Synergistic effects of Co single atoms and Co nanoparticles for electrocatalytic nitrate-to-ammonium conversion in strongly acidic wastewater

Applied Catalysis B Environment and Energy, Год журнала: 2024, Номер 363, С. 124812 - 124812

Опубликована: Ноя. 10, 2024

Язык: Английский

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Isolated Rhodium Atoms Activate Porous TiO₂ for Enhanced Electrocatalytic Conversion of Nitrate to Ammonia

Advanced Science, Год журнала: 2024, Номер 12(2)

Опубликована: Ноя. 18, 2024

Abstract The direct electrochemical reduction of nitrate to ammonia is an efficient and environmentally friendly technology, however, developing electrocatalysts with high activity selectivity remains a great challenge. Single‐atom catalysts demonstrate unique properties exceptional performance across range catalytic reactions, especially those that encompass multi‐step processes. Herein, straightforward cost‐effective approach introduced for synthesizing single‐atom dispersed Rh on porous TiO 2 spheres (Rh 1 ‐TiO ), which functions as electrocatalyst the electroreduction NO 3 − NH . synthesized catalyst achieve maximum Faradaic efficiency (FE) 94.7% yield rate 29.98 mg h −1 cat at −0.5 V versus RHE in 0.1 M KOH+0.1 KNO electrolyte, significantly outperforming not only undoped but also Ru, Pd, Ir doped titania catalysts. Density functional theory calculations reveal incorporation single atom enhances charge transfer between adsorbed active site. atoms serve highly site reaction (NO RR), activates adjacent Ti sites through optimizating electronic structure, thereby reducing energy barrier rate‐limiting step. Consequently, this results substantial enhancement RR performance. Furthermore, synthetic method has potential be extended other scaled up commercial applications.

Язык: Английский

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Atomic Scale Cooperativity of Alloy Nanostructures for Efficient Nitrate Electroreduction to Ammonia in Neutral Media

Advanced Functional Materials, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 25, 2024

Abstract Electrochemical nitrate reduction reaction (NO 3 RR) offers a route to balanced nitrogen cycle and sustainable ammonia production. However, unsatisfied performance in neutral media arising from competitive hydrogen evolution inefficient hydrogenation impede the further applications of NO RR. Herein, rational design RuNi alloy nanostructures is reported. Benefited synergism effect between Ru Ni, 20 Ni 80 exhibits high NH Faradaic efficiency 98.02% at −0.35 V (vs reversible electrode (RHE)) large yield rate 27.88 mg cat −1 h −0.65 RHE). Importantly, atomic scale cooperation active sites endows close‐to‐unity selectivity via HNO * pathway. Theoretical calculations have revealed that interactions optimize electronic structures alloy, where with enhanced electroactivity improve generation hydrogens more electron‐rich facilitate nitrate. Accordingly, adsorption strengths key intermediates become stronger energy barriers RR are reduced guarantee efficient Furthermore, flow‐type reactor coupled coprecipitation established achieve continuous recovery as struvite.

Язык: Английский

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Pulsed Electrolysis in Membrane Electrode Assembly Architecture for Enhanced Electrochemical Nitrate Reduction Reaction to Ammonia

ACS Catalysis, Год журнала: 2024, Номер unknown, С. 18223 - 18236

Опубликована: Ноя. 26, 2024

Electrochemical nitrate reduction reaction (NO3–RR) to ammonia offers a promising solution environmental and energy challenges, converting ubiquitous pollutant in aquatic environments into carbon-free carrier essential chemical feedstock. While considerable research has focused on electrocatalyst development, relatively less attention been given device engineering electroanalytical techniques that play crucial roles enhancing the performance of electrocatalytic NO3–RR, especially at such low concentrations. Here, CuxRuy alloy catalysts were synthesized, their was investigated by using various H-type membrane-electrode-assembly (MEA) configurations. The results revealed poor NO3–RR NO3– concentrations (0.01 M) H cells due mass transfer loss, promoting competing hydrogen evolution reaction. Pulsed electrolysis leveraged as an effective strategy enhance yield rate (3-fold) Faradaic efficiency (FE) (2-fold) compared potentiostatic (i.e., constant voltage) condition concentrations, primarily impacting local microenvironment. Additionally, MEA cell constructed with anionic bipolar membranes, comparative study conducted examining voltage, selectivity, efficiency. findings exhibited membrane type significantly influences voltage system Notably, CuRu catalyst anion exchange achieved FE exceeding 90% 200 mA cm–2 highest NH3 5.74 ± 0.27 mmol h–1 stability over 100 h assessed 600 cm–2. insights gained from this work could inform rational design electrochemical enhanced catalytic

Язык: Английский

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Advanced Ruthenium‐Based Electrocatalysts for NO_x Reduction to Ammonia

Advanced Materials, Год журнала: 2024, Номер unknown

Опубликована: Дек. 15, 2024

Ammonia (NH

Язык: Английский

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