Light-Driven Fuel Cell with a 2D/3D Hierarchical CuS@MnS Z-Scheme Catalyst for H₂O₂ Generation

Abstract

A photoelectrocatalytic (PEC) oxygen reduction reaction (ORR) strategy with fuel-efficient and cost-effective catalysts for on-demand hydrogen peroxide (H 2 O 2 ) production is booming as an attractive alternative to the conventional anthraquinone process. Herein, we constructed a novel twodimensional (2D)/three-dimensional (3D) hierarchical CuS@MnS p−p Z-scheme catalyst with full spectrum absorption and strong coupling interface by regulating the crystal structure, morphology, and photocharge transfer mechanism, which was used as a photocathode for PEC synthesis of H 2 O 2 with a yield of 1.65 mM within 180 min. Taking advantage of a coupling strategy with Sn 3 O 4 /Ni foam, the as-prepared two-compartment cell with water oxidation reaction and ORR exhibited boosted activity and stability for the dual production of H 2 O 2 . An energy-saving H 2 O 2 generation system was also constructed with a direct hydrazine/O 2 fuel cell, realizing the significant advantage in reducing electricity consumption during the H 2 O 2 synthesis. Moreover, the onsite generation of H 2 O 2 remarkably accelerated the degradation of pollutants via a cascade heterogeneous Fenton reaction with a Fe anode. This work provides a new strategy for designing a multifunctional PEC system for the production of high-value chemicals, energy recovery, and pollutant degradation.

Host–Guest Interaction Mediated Perovskite@Metal–Organic Framework Z-Scheme Heterojunction Enabled Paper-Based Photoelectrochemical Sensing

“…The DMPO-•O 2 – signal could be observed for MAPbBr 3 QDs under illumination for 8 min, which was attributed to its suitable E CB potential (Figure b). With the formation of the MAPbBr 3 @Cu 3 (BTC) 2 heterojunction, an energetic light-induced signal of DMPO-•O 2 – was detected than that of single MAPbBr 3 QDs, suggesting that the photogenerated electrons mainly accumulated on the CB of MAPbBr 3 QDs rather than Cu 3 (BTC) 2 MOF . Similarly, MAPbBr 3 @Cu 3 (BTC) 2 exhibited much stronger signals of DMPO-•O than pristine Cu 3 (BTC) 2 MOF, implying that the holes mainly stayed in the VB of Cu 3 (BTC) 2 MOF instead of MAPbBr 3 QDs (Figure c) .…”

Effect of Partial Cation Replacement on Anode Performance of Sodium-Ion Batteries

“…This indicates the presence of both +2 and +3 valence states of Co. In the core energy-level spectrum of Mn 2p 3/2 , the peaks at 641.4 eV (blue line) correspond to Mn 2+ [46]. The satellite peaks at 647.1 eV (Yellow line) are also characteristic of Mn 2+ .…”