SEPARATION SCIENCE AND TECHNOLOGY
·
2018
·
IF 1.2
Yan Yan,Qi Wang,Zeyang Xiang,Yanzhao Yang
A reasonable project was presented for the extraction and separation of Pt(IV), Pd(II), Ru(III), and Rh(III) from the mixed imidazolium-based ionic liquids (ILs) [C6mim]Cl, [C6mim][NTf2], and [C6mim][DDTC]. Pt(IV) was first separated from other three platinum group metals with a mixture of [C6mim]Cl and [C6mim][NTf2]. Then, separation of Pd(II) and Ru(III) from Rh(III) was realized by changing the concentration of [C6mim][DDTC]. Back-extraction of Pt(IV), Pd(II), and Ru(III) from loaded hydrophobic phase and the recovery of Rh(III) in aqueous phase were also investigated. Mechanisms between Pd(II)/Ru(III) and [C6mim][DDTC] were further explored using ultraviolet spectrophotometry (UV-Vis), infrared spectrophotometry (FTIR), the method of continuous variations, ab initio quantum chemical studies, and X-ray crystallographic analysis. The results afford more directions for extracting and separating metals by introducing devisable functionalized group into ILs.
研究领域:
化学工程
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2025
·Vol. 17
·期 7
·857
·
IF 4.9
Bolun Li,Mengyan Wang,Huixiang Luo,Kaina Li,Yanlong Jia,Mingjie Fu,Chenyu Jiang,Shuangquan Yao,Yongjun Yin
As a carbon-neutral and renewable raw material, cellulose can be transformed into biomass fuels to reduce the dependence on fossil fuels and carbon dioxide emissions. In view of harsh reaction conditions, low selectivity of product, and easy deactivation of the catalyst, this study studied the use of photothermal catalytic technology to convert cellulose into bio-oil rich in levulinic acid. It was discovered that a synergistic effect between heating and photocatalysis is present in cellulose degradation. Different metals were loaded on carbon nanotubes doped with titanium dioxide to prepare different photothermal catalysts, and their catalytic effects on cellulose were compared. It was found that TiO2-CNT loaded with platinum metal exhibited the highest catalytic performance. By adopting Pt/TiO2-CNT as the catalyst, the conversion rate of bio-oil reached 99.44%, and the selectivity of LA reached 44.41% at 220 °C for 3 h. As the photothermal catalysis increased the H/C ratio and decreased the O/C ratio of the liquid product, the calorific value reached 21.01 MJ/kg. This study can promote the further industrial application of lignocellulose to prepare fuel oil and decrease the environmental pollution caused by the massive consumption of fossil fuels.
研究领域:
能源科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 55
·期 26
·11829-11840
·
IF 3.553
Xie Wenwen,Huang Zeai,Wang Ruiqi,Wen Cheng,Zhou Ying
Photocatalytic production of green oxidation reagents as an economical and environmental-friendly process is a promising strategy to replace the traditional production processes. In the present study, a series of 1.0 wt% Pt/WO 3 photocatalysts with different surface chemical states of Pt were successfully fabricated. The different surface metallic Pt (Pt 0 ) and oxidized Pt (PtO x ) ratios on WO 3 showed significant effects on the photocatalytic activities for strong oxidants of peroxydisulfate ( \( {\text{S}}_{ 2} {\text{O}}_{8}^{2 - } \) ) and hydrogen peroxide (H 2 O 2 ) formations. It is proposed that surface Pt 0 and PtO x functioned as reduction site for O 2 reduction to H 2 O and oxidation site for H 2 O oxidation to H 2 O 2 , respectively, during the photocatalytic process. As a result, a higher surface composition of Pt 0 prepared using photodeposition (PD) method led to the formation of higher amount of \( {\text{S}}_{ 2} {\text{O}}_{8}^{2 - } \) . On the other hand, PtO x -loaded WO 3 using impregnation (IM) method showed significant formations of \( {\text{S}}_{ 2} {\text{O}}_{8}^{2 - } \) and H 2 O 2 simultaneously. This work provided a new idea for the design of noble metal Pt-supported WO 3 for efficiently photocatalytic generation of \( {\text{S}}_{ 2} {\text{O}}_{8}^{2 - } \) and H 2 O 2 .
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
ChemCatChem
·
2020
·Vol. 12
·期 9
·2469-2477
·
IF 4.853
Lidong Wang,Zhaosheng Zhang,Meng Li,Qiuhan Li,Bo Wang,Shuwen Wang,Huang Zhou,Boyang Mao
Graphical HER electrocatalysis : We developed a novel Pt(II)-porphyrin based catalyst for HER electrocatalysis, its optimised performance can be quantitatively designed in molecular level. The optimized Pt(II)-porphyrin loading and precisely morphology control could be fine-tuned and quantitatively premeditated by using fluorescence and UV-vis titration based on the unique π–π interactions behaviour of the porphyrin. This study provides a new approach for preparing a highly active and stable HER catalyst, which could potentially be extended to other reactions to improve the utilization efficiency of precious metal catalysts. Functionalised porphyrins have attracted considerable attention owing to their ability to coordinate with numerous metal ions. We design and synthesize a novel composite system based on functionalised Pt(II)-porphyrin and multiwalled carbon nanotubes for hydrogen evolution reaction (HER) electrocatalysis. Rather than qualitatively integrating porphyrin with carbon nanotubes, the optimized Pt(II)-porphyrin loading and precisely morphology control could be fine-tuned and quantitatively premeditated by using fluorescence and UV-vis titration based on the unique π–π interactions behaviour of the porphyrin for the first time. The as-prepared composites exhibit superior HER catalytic activity with an overpotential of 35 mV for an electrocatalytic current density of j=−10 mA cm −2 and a Tafel slope of 32.3 mV dec −1 . Moreover, such catalysts do not exhibit observable activity decay after a 1000-cycle stability test, thus demonstrating their excellent durability. To further reduce Pt loading to achieve cost efficiency, we develop a Pt−Co bimetallic HER catalyst with an ultra-low platinum content through a straightforward synthesis pathway with high catalytic activity and stability. This study provides a new approach for preparing a highly active and stable HER catalyst, which could potentially be extended to other reactions to improve the utilization efficiency of precious metal catalysts.
研究领域:
材料科学
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化学工程
·
能源科学
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产品关联
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2017
·Vol. 20
·期 4
·2205-2210
·
IF 4.123
Rui-Ling Zhang,Yang Yang,Song-Qiu Yang,Ke-Li Han
Host–guest charge transfer (HGCT) plays a key role in applications from solar energy conversion to photocatalysis. Herein, a HGCT system, a pillared Pt(II) metallacage with encapsulated coronene was synthesized and the ultrafast excited-state dynamics were investigated by combination of femtosecond transient absorption spectroscopy, nanosecond transient emission spectrocopy and quantum chemistry calculations. Two significant ultrafast dynamic processes were unveiled: (i) charge transfer from a singlet local excited (1LE) state associated with the coronene moiety to a 1HGCT state with τ = 9.5 ps; and (ii) triplet–triplet energy transfer from a high 3HGCT state to a 3LE state with τ = 139.5 ps. The resulting long-lived species, the lowest 3LE and 3HGCT states eventually decay to the ground state in microsecond time scales of 5.2 and 43.4 μs respectively. Moreover, a clear mechanism depicting the main excited-state decay pathways connecting the initial photoexcited transients with the resulting species was proposed.
研究领域:
化学
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光化学
·
理论计算
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL PHYSICS
·
2024
·
IF 2
Lu Li,Feng Qin,Yongda Wang,Zhiguo Zhang
The proportion of singlet oxygen ( R ) produced from the triplet state of porphyrin in aqueous solutions was investigated by substituting porphyrin molecules with the metalloporphyrin Platinum(II) meso -tetraphenylporphyrin (Pt-TPP). The feasibility of using platinum porphyrin as a substitute for porphyrin to study the photophysical properties in photodynamic therapy (PDT) was confirmed. The model of first-order decay in a water-methanol mixed solution encompasses potential deactivation processes of the excited triplet states and was built, which was confirmed by monitoring the change in the total transition rate of the T 1 state ( A 0 ) value at different water contents under anoxic environments, obtained through measuring the phosphorescence lifetime ( τ p ) of Pt-TPP. Combined with A 0 and the quenching rate constant of T 1 by O 2 ( k q ), the formula for R in relation to changes in oxygen can be deduced in pure water.
研究领域:
生物化学
·
医学
✓ 已验证
产品关联
DOI
高影响因子
Applied Catalysis O: Open
·
2024
·
IF 0
Ya-Song Lin,Hui-Zi Han,Xiao-Qi He,Xian-Tai Zhou
A highly efficient and selective protocol for the oxidation of alkyl aromatics with tert -butyl hydroperoxide (TBHP) oxidant over platinum meso -tetraphenylporphyrin (Pt( II )TPP) was developed. Various alkyl aromatics were selectively converted to ketones smoothly with yields higher than 90% under the optimized conditions. Kinetic studies revealed that the oxidation was first-order with respect to the substrate, and the activation energy ( E a ) was 50.8 kJ mol −1 . Moreover, a mechanism involving high-valence platinum species and free radicals was proposed.
研究领域:
有机化学
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催化化学
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物理化学
✓ 已验证
DOI
ENVIRONMENTAL RESEARCH
·
2025
·
IF 7.7
Lina Xiao,Qiuping Zhang,Xinzhi Wang,Huan Zhang,Wenxuan Li,Hao Zhang,Bowen Li
Efficient solar energy storage via light-driven hydrogen (H 2 ) production presents a promising and attractive strategy for addressing the global energy crisis. The integration of platinum (Pt) co-catalyst into metal-organic frameworks (MOFs) to enhance photoinduced charge separation and transfer remains a significant challenge. Herein, a platinum–porphyrin zirconium metal-organic framework (MOF) PCN-223(Pt) is reported, and synthesized using a facile two-solvent strategy. The prepared PCN-223(Pt) is self-sensitized and contains a platinum (Pt) electron-trapping center, which confers excellent visible-light catalytic activity. Under visible-light irradiation, PCN-223(Pt) produced 732 μmol g −1 h −1 of H 2 , a 7.6-fold increase compared to the isostructural PCN-223, which lacks Pt coordination in its porphyrin rings. This improvement results from the photogenerated electrons' efficient transport to the Pt electron-trapping centers, which improves charge carrier separation. Density functional theory calculations demonstrate the positive role that Pt in PCN-223(Pt) play in optimizing the corresponding hydrogen binding energy. PCN-223(Pt) exhibits excellent recyclability, maintaining its catalytic performance across five cycles without significant degradation. These results offer a new approach for designing MOF-based highly efficient visible-light active catalysts.
研究领域:
材料科学
·
能源化学
·
催化科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CATALYSIS TODAY
·
2018
·
IF 4.667
Xiao Dong,Peng Zheng,Ai-Guo Zheng,Hui-Feng Li,Guo-Fu Xia,Ming-Feng Li,Ren-Yang Zheng,Bo-Qing Xu
Pt-Co/SiO 2 and Pt-Ir-Co/SiO 2 catalysts were prepared via galvanic replacement (GR) and employed for the hydrogenolytic ring-opening of methylcyclopentane (MCP). Selective deposition of the noble metals at the less expensive Co nanoparticle (NP) surface by GR greatly enhanced the utilization efficiency of the more active Pt or Pt and Ir atoms for the selective catalysis to the ring-opening reaction of MCP, as justified by comparison with catalysts from conventional impregnation preparation. The chemistry of GR was quantitatively studied by comprehension of the composition changes both in the preparation solution and in the solid samples. The structural features of GR catalysts were characterized as highly dispersed Pt or Pt and Ir clusters selectively deposited on Co NP surface. Compared to their counterparts from impregnation preparation, the GR catalysts showed much higher mass-specific activity normalized by overall noble metal loading (MSA NM ), due to the significantly enhanced utilization efficiency of Pt or Pt and Ir. In addition, the trimetallic Pt-Ir-Co/SiO 2 catalyst showed a distinctly higher MSA NM than the bimetallic Pt-Co/SiO 2 and Ir-Co/SiO 2 ones. This observation features a synergy between the highly dispersed Pt and Ir clusters in the catalysis, besides the enhanced noble metal utilization efficiency. Our catalytic data seem to suggest that a dicarbene mechanism was prevailing over the GR catalysts for the ring-opening reaction of MCP.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 51
·45864-45872
·
IF 3.289
Yafei Wang,Jiang Fan,Tianyi Li,Qiong Wang,Junwei Shi,Zuoming Qu,Hua Tan,Yu Liu,Weiguo Zhu
Two binuclear platinum metallomesogens possessing a 6,12-dihydro-indeno[1,2-b]fluorene bridge, FJ-1 and FJ-2, have been synthesised and characterised by 1H and 13C NMR, TOF-MS and elemental analysis. Their thermal properties were studied by polarised optical microscopy and differential scanning calorimetry. Upon photoexcitation in solution, both complexes exhibited dual fluorescence (1π–π*)/phosphorescence (3π–π*) emission covering most of the visible spectrum (from about 460 nm to 750 nm). This uncommon behaviour has been further investigated by time-resolved optical spectroscopy, including nanosecond time-resolved transient absorption spectroscopy, and further insights were obtained by means of density functional theory (DFT) and time-dependent DFT (TD-DFT). An organic light-emitting diode (OLED) using FJ-1 was prepared. Importantly the two emission bands are retained in electroluminescence. This result suggests that controlling spin–orbit coupling to obtain dual emission can provide an effective way of achieving broadband emission based on a single molecule.
研究领域:
化学
·
材料科学
·
光物理学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Lu Li,Feng Qin,Yongda Wang,Lixin Peng,Meng Kou,Zhiguo Zhang,Tao Jia
Metalloporphyrins with room-temperature phosphorescence (RTP) demonstrate great potential in information security and optoelectronic devices. However, the effects of different proportions of alcohols and binary mixtures on phosphorescence remain unclear, owing to varying nonradiative transition rate ( k nP ) across different solvents. In this study, we investigated the phosphorescence behavior of Platinum(II) meso -tetraphenylporphyrin (Pt-TPP) in different proportions of methanol-dimethyl sulfoxide (DMSO) liquid mixtures. The changes in the phosphorescence characteristics of Pt-TPP in solvents with varying ratios of methanol and DMSO were assessed through photoluminescence and time-resolved spectroscopy, and the observed variation in phosphorescence was attributed exclusively to k np . The increase of k np is attributed to the gradual narrowing of the energy gap between the excited triplet state of Pt-TPP and the energy levels of the two-component mixed solvent, and k np follows a mono-exponential trend with the energy gap. A linear relationship between the energy gap and the solvent composition was then established by analyzing the absorption spectra of mixtures with varying solvent proportions. Furthermore, a model was proposed to explain that k np exhibits a nonlinear dependence on solvent concentration, as well as the solvent-induced variations in phosphorescence.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2022
·
IF 9.231
Jing Yuan,Hong Duan,Lei Wang,Siyuan Wang,Yanbin Li,Jianhan Lin
Pathogen screening is an important step in preventing foodborne diseases . In this study, a hybrid nanozyme, metal organic framework decorated with palladium (Pd) and platinum (Pt) ( [email protected] /Pt), was innovatively synthesized and used with immune magnetic nanobeads (MNBs) for sensitive biosensing of Salmonella . First, immune [email protected] /Pt nanozymes and immune MNBs were mixed with target pathogens in a large-volume sample, resulting in effective isolation and specific label of target pathogens to form nanobead- Salmonella -nanozyme conjugates. Then, these conjugates were used to catalyze H 2 O 2 -TMB, and its color was changed from colorless to blue. Finally, catalysate absorption was measured to determine pathogen concentration. This colorimetric immunoassay could determine Salmonella typhimurium from 4 × 10 1 to 4 × 10 5 CFU/mL in 60 min with a detection limit of 32 CFU/mL.
研究领域:
生物技术
·
食品科学
·
分析化学
✓ 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）