Direct Utilization of Photoinduced Charge Carriers to Promote Electrochemical Energy Storage

Abstract

Electrochemical energy storage has been regarded as one of the most promising strategies for next‐generation energy consumption. To meet the increasing demands of urban electric vehicles, development of green and efficient charging technologies by exploitation of solar energy should be considered for outdoor charging in the future. Herein, a light‐sensitive material (copper foam‐supported copper oxide/nickel copper oxides nanosheets arrays, namely CF@CuOx@NiCuOx NAs) with hierarchical nanostructures to promote electrochemical charge storage is specifically fabricated. The as‐fabricated NAs have demonstrated a high areal specific capacity of 1.452 C cm−2 under light irradiation with a light power of 1.76 W, which is 44.8% higher than the capacity obtained without light. Such areal specific capacity (1.452 C cm−2) is much higher than that of the conventional supercapacitor structure using a similar active redox component reported recently (NiO nanosheets array@Co3O4‐NiO FTNs: maximum areal capacity of 623.5 mF cm−2 at 2 mA cm−2). This photo‐enhancement for charge storage can be attributed to the combination of photo‐sensitive Cu2O and pseudo‐active NiO components. Hence, this work may provide new possibilities for direct utilization of sustainable solar energy to realize enhanced capability for energy storage devices.

Photoirradiation-Induced Capacitance Enhancement in the h-WO3/Bi2WO6 Submicron Rod Heterostructure under Simulated Solar Illumination and Its Postillumination Capacitance Enhancement Retainment from a Photocatalytic Memory Effect

“…However, solar energy has a low density and is intermittent, which needs to be converted and stored for practical usage. , A supercapacitor is an important kind of energy storage device and is promising for various technological applications, − and continuous research efforts are now being made to improve its energy density. Recently, photoassisted charging has been reported as a novel approach to successfully increase the capacitance of supercapacitors with the utilization of solar energy. − Under proper illumination, these photoelectrochemical systems with semiconductor-based active materials could generate electron–hole pairs to participate in the charging and discharging processes of these supercapacitors and subsequently enhance their capacitances.…”

Optimizing nanostructure and constructing heterostructure via Mo/W incorporation to improve electrochemical properties of NiCoP for hybrid supercapacitors

“…The changes of surface potential and WF after the incorporation of high-valence elements were measured by KPFM at a nanometer scale. In the KPFM characterization, the WF of the sample (φ s ) is determined by the WF of the tip (φ t ) and the contact potential difference (CPD) between the tip and sample as described by the following equation [51,52]:…”

Recent advances in highly integrated energy conversion and storage system

“…Compared with nonillumination condition, the areal specific capacity of 1.452 C/cm 2 under light illumination increases by 44.8%, which is attributed to the synergistic effect of a built-in electric field enhancement and electron holes migration enhancement mechanism. 98 Moreover, the materials, including hexagonal-phase WO 3 and nanoporous Cu@Cu 2 O hybrid array, also have been developed for the photoelectrodes investigation in three-electrode system. And the results show 38 and 37.9% capacitance improvement under light illumination.…”

“…Besides, the 3D Cu foam@CuOx@NiCuOx nanosheets arrays combining photo‐sensitive characteristics of CuOx and pseudocapacitance characteristics of NiOx are fabricated and show a significant photoenhanced pseudocapacitance effect. Compared with nonillumination condition, the areal specific capacity of 1.452 C/cm 2 under light illumination increases by 44.8%, which is attributed to the synergistic effect of a built‐in electric field enhancement and electron holes migration enhancement mechanism 98 . Moreover, the materials, including hexagonal‐phase WO 3 and nanoporous Cu@Cu 2 O hybrid array, also have been developed for the photoelectrodes investigation in three‐electrode system.…”