Reinforcing CoO Covalency via Ce(4f)─O(2p)─Co(3d) Gradient Orbital Coupling for High‐Efficiency Oxygen Evolution

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(30)

Published: April 18, 2023

Rare-earth (RE)-based transition metal oxides (TMO) are emerging as a frontier toward the oxygen evolution reaction (OER), yet knowledge regarding their electrocatalytic mechanism and active sites is very limited. In this work, atomically dispersed Ce on CoO successfully designed synthesized by an effective plasma (P)-assisted strategy model (P-Ce SAs@CoO) to investigate origin of OER performance in RE-TMO systems. The P-Ce SAs@CoO exhibits favorable with overpotential only 261 mV at 10 mA cm-2 robust electrochemical stability, superior individual CoO. X-ray absorption spectroscopy situ Raman reveal that Ce-induced electron redistribution inhibits CoO bond breakage CoOCe unit site. Theoretical analysis demonstrates gradient orbital coupling reinforces covalency Ce(4f)─O(2p)─Co(3d) site optimized Co-3d-eg occupancy, which can balance adsorption strength intermediates turn reach apex theoretical maximum, excellent agreement experimental observations. It believed establishment Ce-CoO set basis for mechanistic understanding structural design high-performance catalysts.

Language: Английский

---

Engineering 3d–2p–4f Gradient Orbital Coupling to Enhance Electrocatalytic Oxygen Reduction

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(42)

Published: Sept. 10, 2022

The development of highly efficient and economical materials for the oxygen reduction reaction (ORR) plays a key role in practical energy conversion technologies. However, intrinsic scaling relations exert thermodynamic inhibition on realizing active ORR electrocatalysts. Herein, novel feasible gradient orbital coupling strategy tuning performance through construction Co 3d-O 2p-Eu 4f unit sites Eu2 O3 -Co model is proposed. Through coupling, pristine ionic property between Eu O atoms assigned with increased covalency, which optimizes eg occupancy sites, weakens OO bond, thus ultimately breaking relation *OOH *OH at Co-O-Eu sites. optimized catalyst displays onset half-wave potential 1.007 0.887 V versus reversible hydrogen electrode, respectively, are higher than those commercial Pt/C most Co-based catalysts ever reported. In addition, found to possess superior selectivity durability. It also reveals better cell noble-metal Zn-air batteries terms high power/energy densities long cycle life. This study provides new perspective electronic modulation by 3d-2p-4f coupling.

Language: Английский

---

Plasma‐induced Mo‐doped Co₃O₄ with enriched oxygen vacancies for electrocatalytic oxygen evolution in water splitting

Carbon Energy, Journal Year: 2022, Volume and Issue: 5(3)

Published: Oct. 27, 2022

Abstract Heteroatomic substitution and vacancy engineering of spinel oxides can theoretically optimize the oxygen evolution reaction (OER) through charge redistribution d ‐band center modification but still remain a great challenge in both preparation catalytic mechanism. Herein, we proposed novel efficient Ar‐plasma (P)‐assisted strategy to construct heteroatom Mo‐substituted vacancies enriched hierarchical Co 3 O 4 porous nanoneedle arrays situ grown on carbon cloth (denoted P‐Mo‐Co @CC) improve OER performance. technology efficiently generate sites at surface hydroxide, which induces anchoring Mo anion salts electrostatic interaction, finally facilitating atoms formation surface. The @CC affords low overpotential only 276 mV 10 mA cm −2 for OER, is 58 superior that Mo‐free surpasses commercial RuO 2 catalyst. robust stability satisfactory selectivity (nearly 100% Faradic efficiency) are also demonstrated. Theoretical studies demonstrate with variable valance states regulates atomic ratio 3+ /Co 2+ increases number vacancies, thereby inducing tuning , adsorption energy intermediates (e.g., *OOH) during OER. Furthermore, two‐electrode OER//HER electrolyzer equipped as anode displays operation potential 1.54 V deliver current density exhibits good reversibility anticurrent fluctuation ability under simulated real supply conditions, demonstrating water electrolysis.

Language: Английский

---

Single-Atom Yttrium Engineering Janus Electrode for Rechargeable Na–S Batteries

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(41), P. 18995 - 19007

Published: Oct. 10, 2022

The development of rechargeable Na-S batteries is very promising, thanks to their considerably high energy density, abundance elements, and low costs yet faces the issues sluggish redox kinetics S species polysulfide shuttle effect as well Na dendrite growth. Following theory-guided prediction, rare-earth metal yttrium (Y)-N4 unit has been screened a favorable Janus site for chemical affinity polysulfides electrocatalytic conversion, reversible uniform deposition. To this end, we adopt metal-organic framework (MOF) prepare single-atom hybrid with Y single atoms being incorporated into nitrogen-doped rhombododecahedron carbon host (Y SAs/NC), which features properties sodiophilicity sulfiphilicity thus presents highly desired electrochemical performance when used sodium anode sulfur cathode full cell. Impressively, cell capable delivering capacity 822 mAh g-1 shows superdurable cyclability (97.5% retention over 1000 cycles at current density 5 A g-1). proof-of-concept three-dimensional (3D) printed pouch validate potential practical applications such batteries, shedding light on promising cells future application in storage or power batteries.

Language: Английский

---

Neodymium‐Evoked Valence Electronic Modulation to Balance Reversible Oxygen Electrocatalysis

Advanced Energy Materials, Journal Year: 2022, Volume and Issue: 13(2)

Published: Nov. 23, 2022

Abstract Suffering from the competition adsorption between oxygen reduction reaction (ORR) and evolution (OER), development of high‐efficiency electrocatalysts with bifunctional properties still remains a challenge. Herein, novel effective neodymium‐evoked valence electronic perturbation strategy to improve balance reversible electrocatalysis metallic cobalt sites is proposed. To heighten coupling Nd Co, metal‐organic‐framework‐induced method chosen prepare target catalyst atomic Nd‐doped Co on an N‐doped carbon substrate. The as‐prepared presents excellent electrocatalytic low overpotential 288 mV at 10 mA cm −2 for OER high half‐wave potential 0.85 V ORR. robust stabilities both ORR are also proven. electrochemical in situ Raman spectra confirm surface dynamic change transformation intermediates by noting formation Co–OOH. Theoretical calculations verify that balanced owing strong 3d‐Nd 4f orbital effect below Fermi level. Moreover, practicability further demonstrated solid‐state rechargeable Zn‐Air batteries, which exhibit large power density long cycling life.

Language: Английский

---

Heteroatom‐Driven Coordination Fields Altering Single Cerium Atom Sites for Efficient Oxygen Reduction Reaction

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(28)

Published: April 4, 2023

For current single-atom catalysts (SACs), modulating the coordination environments of rare-earth (RE) single atoms with complex electronic orbital and flexible chemical states is still limited. Herein, cerium (Ce) SAs supported on a P, S, N co-doped hollow carbon substrate (Ce SAs/PSNC) for oxygen reduction reaction (ORR) are reported. The as-prepared Ce SAs/PSNC possesses half-wave potential 0.90 V, turnover frequency value 52.2 s

Language: Английский

---

Improving the Oxygen Evolution Activity of Layered Double‐Hydroxide via Erbium‐Induced Electronic Engineering

Small, Journal Year: 2022, Volume and Issue: 19(5)

Published: Nov. 29, 2022

Layered double-hydroxide (LDH) has been considered an important class of electrocatalysts for the oxygen evolution reaction (OER), but adsorption-desorption behaviors intermediates on its surface still remain unsatisfactory. Apart from transition-metal doping to solve this electrocatalytic problem LDH, rare-earth (RE) species have sprung up as emerging dopants owing their unique 4f valence-electronic configurations. Herein, Er is chosen a RE model improve OER activity LDH via constructing nickel foam supported Er-doped NiFe-LDH catalyst (Er-NiFe-LDH@NF). The optimal Er-NiFe-LDH@NF exhibits low overpotential (191 mV at 10 mA cm-2 ), high turnover frequency (0.588 s-1 and activation energy (36.03 kJ mol-1 which are superior Er-free sample. Electrochemical in situ Raman spectra reveal facilitated transition Ni-OH into Ni-OOH promoted kinetics through effect. Theoretical calculations demonstrate that introduction facilitates spin crossover valence electrons by optimizing d band center NiFe-LDH, leads GO -GHO closer kinetic volcano balancing bonding strength *O *OH. Moreover, presents practicability electrochemical water-splitting devices with driving potential well-extended period.

Language: Английский

---

Rare earth-based nanomaterials in electrocatalysis

Coordination Chemistry Reviews, Journal Year: 2023, Volume and Issue: 489, P. 215204 - 215204

Published: May 3, 2023

Language: Английский

---

Engineering the strong metal support interaction of titanium nitride and ruthenium nanorods for effective hydrogen evolution reaction

Applied Catalysis B Environment and Energy, Journal Year: 2022, Volume and Issue: 317, P. 121796 - 121796

Published: July 27, 2022

Language: Английский

---

State-of-the-art single-atom catalysts in electrocatalysis: From fundamentals to applications

Nano Energy, Journal Year: 2023, Volume and Issue: 113, P. 108570 - 108570

Published: May 29, 2023

Language: Английский

---