Inorganics
·
2023
·Vol. 11
·期 6
·243
·
IF 2.9
Xiantun Huang,Chenglin Lu,Yun Li,Haimei Tang,Xingqing Duan,Kuikui Wang,Haizhen Liu
MgH2has a high hydrogen content of 7.6 wt% and possesses good reversibility under normal conditions. However, pristine MgH2requires a high temperature above 300 °C to release hydrogen, with very slow kinetics. In this work, we utilized Ti3CN MXene to reduce the operating temperature and enhance the kinetics of MgH2. The initial temperature of MgH2decomposition can be lowered from 322 °C for pristine MgH2to 214 °C through the employment of Ti3CN. The desorbed MgH2+ 7.5 wt% Ti3CN can start absorption at room temperature, while the desorbed pristine MgH2can only start absorption at 120 °C. The employment of Ti3CN can significantly improve the hydrogen release kinetics of MgH2, with the desorption activation energy decreasing from 121 to 80 kJ mol−1. Regarding thermodynamics, the desorption enthalpy changes of MgH2and MgH2+ 7.5 wt% Ti3CN were 79.3 and 78.8 kJ mol−1, respectively. This indicates that the employment of Ti3CN does not alter the thermal stability of MgH2. Phase evolution studies through the use of X-ray diffraction and electron diffraction both confirm that Ti3CN remains stable during the hydrogen release and uptake process of the composite. This work will help understand the impact of a transition metal carbonitride on the hydrogen storage of MgH2.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2025
·
IF 12.1
Mingli Qin,Jiale Ai,Artem V. Kuklin,Ruijun Zhang,Jiahui Hou,Yiming Zhao,Han Zhang,Jian Zhang,Hans Ågren,Lingfeng Gao,Youju Huang
As a typical hetero-MXene, Ti 3 CN MXene has attracted great attentions owing to its ultrafast carrier dynamic and unique nonlinear optical response. However, the photo-response of pristine Ti 3 CN is unsatisfied due to the fast carrier recombination. Herein, multi-layer Ti 3 CN MXene is modified with well-dispersed Bi quantum dots, where the Ti 3 CN@Bi heterojunction can not only tune the optical absorption but also introduce energy transfer channels. The built-in electric field endows Ti 3 CN@Bi self-powered response behavior and the performance can be further enhanced by tuning external conditions. As demonstrated, the Ti 3 CN@Bi-based photodetectors exhibit high photocurrent density (18.24 µA cm −2 ) and excellent photoresponsivity (18.32 mA W −1 ). In addition, the device shows fast response and outstanding stability (0.002% for each cycle), holding great potentials for practical applications. Hence, this work not only highlights the broad prospects of MXene-based heterojunction, but also provides great value for other optoelectronic device applications.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ChemistrySelect
·
2024
·Vol. 9
·期 18
·e202305086
·
IF 1.9
XuKun Qian,ZeFeng Zhao,RuiHua Zhang,ChangBai Yu
Graphical The adsorption capacity of Pb(II) ion for accordion-like Ti 3 CN Mxene is significantly increased after alkalization treatment. The maximum adsorption capacity of the alkalized Ti 3 CN MXene is up to 87.4 mg ⋅ g −1 , and the adsorption ratio reaches 96.6 %. The adsorption process is mainly controlled by chemical adsorption and belongs to surface monolayer adsorption. The presence of poisonous Pb(II) ions in water resources has raised global health concerns. Herein, the adsorption performance of accordion-like Ti 3 CN MXene for Pb(II) ions was investigated for the first time. Batch experiments were carried out by varying modifications, pH values, initial Pb(II) concentrations, adsorption time and temperatures. The results prove that the alkalized-Ti 3 CN shows enhanced adsorption performance. Although the temperature effect is insignificant, the Pb(II) adsorption is strongly pH-dependent. The maximum Pb(II) adsorption capacity of alkalized −Ti 3 CN is about 2.5 times higher than that of activated carbon. The adsorption ratio of Pb(II) is up to 96.6 %. The adsorption capacity increases with increasing the initial concentration of Pb(II). The alkalized-Ti 3 CN adsorbs Pb(II) very quickly and the adsorption equilibrium is nearly achieved within 70 minutes. The adsorption follows the quasi-second-order kinetic model as well as the Langmuir model, and is mainly controlled by chemical adsorption. It is preliminarily concluded that Pb(II) replaces Na(I) of the −ONa functional groups on the alkalized-Ti 3 CN surfaces. This study proves the alkalized-Ti 3 CN MXene has potential application for the purification treatment of wastewater contaminated with Pb(II) ions.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ChemistrySelect
·
2022
·Vol. 7
·期 8
·e202104176
·
IF 2.307
Zefeng Zhao,Xukun Qian,Hailin Zhu,Yigao Miao,Hua Ye
Graphical The stability of accordion-like Ti 3 CN MXene in aqueous solutions, ethanol and N , N -dimethylformamide has been investigated. It is revealed Ti 3 CN exhibits limited stability in the aqueous solutions, and transforms to anatase TiO 2 nanoparticles in pH=1 and 7 solutions, and amorphous TiO 2 nanowires in pH=14 solution after a 7-day test at 25 °C. This transformation accelerates when the testing temperature increased to 80 °C. Meanwhile, Ti 3 CN shows excellent stability in ethanol and N , N -dimethylformamide after a 7-day test. MXene materials have shown promising applications in selective separation membranes and many other fields. However, their structural stability which is critically important to applications in the presence of aqueous solutions and organic solvents remains largely unexplored. In this work, we have conducted a systematic study on the synthesis of accordion-like Ti 3 CN MXene and its stability in aqueous solutions, ethanol and N , N -dimethylformamide (DMF). Based on the XRD, SEM and TEM results, 20 % HF acid and an etching time of 24 h is regarded as the optimal parameter to synthesize accordion-like Ti 3 CN MXene. Ti 3 CN MXene exhibits limited stability in the aqueous solutions. Ti 3 CN MXene partially transforms to anatase TiO 2 nanoparticles in pH=1 and 7 aqueous solutions, and amorphous TiO 2 nanowires in pH=14 aqueous solution after a 7-day test at 25 °C. When the testing temperature is increased to 80 °C, this structure transformation rate is increased remarkably. Meanwhile, Ti 3 CN MXene shows excellent stability in C 2 H 5 OH and DMF up to 7-day at 25 and 80 °C, respectively. It is believed that these findings are helpful for guiding the controllable synthesis of Ti 3 CN MXene and seeking the potential applications in the presence of aqueous solutions, ethanol and DMF.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Hui Luo,Yunshu Yang,Liwen Lu,Guangxu Li,Xinhua Wang,Xiantun Huang,Xiaoma Tao,Cunke Huang,Zhiqiang Lan,Wenzheng Zhou,Jin Guo,Haizhen Liu
Li–Mg–B–H composite (2LiBH 4 + MgH 2 ) possesses a very high hydrogen storage capacity of 11.4 wt%. However, it still suffers from high operating temperature, slow kinetics, and poor reversibility. In this work, the two-dimensional Ti 3 CN MXene was first synthesized and then introduced into the Li–Mg–B–H composite. The addition of 5 wt% Ti 3 CN reduces the onset dehydrogenation temperature of the 2LiBH 4 + MgH 2 composite by about 50 °C and shortens the induction period of the LiBH 4 decomposition at 400 °C from >90 min to <10 min. The reversible capacity maintains at 8.3 wt% after 20 cycles, with a capacity retention ratio of 93%. Microstructure studies show that Ti 3 CN will partially transform to a highly-dispersed nano-TiB 2 with particle size around 5 nm. Such nano-TiB 2 could serve as an active catalyst to significantly improve the kinetics and reversibility of the Li–Mg–B–H composite. This work offers a strategy to enhancing the hydrogen storage performance of the advanced metal borohydride-based composites by addition of the MXene material and provides some new insights in understanding the role of MXene in tailoring the hydrogen storage properties of the Li–Mg–B–H composite.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2024
·Vol. 14
·期 10
·708
·
IF 3.8
Lei He,Qing Tang,Qi Fan,Haizheng Zhuang,Shengchao Wang,Yifan Pang,Kun Liang
Hydrogen production from water electrolysis is gaining interest as a source of renewable energy storage due to its high efficiency and low environmental impact. However, the slow kinetics of the oxygen evolution reaction (OER) limits the overall efficiency of electrolyzer systems. This study presents the synthesis and characterization of a novel electrocatalyst with a vertical structure, composed of Ti3CN MXene-modified NiFe-layered double hydroxides (LDHs) supported on nickel foam (NF) for efficient OER applications. The 1.0-LDH/3MXNF catalyst exhibits excellent electrocatalytic activity, achieving a low overpotential of 247 mV at a current density of 100 mA cm−2and a favorable Tafel slope of 67.7 mV/dec. This can be attributed to the transfer of excess electrons from Ti3CN MXene to NiFe-LDH, which reduces the oxidation states of Ni and Fe, resulting in a strong interfacial coupling between Ti3CN MXene and NiFe-LDHs. Additionally, the electrode exhibited exceptional stability, maintaining constant performance with minimal potential degradation over prolonged operation. These findings underscore the potential of hybrid LDH-MXene systems as advanced electrocatalysts for renewable energy applications, paving the way for further innovations in energy conversion technologies.
研究领域:
材料科学
·
可再生能源
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2026
·
IF 12.5
Chen Jin,Zhenke Chen,Hang Che,Shuzhong Wang,Zhiheng Liu,Tao Chen,Li Wang,Yuyuan Zhao,Xinhua Wang,Haoyuan Zheng,Haizhen Liu,Mi Yan
Sodium alanate has a reversible hydrogen storage capacity of 5.6 wt% at relatively mild conditions, but it is limited in practical use because of low reaction rates and the phase separation of the reaction product. In this study, to enhance the hydrogen storage ability of sodium alanate, a one-step hydrogen pressure ball milling process was used to introduce the MXene-based carbonitride, Ti 3 CN, and its catalytic modification ability was compared to that of Ti 3 C 2 on sodium alanate. The onset and peak hydrogen desorption temperatures of NaAlH 4 decreased significantly from 176.9 /203.3 °C to 76.8/129.3 °C, and the activation energies for the two-step dehydrogenation process were reduced from 118/159 kJ/mol (pure NaAlH 4 ) to 42/72 kJ/mol. In an isothermal condition at 100 °C, the composite material desorbed 3.30 wt% hydrogen within one hour, and the capacity retention rate kept as high as 93.7% after ten cycles of hydrogen absorption and desorption. It can be obtained that Ti 3 CN maintained its layered structure during the process of ball milling, and there possessed multiple active sites, such as Ti 3 CN, Ti 0 and TiAl. Moreover, TiAl nanointermetallic phases were found to be in situ generated during the cycling process. TiAl displayed a reversible “hydrogen pump” property, acting as nucleation sites to promote the adsorption and desorption of hydrogen. At the same time, the MXene lattice promoted the dispersion of aluminum and the prevention of phase separation. The support stability provided by Ti 3 CN and the coupled catalytic ability of TiAl and Ti 0 phases significantly improved the hydrogen desorption rate and cycling performance of NaAlH 4 at low temperature. These results are valuable to the construction of an efficient solid hydrogen storage system.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Qijun Tang,Peiyao Xiong,Haiqiang Wang,Zhongbiao Wu
Photocatalytic CO 2 reduction to produce value-added products is considered a promising solution to solve the global energy crisis and the greenhouse effect. In this study, Ti 3 CN MXene was synthesized using a Lewis acidic etching method without the usage of toxic hydrofluoric acid (HF). Ti 3 CN MXene was then used as a support for the in situ hydrothermal growth of TiO 2 and Ru nanoparticles. In the presence of 0.5 wt% Ru, Ru-Ti 3 CN-TiO 2 shows CO and CH 4 production rates of 99.58 and 8.97 μmol/g, respectively, in 5 h under Xenon lamp irradiation, more than 20.5 and 9.3 times that of commercial P25. The enhancement in photocatalytic activity was attributed to the synergy between the in-situ growth of TiO 2 on Ti 3 CN MXene and Ru nanoparticles. It was proven experimentally that Ti 3 CN MXene can provide abundant pathways for electron transfer. The separation and transfer of the photo-induced charge were further increased with the help of Ru and Ti 3 CN MXene, leaving more electrons to participate in the subsequent CO 2 reduction reaction. We believe that this work will encourage more attention to designing environment-friendly MXene-based photocatalysts for CO 2 photoreduction using the non-HF method.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）