Single‐Atom Doping and High‐Valence State for Synergistic Enhancement of NiO Electrocatalytic Water Oxidation

Small ◽  
2021 ◽  
pp. 2102448
Author(s):  
Meng Liu ◽  
Yujin Ji ◽  
Youyong Li ◽  
Pengfei An ◽  
Jing Zhang ◽  
...  
Keyword(s):  
Water Oxidation ◽  
Valence State ◽  
Single Atom ◽  
Synergistic Enhancement ◽  
High Valence State

Boosting water oxidation activity by tuning the proton transfer process of cobalt phosphonates in neutral solution

2020 ◽  
Vol 22 (25) ◽  
pp. 14255-14260
Author(s):  
Jiangquan Lv ◽  
Xiangfeng Guan ◽  
Muxin Yu ◽  
Xiaoyan Li ◽  
Yunlong Yu ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Transfer Process ◽  
Water Oxidation ◽  
Valence State ◽  
Neutral Solution ◽  
Oxidation Activity ◽  
Proton Coupled Electron Transfer ◽  
High Valence State ◽  
Neutral Conditions ◽  
Proton Transfer Process

We demonstrated that the ligand in cobalt phosphonate would benefit the proton-coupled electron transfer (PCET) processes and the formation of high valence state Co(IV), making it an efficient water oxidation electrocatalyst in neutral conditions.

scholarly journals Coordination modulation of iridium single-atom catalyst maximizing water oxidation activity

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Zhanwu Lei ◽  
Wenbin Cai ◽  
Yifei Rao ◽  
Kuan Wang ◽  
Yuyuan Jiang ◽  
...  
Keyword(s):  
High Activity ◽  
Current Density ◽  
Water Oxidation ◽  
Distribution Density ◽  
High Surface ◽  
Single Atom ◽  
Surface Distribution ◽  
Oxidation Activity ◽  
Nanosheet Arrays ◽  
A Current

AbstractSingle-atom catalysts (SACs) have attracted tremendous research interests in various energy-related fields because of their high activity, selectivity and 100% atom utilization. However, it is still a challenge to enhance the intrinsic and specific activity of SACs. Herein, we present an approach to fabricate a high surface distribution density of iridium (Ir) SAC on nickel-iron sulfide nanosheet arrays substrate (Ir1/NFS), which delivers a high water oxidation activity. The Ir1/NFS catalyst offers a low overpotential of ~170 mV at a current density of 10 mA cm−2 and a high turnover frequency of 9.85 s−1 at an overpotential of 300 mV in 1.0 M KOH solution. At the same time, the Ir1/NFS catalyst exhibits a high stability performance, reaching a lifespan up to 350 hours at a current density of 100 mA cm−2. First-principles calculations reveal that the electronic structures of Ir atoms are significantly regulated by the sulfide substrate, endowing an energetically favorable reaction pathway. This work represents a promising strategy to fabricate high surface distribution density single-atom catalysts with high activity and durability for electrochemical water splitting.

scholarly journals Single-atom cobalt-hydroxyl modification of polymeric carbon nitride for highly enhanced photocatalytic water oxidation: ball milling increased single atom loading

2022 ◽  
Author(s):  
Fei Yu ◽  
Tingting Huo ◽  
Quanhua Deng ◽  
Guoan Wang ◽  
Yuguo Xia ◽  
...  
Keyword(s):  
Ball Milling ◽  
Water Splitting ◽  
Oxygen Evolution ◽  
Oxygen Evolution Reaction ◽  
Water Oxidation ◽  
Carbon Nitride ◽  
Single Atom ◽  
Overall Water Splitting ◽  
Polymeric Carbon

Expediting the oxygen evolution reaction (OER) is the key to achieving efficient photocatalytic overall water splitting. Herein, single-atom Co−OH modified polymeric carbon nitride (Co-PCN) was synthesized with single-atom loading increased...

ChemInform Abstract: Two-Dimensional Charge Disproportionation of the Unusual High Valence State Fe4+in a Layered Double Perovskite.

ChemInform ◽  
2015 ◽  
Vol 46 (40) ◽  
pp. no-no
Author(s):  
Yoshiteru Hosaka ◽  
Noriya Ichikawa ◽  
Takashi Saito ◽  
Pascal Manuel ◽  
Dmitry Khalyavin ◽  
...  
Keyword(s):  
Valence State ◽  
Double Perovskite ◽  
Two Dimensional ◽  
Charge Disproportionation ◽  
High Valence State

Distributions and Species of MnOx Included in MnOx/TiO2 Catalysts for Denitration at Low Temperature

2013 ◽  
Vol 743-744 ◽  
pp. 269-274 ◽  
Author(s):  
De Fang ◽  
Feng He ◽  
Jun Lin Xie ◽  
Hua Hu ◽  
Zai Ying Shi
Keyword(s):  
Low Temperature ◽  
Valence State ◽  
Nitrogen Atmosphere ◽  
Catalytic Process ◽  
Synthesis Methods ◽  
Titration Method ◽  
Cement Production ◽  
Calcination Temperatures ◽  
Dispersion Degree ◽  
High Valence State

MnOx/TiO2 catalysts are active and stable at low temperature, and it is appropriate for cement production to enforce NOx emissions. In this study, the denitration process was promoted by the transformation of a variety of MnOx forms in the SCR reaction. The efficiency and selectivity of catalysts depended on the form and dispersion degree of MnOx. By changing the precursors, calcination temperatures, synthesis methods and calcination atmospheres, a series of MnOx/TiO2 catalysts were prepared. The contents and distributions of Mn2+, Mn3+ and Mn4+ in catalysts were tested through the titration method. The titration results showed that the content of Mn4+ was the highest during the precursor was Mn (NO3)2, while the content of Mn2+ in the catalysts calcinated in nitrogen atmosphere was the highest. The mechanisms of different MnOx states in the catalytic process were discussed. It was found that a mixture of more MnOx with low valence state and less MnOx with high valence state were beneficial to the catalytic process.

scholarly journals Zero-valent Palladium Single-Atoms Catalysts Confined in Black Phosphorus for Efficient Semi-hydrogenation

2020 ◽  
Author(s):  
cheng chen ◽  
Ou Wei ◽  
Yam Kahmeng ◽  
Xi Shibo ◽  
Zhao Xiaoxu ◽  
...  
Keyword(s):  
Atomic Layer ◽  
Pd Nanoparticles ◽  
Black Phosphorus ◽  
Single Atom ◽  
Chemical Transformations ◽  
Confined Space ◽  
Organic Transformations ◽  
Single Atoms ◽  
Wide Range ◽  
High Valence State

<p></p><p>Single-atom catalysts (SACs) represent a new frontier in heterogeneous catalysis due to their remarkable catalytic properties and maximized atomic utilization. However, single atoms often bond to the support with polarized electron density and thus exhibit a high valence state, limiting their catalytic scopes in many chemical transformations. Here, we demonstrated that two-dimensional (2D) black phosphorus (BP) act as giant phosphorus (P) ligand to confine a high density of single atoms (eg, Pd1, Pt1) via atomic layer deposition. Unlike other 2D materials, BP with relatively low electronegativity and buckled structure favors the strong confinement of robust zero-valent palladium SACs in the vacancy site. Metallic Pd1/P SAC shows a highly selective semi-hydrogenation of phenylacetylene towards styrene, outperforming high-valence Pt1/P SAC, and also distinct from metallic Pd nanoparticles that facilitate the formation of fully hydrogenated products. Our DFT calculations reveal that Pd atom forms covalent-like bonding with adjacent P atoms, wherein H atoms tend to adsorb over electron-rich region for the subsequent hydrogenation. Zero-valent Pd in the confined space favors a larger energy gain for the synthesis of partially-hydrogenated product over the fully-hydrogenated one. Our work provides a new route towards the synthesis of zero-valent SACs on BP for a wide range of organic transformations. <br></p><p></p>

Sign in / Sign up

Export Citation Format

Share Document