Sustainability
·
2022
·Vol. 14
·期 20
·13417
·
IF 3.889
Pingshu Leng,Hanbin Wang,Binfeng Wu,Lei Zhao,Yijing Deng,Jinting Cui,Houzhao Wan,Lin Lv
The use of transition metals as bifunctional catalysts for rechargeable zinc-air batteries has recently attracted much attention. Due to their multiple chemical valence states, the cobalt oxides are considered to be promising catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In this work, bifunctional Ag-decorated Co3O4-nitrogen doped porous carbon composite (Co3O4-NC&Ag) catalysts were synthesized by annealing ZIF-67 in N2and O2, respectively, followed by Ag deposition using chemical bath deposition. Due to the decoration of Ag nanoparticles and high specific surface area (46.9 m2g−1), the electrochemical activity of Co3O4increased significantly. The optimized Co3O4-NC&Ag catalysts possessed superior ORR performance with a half-wave potential of 0.84 V (vs. RHE) and OER activity with an overpotential of 349 mV at 10 mA cm−2. The open circuit voltage of the Co3O4-NC&Ag-based zinc-air battery was 1.423 V. Meanwhile, the power density reached 198 mW cm−2with a specific discharge capacity of 770 mAh g−1at 10 mA cm−2, which was higher than that of Pt/C-based zinc-air battery (160 mW cm−2and 705 mAh g−1). At a current density of 10 mA cm−2, the charge-discharge performance was stable for 120 h (360 cycles), exhibiting better long-term stability than the Pt/C&RuO2counterpart.Keywords:zinc air battery;Co3O4;bifunctional catalysts;silver decoration
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
FUEL
·
2021
·
IF 6.609
Guang Miao,Peng Chong,Cuiting Yang,Zewei Liu,Hao Yu,Lei Dong,Guoqing Li,Jing Xiao
The demand for heterocyclic sulfur compounds is increasingly in fine chemical industry, where the thiophenic sulfur impurities in fuels can be a potential recyclable feedstock. In this work, the catalytic upgrading of thiophenic sulfur compounds over a silver-modified MoO 3 catalyst under ambient conditions was reported. Br 2 and H 2 O 2 /HBr were used to convert thiophenic compounds in alkane and alcohol solutions. The conversion of various thiophenic compounds (thiophene, benzothiophene and dibenzothiophene) to the corresponding bromides reached up to 81.6 ~ 99.8%. The bromination path undergoes electrophilic substitution mechanism, and the transformation of mono- to dibromides is identified as the rate-determining step. The introduction of MoAg 2 O 4 phase on MoO 3 is rationalized to boost the conversion of mono-bromothiophene, which results in the selectivity of 2,5-dibromothiophene increased from 10% to over 50%. The optimized silver loading was 10% due to its high thiophene conversion and selectivity of dibromides. Silver modification of MoO 3 rods not only stabilized the textural property of catalysts but also improved its bromination activity compared to the bulk MoO 3 indicated by SEM and FTIR characterization. Density functional theory (DFT) calculation suggested that the formation of 2-bromothiphene and 2,5-dibromothiophene were preferred on the MoO 3 (111) and MoAg 2 O 4 (111) sites, respectively. The catalytic upgrading approach paves the way for the efficient utilization of thiophenic sulfur impurities in fuels to their value-added under mild conditions.
研究领域:
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2025
·
IF 6.3
Jiaqi Li,Ziming Shang,Ying Meng,Qianrui Lv,Fubo Luan
TiO 2 -based photocatalytic nitrate reduction is highly efficient for nitrate treatment. However, TiO 2 powders present challenges in recovery and reuse, necessitating immobilization to enhance recyclability. Additionally, existing research primarily focuses on the role of photogenerated electrons in nitrate removal, neglecting the impact of simultaneously generated free radicals on the reaction. To investigate the synergistic effects of electrons and free radicals in recyclable photocatalytic nitrate reduction, this study layered TiO 2 with specific crystal facets and a silver coating on a recyclable plane. Results indicate that hydroxyl radicals (·OH) can reoxidize ammonia nitrogen, inhibiting the interfacial reduction process and adversely affecting nitrate removal. Exposing the reductive (101) crystal facet and depositing silver nanoparticles helps promote electron migration to the nanoparticle surface for participation in the reduction process, while reducing free radical formation. This approach increases the nitrate degradation rate by 2.38 times compared to TiO 2 with the exposed (001) crystal facet. In contrast, the photocatalytic reduction efficiency of TiO 2 with exposed oxidative (001) crystal facet is reduced due to increased free radical formation influenced by surface positive charges. This study provides a cost-effective and reusable solution for nitrate removal in water, enhancing its potential in practical water treatment applications.
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
Catalysts
·
2024
·Vol. 14
·期 2
·135
·
IF 3.8
Baofang Jin,Yuxin Liu,Yue Ma,Zhenguo Li,Kaixiang Li,Shuang Liu,Rui Ran,Xiaodong Wu
A series of Ag-modified manganese-mullite (SmMn2O5) catalysts with different Ag contents (1, 3, and 6 wt.%) were prepared via a citric acid sol–gel method for catalytic soot oxidation. The catalysts were characterized by powder X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Raman spectroscopy, transmission electron microscopy (TEM), high-resolution transmission electron microscopy analysis (HRTEM), X-ray photoelectron spectroscopy (XPS), and H2temperature-programmed reduction (H2-TPR). The soot oxidation activity of the mullite was significantly promoted by the addition of silver and affected by the loading amount of the metal. Herein, the influences of silver loading on the metal size distribution and its interactions with the mullite were studied. Based on these characterizations, a possible soot oxidation reaction mechanism was proposed for silver-modified SmMn2O5.
研究领域:
催化材料
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2021
·Vol. 28
·期 28
·37592-37602
·
IF 4.223
Li Tao,Zhao Jinxian,Quan Yanhong,Luo Dongmou,Miao Chao,Ren Jun
Co 3 O 4 nanorods with diameters of ~0.15 μm and lengths of ~1 μm were prepared using a hydrothermal method via the assembly of microcrystals and tested in the catalytic oxidation of toluene. The catalytic performance of Co 3 O 4 nanorods was improved by the addition of Ag at various concentrations, and the 7% Ag/Co 3 O 4 catalyst achieves a toluene conversion of 90% at 256 °C with a space velocity of 78,000 mL g −1 h −1 , which is much lower than that of the pristine Co 3 O 4 (269 °C). The addition of Ag promoted the activation of the surface oxygen species and the formation of more oxygen vacancies, improving the relative low-temperature reducibility of Co 3 O 4 , which is favorable for toluene oxidation. Moreover, the 7% Ag/Co 3 O 4 catalyst showed an excellent stability for toluene oxidation at 250 and 260 °C for 50 h under the same conditions.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2024
·Vol. 14
·期 10
·848
·
IF 4.4
Jun Wu,Gaofeng Shao,Xiaodong Wu,Sheng Cui,Xiaodong Shen
A novel Cr-doped BaTiO3aerogel was successfully synthesized using a co-gelation technique that involves two metallic alkoxides and a supercritical drying method. This freshly prepared aerogel has a high specific surface area of over 100 m2/g and exhibits improved responsiveness to the simulated sunlight spectrum. Methyl orange (MO) was chosen as the simulated pollutant, and the results reveal that the Cr-doped BaTiO3aerogel, when modified with the noble metal silver (Ag), achieves a pollutant removal rate approximately 3.2 times higher than that of the commercially available P25, reaching up to 92% within 60 min. The excellent photocatalytic performance of the Ag-modified Cr-doped BaTiO3aerogel can be primarily attributed to its extensive specific surface area and three-dimensional porous architecture. Furthermore, the incorporation of Ag nanoparticles effectively suppresses the recombination of photo-generated electrons and holes. Stability and reusability tests have confirmed the reliability of the Ag-modified Cr-doped BaTiO3aerogel. Therefore, this material emerges as a highly promising candidate for the treatment of textile wastewater.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Surfaces and Interfaces
·
2025
·
IF 6.3
Lujie Ruan,Honglin Zhou,Xiangyu Li,Yuxuan Wang,Pengfei Luo,Haixuan Wang,Jiangping Ma,Chaogang Ban,Xiaoxing Wang,Jiangjie Ye,Yajie Feng,Jili Yue,Li-Yong Gan,Xiaoyuan Zhou,Ji-Yan Dai
Addressing the growing demand for clean energy necessitates innovative approaches to enhance hydrogen production efficiency. Combining photo-catalysis and piezo-catalysis offers a synergistic strategy for energy conversion, yet the limited charge transfer and separation efficiency in pure Bi 2 WO 6 hinders its catalytic performance. Herein, by adopting Ag nanoparticles deposited on Bi 2 WO 6 nanosheets (Bi 2 WO 6 –2% Ag) as a paradigm, it is demonstrated that the incorporation of Ag significantly enhances charge separation and transfer via improved piezoelectric and electronic interactions. This modification not only boosts the piezoelectric coefficient by 1.78-fold but also promotes the generation of piezo-induced and photogenerated carriers. Consequently, Bi 2 WO 6 –2% Ag achieves a hydrogen yield of 14.3 mmol·g -1 ·h -1 under piezo-catalytic conditions, a 60.7% improvement compared to pristine Bi 2 WO 6 . Under combined piezo-photo-catalytic conditions, the hydrogen yield further increases to 30.9 mmol·g -1 ·h -1 . The enhanced performance is attributed to the synergistic effects of ultrasonic vibration and ultraviolet light, which induce band bending and polarization-driven charge migration, facilitating hydrogen production. This study provides valuable insights into the integration of noble metal deposition and piezo-photo-catalysis, opening a new pathway for the design of advanced catalysts for sustainable hydrogen energy solutions.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 55
·期 2
·701-712
·
IF 3.442
Yang Wangyang,Shen Honglie,Min Huihua,Ge Jiawei
In recent years, Ti 3+ self-doped TiO 2 (B-TiO 2 ) exhibits great potential as a photocatalyst. In this work, Ti vapor-assisted annealing is first demonstrated for Ti 3+ doping and improving the visible absorption of TiO 2 . TEM results exhibit the formation of disordered layer, indicating the successful fabricating of B-TiO 2 . The absorption increase in TiO 2 caused by Ti vapor annealing reaches nearly 50% in the visible wavelength range. Benefiting from the absorption increase, the photocatalytic performance of TiO 2 after Ti vapor annealing increases by 60–70%. Surface modification of Ag onto B-TiO 2 is also carried out to further improve its optical property. Ag-modified Ti 3+ self-doped TiO 2 (B-TiO 2 @Ag) exhibits great visible photodegradation behavior to RhB. The RhB degradation rate reaches 97.76% after 60 min of visible light irradiation. Electrochemical performance tests demonstrate that as-prepared TiO 2 @Ag has lower resistance than W-TiO 2 . The results indicate that B-TiO 2 @Ag has great potential in solar photocatalytic degradation of pollutant.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Cheng Luo,Dazhuang Fei,Jintang Zhou,Jiaqi Tao,Zhengjun Yao,Jun Liu,Yansong Gu,Xuewei Tao
Composite materials with good thermal conductivity and wave-absorbing ability are an important innovation in the multifunctionalization of current wave-absorbing materials. However, how to make wave-absorbing materials with high thermal conductivity, is still a difficult problem to overcome in the field of electromagnetic wave absorption (EWA). In this paper, boron nitride nanosheets were modified by surface polymerization of phenolic aldehyde, and the impedance matching properties of the materials were optimized by trace silver modification, after which they were annealed at 700 °C and blended with silicone rubber. The results made clear, that it achieves excellent absorption bandwidth (6.89 GHz) at a lower thickness (2.3 mm), while the thermal conductivity of the composite reaches 0.42 W/(m•k) at this performance of the filler ratio, which is a 210% enhancement compared to the thermal conductivity of pure silicone rubber [0.2 W/(m•k)], and is only 0.02 W/(m•k) lower than pure BN composites at the same filling ratio. This shows that the prepared material not only has good microwave absorption ability, but also has excellent thermal conductivity. The material is simple to make. It has a high industrialization potential and can serve as a powerful guide for the development of ceramic materials into heat-conducting and wave-absorbing materials in the future.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale Advances
·
2024
·Vol. 6
·期 20
·5133-5144
·
IF 4.6
Nada Gamal ElSayed,Ahmed A. Farghali,Waleed M. A. El Rouby,Mai F. M. Hmamm
The higher energy density and lesser toxicity of ethanol compared to methanol make it an ideal combustible renewable energy source in fuel cells. Finding suitable cost-effective electrocatalysts that can oxidize ethanol in ethanol-based fuel cells is a major challenge. With their high catalytic activity and stability in alkaline media, transition metal-based catalysts are ideal candidates for alkaline direct ethanol fuel cells. Nickel-based nanomaterials and composites exhibit high electrocatalytic activity, which makes them predominant candidates for the electrochemical oxidation of ethanol. In this study, the electrocatalytic activity of a nickel oxide flower-like structure was explored. Forming a nanocomposite of NiO in combination with carbon nanotubes (CNTs), NiO/CNTs, as a substrate led to an increase in the stability of the electrocatalyst in alkaline media. Furthermore, the electrocatalytic activity of the NiO/CNT nanocomposite was greatly enhanced by decorating the surface with different ratios of silver (Ag). Ag/NiO/CNT composites with different Ag ratios, namely, 25% and 50% by weight, were studied. The Ag 25%/NiO/CNT weight ratio showed a maximum ethanol conversion. At an ethanol concentration of 300 mM, the electrochemical oxidation current density was found to be 57.1 ± 0.2 mA cm−2 for the 25% by weight Ag ratio, with a five-fold increase in the current density (compared to NiO/CNTs (10 ± 0.34 mA cm−2)). Furthermore, the nanocomposite synthesized here (Ag 25%/NiO/CNTs) showed a significantly higher energy conversion (current per ethanol concentration) rate compared to other reported NiO-based catalysts. These results open real opportunities for designing high efficiency ethanol fuel cell catalysts.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Baofang Jin,Baohuai Zhao,Shuang Liu,Zhenguo Li,Kaixiang Li,Rui Ran,Zhichun Si,Duan Weng,Wu Xiaodong
The mullite SmMn 2 O 5 (SMO) was modified with silver for soot oxidation by two methods, i.e. sol-gel (Ag/SMO-sg) and impregnation (Ag/SMO-im). The catalysts were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma atomic emission spectrometry (ICP-AES), H 2 -O 2 titration, H 2 temperature-programmed reduction (H 2 -TPR), CO temperature-programmed reduction (CO-TPR), soot temperature-programmed reduction (soot-TPR), O 2 temperature-programmed desorption (O 2 -TPD), cycled H 2 temperature-programmed reduction (cycled H 2 -TPR), NO temperature-programmed oxidation (NO-TPO) and soot temperature-programmed oxidation (soot-TPO). Metallic silver nanoparticles were observed in the mullite matrix for both the catalysts. For Ag/SMO-sg, the possible incorporation of silver into the mullite crystal cell and strong electronic interaction between the highly dispersed metal and the support increase the Mn 4+ /Mn 3+ ratio and create more structural defects in the mullite, resulting in boosted NO oxidation and thereby NO 2 -assisted soot combustion. The introduction of Ag can promote the generation/regeneration of active oxygen, which accelerates the ignition of soot in O 2 at low temperatures. Therefore, the sol-gel-synthesized Ag/SmMn 2 O 5 is highly promising for application in diesel particulate filters.
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Weiwei Meng,Ling Wang,Yuehua Li,Lei Dai,Jing Zhu,Huizhu Zhou,Zhangxing He
Bi 0.95 Ni 0.05 VO 3.975 with flower-like structure was prepared by the hydrothermal method. Mixed potential type NH 3 sensors were fabricated using Bi 0.95 Ni 0.05 VO 3.975 as sensing electrode and La 10 Si 5.5 Al 0.5 O 27 as electrolyte. The sensing performance of the sensors was tested in the temperature range of 500–650 °C. The test results show that the sensor exhibits excellent NH 3 sensing performance. The response signals linearly depend on the logarithm of the NH 3 concentrations. The sensor also shows a good stability and reproducibility. The sensor displays a good anti-interference ability to CO 2 , H 2 and CH 4 . However, NO 2 leads to a great influence on the response potential of the sensor. The effect of introduction of Ag into sensing electrode on sensor performances was investigated. Compared with the sensor based on Bi 0.95 Ni 0.05 VO 3.975 , the sensor with the Ag modified Bi 0.95 Ni 0.05 VO 3.975 sensing electrode shows much higher sensitivities. More importantly, the interference from NO 2 is completely eliminated and the selectivity of the sensor is significantly improved, which can be attributed to the NO 2 adsorption ability of the sensing material being depressed by the introduction of Ag. This strategy provides a new idea to improve the selectivity of NH 3 sensor besides sensitivity.
研究领域:
材料科学
·
传感技术
✓ 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）