Integrating Mixed Halide Perovskite Photocatalytic HI Splitting and Electrocatalysis into a Loop for Efficient and Robust Pure Water Splitting

Abstract

Developing a hydrogen economy to replace traditional fossil fuels is essential for sustainable human development. As two promising H2 production strategies, photocatalytic and electrocatalytic water splitting with large reaction energy barriers still face the great challenges of poor solar‐to‐hydrogen efficiency and large electrochemical overpotentials, respectively. Herein, a new strategy is proposed to disassemble the difficult pure water splitting into two parts that are easy to implement, namely mixed halide perovskite photocatalytic HI splitting for H2 production, and simultaneous electrocatalytic I3− reduction and O2 production. The efficient charge separation, abundant H2 production active sites, and a small HI splitting energy barrier contribute to the superior photocatalytic H2 production activity of MoSe2/MAPbBr3−xIx (CH3NH3+ = MA). Subsequent electrocatalytic I3− reduction and O2 production reactions only need a small voltage of 0.92 V to drive, which is far lower than that of the electrocatalytic pure water splitting (>1.23 V). The molar ratio of H2 (6.99 mmol g−1) to O2 (3.09 mmol g−1) produced during the first photocatalytic and electrocatalytic cycle is close to 2:1, and the continuous circulation of I3−/I− between the photocatalytic and electrocatalytic systems can achieve efficient and robust pure water splitting.

Lead‐Free Perovskite Cs2SnBr6/rGO Composite for Photocatalytic Selective Oxidation of 5‐Hydroxymethylfurfural to 2,5‐Diformylfuran

“…Besides, XPS valence spectrum coupled with UV-Vis absorption spectrum was applied to analyze the position of the valence band (VB) and band gap of Cs 2 SnBr 6 . As shown in Figure 1d, The VB position of Cs 2 SnBr 6 is 2.51 eV (À 7.01 eV, versus the vacuum level) relative to the normal hydrogen electrode (NHE), positive than that of reported MAPbBr 3 1.1 eV (À 5.6 eV) [48] and Cs 3 Bi 2 Br 9 2.17 eV (À 6.67 eV), [49] indicating its better oxidation ability. The bandgap energy (E g ) is calculated as 2.86 eV according to Kubelka-Munk theory, and so the CB position (conduction band) of Cs 2 SnBr 6 is determined as À 0.35 eV, enough to generate the reactive oxygen species.…”

Sonocatalytic oxidative desulfurization of diesel oil using a novel BiVO4/FeMn LDH nanocomposite

“…, where C o and C represent the sulfur content before and after UAODS treatment. The parameters such as the ultrasonic time (10-70 minutes), catalyst weight (0.003-0.03 g/15 ml), type of oxidant, H 2 O 2 /S molar ratio (4)(5)(6)(7)(8)(9)(10)(11)(12), the ratio of solvent/hydrotreated oil (0.5/1-2/1), and type of sonicator were studied based on the desulfurization treatment.…”

“…[1][2][3][4] Ongoing research is dedicated to exploring alternative energy options, including hydrogen production. 5,6 However, in the meantime, it is imperative to address the issues related to fossil fuels, such as the effective removal of sulfur. To comply with environmental regulations, most petroleum refineries should reduce the sulfur content in liquid fuel to low levels.…”

Insight into the complexation mechanism between a BiVO4photoanode and tartaric acid for efficient photoelectrochemical H2production

“…Utilizing photoelectrochemical (PEC) water splitting to achieve solar-to-hydrogen (STH) conversion is considered a promising solution for the impending energy and environmental crises. [1][2][3][4][5][6] Granted that the intrinsic merits of PEC water splitting (such as being clean and low-cost) make it an encouraging technique among various hydrogen (H 2 ) production methods, the sluggish water oxidation kinetics and the demanding thermodynamic reaction conditions greatly impact its practical application. [7][8][9][10][11][12][13] Therefore, replacing the water oxidation reaction with thermodynamically more favorable reactions becomes a desirable option for efficient PEC H 2 production.…”