DIAMOND AND RELATED MATERIALS
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2024
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IF 4.3
Zixiang Hao,Yang Chen,Linrui Wang,Yuxuan Lu,Chengli He,Mingyan Wang,Xiaoli Cui
Elemental engineering has been employed to adjust molecular framework and electronic configuration of γ-graphyne for rapid lithium storage. Here, we construct a quasi-pyridinic nitrogen/sulfur co-doped γ-graphyne (N/S-GY) via a mechanochemical strategy and reveal its lithium storage behavior by quantitative kinetics analysis and theoretical calculations. The internal pyridinic-N atoms create rhombic channels for Li + passing through, while sulfur dopants anchored with alkynyl groups induce electron cloud rearrangement to facilitate intralayer Li + diffuse between C 12 -triangular channels and interlayer transfer through open rhombic channels. As a result, the as-prepared N/S-GY exhibits a high reversible capacity of 1003 mAh g −1 at 50 mA g −1 after 150 cycles, with Li + diffusion coefficient up to 2.6 × 10 −12 cm 2 s −1 , both of which are larger than that of N-doped γ-graphyne. This work highlights synergistic effect of sulfur and nitrogen co-doping in alkynyl carbon and inspires bottom-up heteroatom modification in framework design.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
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2021
·Vol. 50
·期 42
·15422-15432
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IF 4.39
Dong Qiu,Chengli He,Yuxuan Lu,Qiaodan Li,Yang Chen,Xiaoli Cui
Photoelectrochemical water splitting is an excellent strategy for hydrogen generation and it is pivotal to the development of photoanodes with sufficient sunlight harvesting, rapid charge separation, and enhanced electron injection efficiency. In this work, we rationally constructed a γ-graphyne/TiO2 (GY/TiO2) p–n heterojunction in which p-type γ-graphyne nanosheets were distributed in the three-dimensional space surrounding TiO2 nanotube arrays. The GY/TiO2 photoanode achieves a photocurrent density of 0.75 mA cm−2 at 1.23 V (vs. RHE), 1.7 times that of bare TiO2, and extends the electron lifetime of TiO2 from 0.51 to 1.16 ms. The improvement arises from moderate γ-graphyne modification, contributing to broadened light absorption, the suppressed recombination of electron–hole pairs, an increase in charge transfer, and a higher injection efficiency of surface electrons. This work provides a reliable approach for the utilization and conversion of sustainable solar energy.
研究领域:
材料科学
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能源转换与存储
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光催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Catalysis
·
2023
·
IF 12.9
Chao Zhang,Yingqiang Li,Yue Xie,Zhanjiang Yu,Xin Wan,Xinzhi Wang,Jiaan He,Junlang Li,Zhenguo Chen,Xiaoyong Li,Xiaohui Yi,Zhaoli Wang,Guang-Guo Ying,Dionysios D. Dionysiou,Mingzhi Huang
Selective hydrodehalogenation and hydrodearomatization of toxic chlorophenols into value-added chemicals represents a grand challenge for their efficient reutilization. For this purpose, single-atom catalysts (SACs) could be a strategy with relatively high catalytic selectivity and atom utilization but suffer from the catalytic limitation caused by low metal loading densities. Graphdiyne and γ-graphyne are considered promising substrates of SACs with excellent catalytic properties. Additionally, their quantum dots with nanometer size are expected to supply numerous surface anchoring sites and large atom spacing to confine metal cations to synthesize high-loading SACs. Here we report a synthesis approach for high-loading Ru SACs anchored on graphdiyne/γ-graphyne quantum dots (GDQD-Ru/GNQD-Ru), which exhibit remarkably higher turnover frequency (TOF) and selectivity (>99%) of hydrodehalogenation and hydrodearomatization of chlorophenols than graphdiyne/γ-graphyne nanosheet-based Ru SACs and nanoparticles. There is no significant selectivity decrease in chlorophenol transformation by GDQD-Ru/GNQD-Ru observed in 5 catalyst reuse cycles. GDQD-Ru/GNQD-Ru contribute to nearly exclusive hydrodehalogenation and hydrodearomatization without altering any other bonds in chlorophenols. Experimental results and theoretical calculations reveal that GDQD-Ru is more prone to lower energies of rate-limiting steps in H2-driven chlorophenol transformation than GNQD-Ru. The results confirm that graphdiyne/γ-graphyne quantum dots play crucial roles in facilitating the metal atom loading of SACs. Ru loadings are 27.6 and 16.0 wt % in GDQD-Ru/GNQD-Ru, approximately 7-fold and 4-fold higher than reported Ru SACs, respectively. This study provides mechanistic insights toward the roles of high-loading Ru SACs on sp- and sp2-hybridized carbonaceous substrates in selective hydrodehalogenation and hydrodearomatization.
研究领域:
化学
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催化科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
VACUUM
·
2023
·
IF 4
Zihan Wang,Xiaoqing Ma,Qiaodan Li,Xinyao Tian,Jilei Si,Mauricio A. Melo
Photoelectrochemical (PEC) water splitting is a viable method for converting renewable solar energy into storable chemical energy. Herein, the newly emerged two-dimensional sp- and sp 2 -carbon hybridized graphyne sheets were successfully coupled with thin film-like arrays of titanium dioxide nanorods , forming an efficient 2D-1D heterojunction . The microstructure and composition of obtained γ-graphyne/TiO 2 films were well characterized. And enhanced photoelectrochemical properties were demonstrated. The γ-graphyne/TiO 2 photoelectrode achieves a photocurrent density of 1.31 mA/cm 2 at 1.23 V ( vs. RHE), which is 1.7 times over that of pristine titanium dioxide. An improvement of photoconversion efficiency by 2.2 folds was observed. The high PEC activity of γ-graphyne/TiO 2 originates from band alignment and interfacial junction between π-conjugated graphyne sheets and TiO 2 nanostructure , greatly promoting charge transfer and diminishing defective excitation and recombination. By virtue of the γ-graphyne nanosheets , largely increased number of useful photons and catalytic active sites are triggered. This work provides a reference for the photoelectrochemical application of semiconductive γ-graphyne and a specific and proven method for the utilization of solar energy.
研究领域:
材料科学
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纳米技术
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可再生能源
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光化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）