Light/Electricity Energy Conversion and Storage for a Hierarchical Porous In₂S₃@CNT/SS Cathode towards a Flexible Li‐CO₂ Battery

Abstract

Ap hotoinduced flexible Li-CO 2 battery with welldesigned, hierarchical porous,a nd free-standing In 2 S 3 @CNT/ SS (ICS) as abifunctional photoelectrode to accelerate both the CO 2 reduction and evolution reactions (CDRR and CDER) is presented. The photoinduced Li-CO 2 battery achieved ar ecord-high discharge voltage of 3.14 V, surpassing the thermodynamic limit of 2.80 V, and an ultra-low charge voltage of 3.20 V, achieving around trip efficiency of 98.1 %, which is the highest value ever reported (< 80 %) so far.T hese excellent properties can be ascribed to the hierarchical porous and freestanding structure of ICS,a sw ell as the key role of photogenerated electrons and holes during discharging and charging processes.Amechanism is proposed for pre-activating CO 2 by reducing In 3+ to In + under light illumination. The mechanism of the bifunctional light-assisted process provides insight into photoinduced Li-CO 2 batteries and contributes to resolving the major setbacks of the system.

Capturing Visible Light in Low‐Band‐Gap C4N‐Derived Responsive Bifunctional Air Electrodes for Solar Energy Conversion and Storage

“…0.59 V), which was lower than the theoretical value (ca. 0.94 V) (Figure S25), similar to other types of batteries caused by the large overpotentials of both anode and cathode [17, 26, 38] . As shown in Figure 6 e,f, the battery was fully discharged to 0 V for releasing all electric energy and subsequently galvanostatically charged at 0.05 mA cm −2 under intermittent visible‐light illumination.…”

“…Mott‐Schottky (M‐S) measurement was conducted at a frequency of 1 kHz (Figure 2 d). The observed positive slope of the M‐S plot indicated the n‐type semiconducting character of C 4 N [17] . The conduction band (CB) value ( E CB ) of C 4 N was calculated to be −0.73 V versus the normal hydrogen electrode (NHE).…”

“…Capturing the sunlight in electrochemical energy devices (e.g. aqueous secondary air batteries) for direct conversion/storage of solar energy is a feasible option to resolve this drawback [6, 13–19] . Such photo‐assisted energy system can be promising for various applications such as the stationary solar battery system [20–22] .…”

Capturing Visible Light in Low‐Band‐Gap C4N‐Derived Responsive Bifunctional Air Electrodes for Solar Energy Conversion and Storage

“…The water contact angle of CC was 145.63°, beneficial for the ORR proceeding at the triple‐phase interface of electrocatalyst‐electrolyte‐gas (Figure S10). As seen from Figure 3 c,d, C 4 N@CC exhibited a positive onset potential (0.80 V) and much larger catalytic current density compared to C 4 N/CP along with good electrocatalytic stability (Figure S11), although the light exposure caused negligible influence on the ORR performance of C 4 N@CC and produced weak photocurrent response due to the severe recombination of photogenerated electron‐hole pairs in the C 4 N@CC [17] . Of note, the activities of bare CP and CC substrates were low for both ORR and OER.…”

Magnetic and Optical Field Multi-Assisted Li-O2 Batteries with Self-Regulated Charge and Discharge

“…The Nyquist plot of NiO/FNi MF (5 mT) light displays a much larger gradient, indicating a faster diffusion rate compared with NiO/FNi MF (0 mT) light. On the basis of the Nyquist plots30 , the Li + diffusion coe cients' ratio of NiO/FNi MF light and NiO/FNi NMF light is determined to be 5:1, demonstrating a superior kinetics under MF for Li + diffusion.…”