Materials
·
2022
·Vol. 15
·期 4
·1367
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IF 3.748
Fubing Gui,Yong Huang,Menghan Wu,Xilai Lu,Yongming Hu,Wanping Chen
A high long-term stability is crucial for room-temperature gas-sensitive metal oxide semiconductors (MOSs) to find practical applications. A series of Pd-SnO2mixtures with 2, 5, and 10 wt% Pd separately were prepared from SnO2and Pd powders. Through pressing and sintering, Pd-SnO2composite nanoceramics have been successfully prepared from the mixtures, which show responses of 50, 100, and 60 to 0.04% CO-20% O2-N2at room temperature for samples of 2, 5, and 10 wt% Pd, respectively. The room-temperature CO-sensing characteristics were degraded obviously after dozens of days’ aging for all samples. For samples of 5 wt% Pd, the response to CO was decreased by a factor of 4 after 20 days of aging. Fortunately, some rather mild heat treatments will quite effectively reactivate those aged samples. Heat treatment at 150 °C for 15 min in air tripled the response to CO for a 20 days-aged sample of 5 wt% Pd. It is proposed that the deposition of impurity gases in air on Pd in Pd-SnO2composite nanoceramics has resulted in the observed aging, while their desorption from Pd through mild heat treatments leads to the reactivation. More studies on aging and reactivation of room-temperature gas sensitive MOSs should be conducted to achieve high long-term stability for room-temperature MOS gas sensors.Keywords:CO;sensors;SnO2;aging;heat treatment;recover
研究领域:
材料科学
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传感器技术
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DOI
PubMed
高影响因子
ChemistrySelect
·
2024
·Vol. 9
·期 25
·e202304989
·
IF 1.9
Ying Chen,Zhangyi Lv,Jinqiu Yuan,Mingchun Bi,Yuning Liang
Graphical ZIF-67 nanocubes (ZIF-67 NCs) had been etched to produce small amounts of cross-linked Co-LDH-1 while preserving the cubic structure, which provided sufficient quantities of cobalt ions. The catalytic activity of OER has been enhanced by the cubic-structured LDH, which leads to a significantly lower overpotential in alkaline media and a calculated lower activation energy Ea. To address the substantial energy needs of the quickly evolving modern civilization, efforts are still needed to provide sustainable renewable energy sources. The electrocatalytic Oxygen evolution reaction (OER) is one of the essential technologies used in the various hydrogen production techniques. ZIF-67 nanocubes (ZIF-67 NCs) were synthesized in an aqueous solution and used as sacrificial templates. Cobalt nitrate hexahydrate was added under water bath conditions, resulting in the evolution of numerous small layered layers of cobalt hydroxide. This ultimately led to the formation of multilayered, three-dimensionally crosslinked Co-LDH with a porous networked cubic morphology. Hydrolysis of Co 2+ at different concentrations produces different degrees of weak acidic environments, and the loose LDH on the cubic structure of the best catalyst, Co-LDH-1, exposes more active cobalt sites for the OER, which results in a high electrochemically active surface area, with an overpotential of 354 mV and a Tafel slope of 79.06 mV dec −1 at a current density of 10 mA cm −2 , and good stability and low activation under alkaline condition also has good stability and low activation energy. It provides us an easy and practical plan for logically creating ZIF-derived hydroxide materials, leading to the development of affordable and effective electrocatalysts.
研究领域:
材料科学
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电化学
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能源技术
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DOI
高影响因子
DALTON TRANSACTIONS
·
2025
·
IF 3.3
Xuan Yang,Zesen Yu,Hedong Jiang,Huanhuan Guo,Jian Sun,Jiake Li,Hua Zhu,Yanxiang Wang,Pingchun Guo
Metal–organic frameworks (MOFs) are promising candidates for thermochromic materials. In this study, a hydrogen-bonded 3D porous metal–organic framework, Co-BTC (Co3(BTC)2·12H2O, BTC = 1,3,5-benzenetricarboxylate), exhibited a pink color at room temperature, attributed to the d–d transition of Co2+ ions within the framework, and displayed reversible thermochromic behavior due to alterations in the coordination environment of Co2+ ions. Additionally, Co-BTC/PVB thermochromic film was successfully designed and fabricated as a smart window with a monolayer structure. The window exhibited reversible thermochromic behavior comparable to Co-BTC, with visible transmittance modulation of 10.73%, near-infrared transmittance modulation of 25.87%, and solar transmittance modulation of 12.63%. Compared to a pure PVB window, the smart window reduced indoor temperatures by 5.7 °C in field tests, indicating a significant energy-saving effect. This research presents a potential application for the rational design of MOFs in the development of advanced smart windows.
研究领域:
材料科学
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能源工程
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建筑技术
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DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Yixi Wang,Wenqing Xu,Zhi Liu,Yulong Shan,Wanrong Chen,Xinyu Zhang,Tingyu Zhu
Controlling both CO and NOx pollutants without additional cost is necessary but challenging, especially in industrial flue gas with complex components. Previous studies mainly focused on the effect of O 2 and SO 2 on the CO oxidation side reaction and valence state of Ir species on various catalysts, while neglecting the impact on NO conversion pathway. Herein, we propose an "ineffective reaction pathway" in the presence of O 2 with nitrate as an intermediate according to the results of in situ DRIFTS and DFT. And we also reveal the contribution of SO 2 in inhibiting the adsorption of O 2 and promoting the selective adsorption of NO and CO even at lower injection concentrations, based on the oxidation of SO 2 on Ir(111). This is quite a favorable characteristic for the treatment of industrial flue gas, resolving the long–standing dispute on the involvement of these components in the CO–SCR reaction. Under specific conditions (CO/NO=20, O 2 =5%, SO 2 =200 ppm) at 250 °C, the NOx conversion is as high as 78%. These results will contribute to the development of more efficient catalysts in the future for simultaneously controlling two pollutants (CO and NOx).
研究领域:
环境科学
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催化化学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Xinle Wang,Jin Chen,Yuzhao Ma,Jianye Shi,Yueying Wang,Xiaofeng Yang,Meidan Que,Yuxi Zhou,Yanjun Li
Two-dimensional (2D) transition metal carbide MXene (Ti 3 C 2 T x ) exhibits great potential in electromagnetic wave (EMW) absorbing materials due to its abundant surface functional groups and defects, tunable conductivity and high specific surface area. The Co@NC/TiO 2 /C composites were successfully synthesized through a solvothermal method and carbonization process using Ti 3 C 2 T x /Co-BTC as precursor. The incorporation of magnetic metal Co nanoparticles and Rutile-TiO 2 effectively addresses the issue of single loss mechanism in Ti 3 C 2 T x . The results show that CTC-100 exhibits excellent EMW absorption performance with a minimum reflection loss (RL) value of −51.3 dB at a thickness of only 1.48 mm, and the corresponding effective absorption bandwidth is (EAB, RL < −10 dB) 4.3 GHz. Simultaneously, by adjusting the matching thickness of the material from 1.29 mm to 5.0 mm, the EAB can achieve 15.42 GHz (from 2.85 GHz to 18 GHz). The excellent EMW absorption performance of CTC-100 composite is primarily attributed to the synergistic effect of magnetic loss and dielectric loss. This study provided an effective strategy for the design of Ti 3 C 2 T x -based EMW absorbing materials with high absorption intensity, reduced thickness, and broad effective absorption bandwidth (EAB).
研究领域:
材料科学
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电磁学
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DOI
高影响因子
ChemSusChem
·
2019
·Vol. 12
·期 4
·830-838
·
IF 7.804
Shuai Wang,Haeseong Jang,Jia Wang,Zexing Wu,Xien Liu,Jaephil Cho
Graphical From tannic acid to water splitting : Amorphous Co−P/Co−N−C supported on N, P co-doped porous carbon (Co−P/Co−N−C/NPC) with a large specific surface area and abundant reactive sites is prepared. The material exhibits outstanding catalytic performance for the hydrogen evolution reaction (HER, η =234 mV at 10 mA cm −2 ), oxygen evolution reaction (OER, η =374 mV at 10 mA cm −2 ), and oxygen reduction reaction (ORR, E 1/2 =0.89 V, vs. RHE). It remains a tremendous challenge to develop a low-cost, earth-abundant, and efficient catalyst with multifunctional activities for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR). Herein, a facile and scalable avenue was developed to prepare amorphous Co−P/Co−N−C supported on N, P co-doped porous carbon (Co−P/Co−N−C/NPC) with a large specific surface area (1462.9 m 2 g −1 ) and abundant reactive sites including Co−P, Co−N and NPC. The prepared electrocatalyst exhibits outstanding catalytic performance for HER ( η =234 mV at 10 mA cm −2 ), OER ( η =374 mV at 10 mA cm −2 ), and ORR ( E 1/2 =0.89 V, vs. reversible hydrogen electrode). Benefiting from the excellent HER performance and outstanding OER activity, the Co−P/Co−N−C/NPC delivers a current density of 10 mA cm −2 for overall water splitting at a cell voltage of 1.59 V, which is comparable with the IrO 2 –Pt/C couple electrode.
研究领域:
材料科学
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电化学
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催化
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能源材料
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DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2024
·
IF 3.7
Huijun Shang,Hengli Li,Weijun Li,Feng Pan,Zhan Du
In this paper, the effects of reaction parameters on the deep-reduction and carbonization process of WO 2 -Co to WC-Co were studied. The results indicate that oxygen loss rate of WO 2 is positively correlated with temperature and methane partial pressure. The partial pressure of methane has no significant effect on the formation rate of WC. The carbon content and particle size of the product increase with the increase of CH 4 partial pressure. By synergistically regulating the reaction temperature to 950 °C, methane partial pressure to 1.25%, and reaction time to 60 min, ultrafine WC-Co powder without η phase can be obtained. The particle size of the composite powder is 128 nm, with total carbon content of 6.16%, free carbon content of 0.4%, and residual oxygen content of 0.05%, respectively. The growth rate relationship of tungsten carbide is as follows:
研究领域:
材料科学
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化学工程
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DOI
高影响因子
Biosensors-Basel
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2024
·Vol. 14
·期 12
·586
·
IF 4.9
Xiaowei Fan,Guping Zhang,Xiaodi Li,Yao Wang,Yi Wang,Shilei Hao,Defang Liu
In this study, we have proposed an electrochemiluminescence (ECL) signal amplification system which is based on two-dimensional (2D) flower-like CdS@Co/Mo-MOF composites as a co-reaction accelerator of the g-C3N4/S2O82−system for ultrasensitive detection of chlorpromazine hydrochloride (CPH). Specifically, the 2D flower-like Co/Mo-MOF with mesoporous alleviated the aggregation of CdS NPs while simultaneously fostering reactant-active site contact and improving the reactant–product transport rate. This allowed the material to act as a novel co-reaction accelerator, speeding up the transformation of the S2O82−into SO4•−and enhancing the cathodic ECL emission of g-C3N4. Moreover, the signal probe which was synthesized by coupling the 2D CdS@Co/Mo-MOF and graphitic carbon nitride (g-C3N4) achieved the generation of SO4•−in situ and reduced energy loss. The results confirmed that the ECL signal was enhanced 6.2-fold and stabilized by CdS@Co/Mo-MOF. Based on the extremely strong quenching effect of chlorpromazine hydrochloride (CPH) on this system, a “signal-off” type sensor was constructed. The sensor demonstrated excellent sensitivity and linear response to CPH concentrations ranging from 1 pmol L−1to 100 μmol L−1, with a low detection limit of 0.4 pmol L−1(S/N = 3).
研究领域:
材料科学
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分析化学
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医学检测
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DOI
PubMed
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2018
·Vol. 86
·期 3
·699-710
·
IF 1.745
Guo Jiuli,Han Qiuwan,Zhong Siyuan,Zhu Baolin,Huang Weiping,Zhang Shoumin
The M-modified TiO 2 nanotubes (NTs) (M = Ce, Ga, Co, Y, 2.0 wt%) were synthesized by combining sol-gel method with hydrothermal treatment, based on which gold was loaded by the deposition–precipitation approach. These catalysts were loaded with 1.5 wt% gold and calcined at 300 °C, and their catalytic performance was compared with Au/TiO 2 NTs in CO oxidation. TEM results manifested Au/M-TiO 2 NTs (M = Ce, Ga, Co, Y) had smaller gold nanoparticles than Au/TiO 2 NTs. Patterns of XPS revealed the presence of the strong interaction between gold and support in Au/M-TiO 2 NTs (M = Ce, Ga, Co, Y). Ce 4+ , Ga 3+ , Co 2+ , and Y 3+ ions were present as CeO 2 , Ga 2 O 3 , CoO, and Y 2 O 3 in Au/M-TiO 2 NTs (M = Ce, Ga, Co, Y), respectively. Based on O 2 -TPD studies, Au/M-TiO 2 NTs (M = Ce, Ga, Co, Y) provided new O 2 adsorption sites for the adsorption and activation of oxygen in CO oxidation. M (M = Ce, Ga, Co, Y) modifying performed the positive effect on CO oxidation activity and Au/Y-TiO 2 NTs showed the highest activity among these catalysts. Additionally, Au/Y-TiO 2 NTs also performed excellent high-temperature stability. It was likely that the strong interaction between gold and support created the small size of gold nanoparticles, large O 2 adsorption and plenty of defects, thereby enhancing the catalytic activity of Au/M-TiO 2 NTs (M = Ce, Ga, Co, Y).
研究领域:
材料科学
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催化化学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Yuxi Meng,Shaomian Liu,Yixi Wang,Wenqing Xu,Jiajian Gao,Sansan Yu,Fabing Su,Tingyu Zhu
Selective catalytic reduction of NO using CO (CO-SCR) is a promising technology for the purification of NO in the flue gas. However, the presence of O 2 significantly inhibits the activity of the CO-SCR catalyst. Herein, we synthesize a hollow Mn-doped CeO 2 @Co 3 O 4 catalyst (Mn-CeO 2 @Co 3 O 4 ), which achieved 82% NO conversion, 100% CO conversion, and 78% N 2 selectivity under 5 vol% O 2 at 200 °C, superior to those of CeO 2 @Co 3 O 4 and Co 3 O 4 @CeO 2 catalysts. The characterization results indicate that the strong electronic interaction at the heterointerfaces between Co 3 O 4 and CeO 2 plays a crucial role in promoting selective adsorption of NO. Furthermore, the Mn doping into the Co 3 O 4 lattice of the catalyst facilitates the conversion of N 2 O intermediates, thereby enhancing the overall activity. This research provides a new strategy for the design and synthesis of CO-SCR catalysts.
研究领域:
催化
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环境科学
·
材料科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zhu-yu Li,Le-ran Li,Sheng Li,Ding-can Wang,Qi Niu,Kai Li,Ji Liu,Qiang Lu
Calcium-based thermochemical heat storage (TCHS) is an economical and environmentally friendly technology for efficient heat storage. It can strengthen the flexibility in power systems of renewable energy and promote the recovery and storage of waste heat in energy-intensive industries. However, CaO/CaCO 3 is extremely prone to sintering at operational temperatures. Consequently, a cost-effective approach was proposed to synthesize calcium-based TCHS materials modified by pyroligneous acid (PA) impregnation and co-doping with dual transition metals. The heat storage performance, physicochemical property, and anti-sintering mechanism of synthesized CaO were comparatively examined. The sample prepared with a molar ratio of Ca: Co: Mn = 100:3:7 (PACa-Co3Mn7) exhibited an initial energy storage density of 1.76 MJ/kg, which gradually rose to 1.88 MJ/kg. After 20 cycles, the value decreased by only 4.39 % from its peak, indicating outstanding TCHS performance. Characterization results indicated that the specific surface area and pore volume of PACa-Co3Mn7 were 10.48 m 2 /g and 0.035 cm 3 /g, which were 2.34 and 2.69 times those of CaO stemmed from the calcination of limestone, respectively. The fruitful pores provided pathways for CO 2 diffusion within the CaO particles or CaCO 3 product layer. The uniformly distributed Co and Mn elements combined to form Ca 3 CoMnO 6 . Ca 3 CoMnO 6 could serve as the inert carrier that mitigated the grain-growth of CaO, thereby stabilizing the pore structure and resisting the sintering of PACa-Co3Mn7. Furthermore, density functional theory (DFT) calculations demonstrated that the free Mn and Co elements efficiently promoted the electrons transfer between CaO and CO 2 , which improved the reactivity of PACa-Co3Mn7. Therefore, CaO modified by PA impregnation and co-doping with dual transition metal is a promising candidate for the TCHS system.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2015
·
IF 4.772
Yuangang Li,Rongrong Wang,Huajing Li,Xiaoliang Wei,Juan Feng,Kaiqiang Liu,Yongqiang Dang,Anning Zhou
Co-Pi decorated TiO2@graphitic carbon nitrides (g-C3N4) nanorod arrays (denoted as CCNRs) with different mass ratios of g-C3N4 have been constructed on the FTO substrate through three processes, hydrothermal growth, chemical bath deposition and electrodeposition. First, TiO2 nanorod arrays were grown onto a FTO substrate by a hydrothermal method. Second, g-C3N4 was coated onto the TiO2 nanorod arrays by immersing the above substrate with TiO2 nanorod arrays into a solution of urea and then heated at higher temperature. In this procedure, the amount of the g-C3N4 on the TiO2 nanorod arrays can be controlled by tuning the concentration of the urea solution. At last, Co-Pi were decorated on the surface of the TiO2@g-C3N4 by electrodeposition. The as-prepared CCNRs were characterized by XRD, FESEM, TEM, XPS, UV–vis, and FTIR, respectively, which illustrated that Co-Pi moieties were successfully decorated on the hybrid TiO2@g-C3N4 nanorod arrays. Photoelectrochemical (PEC) measurements have demonstrated that the prepared CCNRs serve as an efficient and stable photoanode for PEC seawater splitting. The photocurrent density reaches 1.6 mA/cm2 under 100 mW/cm2 (AM1.5G) light illumination at 1.23 V (RHE). More significantly, the CCNRs photoanode is quite stable during seawater splitting and the performance remain undiminished even after 10 h continuous illumination. Finally, a systematical photocatalytic mechanism of the Co-Pi decorated TiO2@g-C3N4 was proposed, and it can be considered as potential explanation of enhanced PEC performance.
研究领域:
材料科学
·
化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）