for photo-rechargeable pseudocapacitors. A direct hydrothermal sulfurization of CF first resulted in the growth of CS HAs with leaf-like heterostructures. Subsequent partial oxidation of S 2− in FeCl 3 aqueous solution enriched the V S within the leaf-like structures. In addition, CuCl and Cu 2 O were formed from Cu 2 S during FeCl 3 treatment to derive a bifunctional photoelectrode with ternary components, thus further broadening the light absorption region. Thus, the optimal CS HAs have demonstrated areal capacitances of 1440-1048 mF cm −2 with the assistance of the photoelectric/ thermal effects of light energy, delivering remarkable photoenhancements of 25%-35%. The asymmetrical pseudocapacitors fabricated from the optimal photoelectrodes delivered a high areal capacitance of 670 mF cm −2 after 6000 cycles, suggesting a promising application in transparent light-driven energy devices.

To meet the increasing demands of energy consumption, sustainable energy sources such as solar energy should be better employed to promote electrochemical energy storage. Herein, we fabricated a bifunctional photoelectrode composed of copper foam (CF)-supported zinc-nickel-copper ternary oxides in nanoarrays (CF@ZnCuNiOx NAs) to promote photo-enhanced pseudocapacitive charge storage. The as-fabricated CF@ZnCuNiOx NAs have shown both photosensitive and pseudocapacitive characteristics, demonstrating a synergistic effect on efficient solar energy harvest and conversion. As a result, a high areal specific capacitance of 2741 mF cm−2 (namely 418 μAh cm−2) under light illumination can be calculated at 5 mA cm−2, which delivered photo-enhancement of 38.3% compared to that obtained without light. In addition, the photoelectric and photothermal effects of the light energy on pseudocapacitive charge storage have been preliminarily studied and compared. This work may provide some evidence on the different mechanisms of photoelectric/thermal conversion for developing solar-driven energy storage devices.