Journal of Environmental Sciences
·
2023
·
IF 6.9
Anqi Lu,Xiaokang Xiang,Ming Lei,Shuangshuang Huang,Bingbing Liang,Siyu Zhao,Lihua Zhu,Heqing Tang
The reduction of nitrobenzene to aniline is very important for both pollution control and chemical synthesis. Nevertheless, difficulties still remain in developing a catalytic system having high efficiency and selectivity for the production of aniline. Herein, it was found that PdO nanoparticles highly dispersed on TiO 2 support (PdO/TiO 2 ) functioned as a highly efficient catalyst for the reduction of nitrobenzene in the presence of NaBH 4 . Under favorable conditions, 95% of the added nitrobenzene (1 mmol/L) was reduced within 1 min with an ultra-low apparent activation energy of 10.8 kJ/mol by using 0.5%PdO/TiO 2 as catalysts and 2 mmol/L of NaBH 4 as reductants, and the selectivity to aniline even reached up to 98%. The active hydrogen species were perceived as dominant species during the hydrogenation of nitrobenzene by the results of isotope labeling experiments and ESR spectroscopic. A mechanism was proposed as follows: PdO activates the nitro groups and leads to in-situ generation of Pd, and the generated Pd acts as the reduction sites to produce active hydrogen species. In this catalytic system, nitrobenzene prefers to be adsorbed on the PdO nanoparticles of the PdO/TiO 2 composite. Subsequently, the addition of NaBH 4 results in-situ generation of a Pd/PdO/TiO 2 composite from the PdO/TiO 2 composite, and the Pd nanoclusters would activate NaBH 4 to generate active hydrogen species to attack the adsorbed nitro groups. This work will open up a new approach for the catalytic transfer hydrogenation of nitrobenzene to aniline in green chemistry.
研究领域:
化学工程
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF PHOTOENERGY
·
2020
·
IF 1.88
Jing Yan,Xiaojuan Li,Bo Jin,Min Zeng,Rufang Peng
A series of TiO2, TiO2/Pd, and TiO2/PdO hollow sphere photocatalysts was successfully prepared via a combination of hydrothermal, sol-immobilization, and calcination methods. The structure and optical properties of the as-prepared samples were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Telleranalysis, Barrett-Joyner-Halenda measurement, and UV-Vis diffuse reflectance spectroscopy. The photocatalysis efficiencies of all samples were evaluated through the photocatalytic degradation of rhodamine B under visible light irradiation. Results indicated that TiO2/PdO demonstrated a higher photocatalytic activity (the photocatalytic degradation efficiency could reach up to 100% within 40 min) than the other samples and could maintain a stable photocatalytic degradation efficiency for at least four cycles. Finally, after using different scavengers, superoxide and hydroxyl radicals were identified as the primary active species for the effectiveness of the TiO2/PdO photocatalyst.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
·
2015
·Vol. 212
·期 8
·1789-1794
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IF 1.616
Chengnan Wang,Pei Zhao,Shantang Liu
SnO 2 hollow nanospheres (SnO 2 HNs) and different amount of PdO-doped SnO 2 HNs were successfully synthesized and applied to fabricate sensors for CO detection. The synthesized SnO 2 and PdO/SnO 2 materials have tetragonal and HN structure with a diameter of ∼180 nm, and the existence of Pd element is revealed by EDS and XPS. In addition, the sensors based on the pristine SnO 2 and Pd-loaded SnO 2 HNs were investigated for CO sensing properties. The experiment results indicated that materials of the best doping ratio is 1 mol%, because 1 mol% PdO/SnO 2 HN sensor had a lower optimized operating temperature (150 °C) and exhibited more excellent sensitivity than the other sensors for the detection of CO. Furthermore, the response value of 1 mol% PdO/SnO 2 HN sensor presented a linear relationship with CO concentration in the range 20–500 ppm CO at 150 °C. Meanwhile, 1 mol% PdO/SnO 2 HN sensor exhibited a remarkable selectivity to CO against volatile organic compounds. These results demonstrated that 1 mol% PdO/SnO 2 HNs are promising materials for application as a CO gas sensor when its working temperature is 150 °C. Comparison of PdO/SnO 2 hollow nanospheres with various amount of Pd loading for 200 ppm CO detection at different temperatures.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2021
·Vol. 32
·期 24
·28891-28908
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IF 2.478
Liu Guangdi,Cui Xiuxiu,Yao Lijia,Zhao Rongjun,Tian Xu,Li Diquan,Sun Chunyan,Wang Yude
This paper reports the synthesis of ZnO-SnO 2 nanocomposites modified by PdO nanoparticles named PdO-ZSO which are prepared by the one-step hydrothermal method at 160 °C for 12 h and gas sensing test to H 2 and C 4 H 10 inflammable gas. Meanwhile, PdO-ZSO nanoparticles are XRD, SEM, TEM, EDS, XPS and other characterization methods to further explain its morphological formation process. As the sensing materials, PdO-ZSO exhibits extraordinary gas sensing behaviors for hydrogen (H 2 ) and butane (C 4 H 10 ) and the response reaches 98 and 58 to H 2 and C 4 H 10 at operating temperature of 370 °C, respectively. And the response time and recovery time are both less than 2 s and 4 s respectively, with good repeatability and outstanding long-term stability. The existence of PdO is able to increase the resistance modulation range of heterostructure. And the enhanced gas sensing performances can be ascribed to the catalysis of noble metal doping and the formation of ternary heterostructure between PdO and ZnO-SnO 2 nanocomposites.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Wiewei Meng,Ling Wang,Yuehua Li,Huizhu Zhou,Zhangxing He,Wei Meng,Lei Dai
CoWO 4 -PdO dual phase composites were successfully prepared by self-demixing of the precursor CoPd x WO 4+x (x = 0, 2%, 5%, 10%) calcined at 800 °C and used as sensing electrodes for mixed-potential type NH 3 sensors based on yttria stabilized-zirconia (YSZ) electrolyte. The materials were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Field-emission scanning electron microscopy (FESEM), respectively. NH 3 response performance of the sensors to different concentrations of NH 3 (20–300 ppm) was evaluated at 350–500 °C. It was found that the sensors attached with CoWO 4 -PdO sensing electrode are much more sensitive to NH 3 than the CoWO 4 -based sensor. Among them, CoWO 4 -5%PdO based sensor gives the highest sensitivity (−76.8 mV/decade at 400 °C), the response signals (Δ V ) of the sensor vary linearly with the logarithm of the NH 3 concentrations in the range of 50–300 ppm at a given temperature. The sensor also exhibits well reproducibility, stability and long-term stability. Furthermore, compared with CoWO 4 -based sensor, the introduction of PdO in CoWO 4 makes the interference of NO 2 on the sensor significantly reduced from 100% to 50%, which is attributed to the fact that the second phase PdO depresses the adsorption of NO 2 .
研究领域:
材料科学
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传感技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2020
·
IF 7.216
Kuncan Wang,Wen Li,Junjie Huang,Jiale Huang,Guowu Zhan,Qingbiao Li
The extraction of metallic nanoparticles from perovskite-type oxides (ABO 3 ) under mild reducing conditions is a novel way to prepare well-dispersed supported catalysts (B/AO δ ). Herein, we found that the encapsulated PdO in perovskite LaCoO 3 (PdO@LaCoO 3 ) could facilitate the phase transformation of the perovskite structure at a low temperature owing to both strong H 2 spillover of Pd and intimate interaction between the encapsulated PdO and LaCoO 3 . The pure LaCoO 3 without PdO was relatively inert to CO 2 hydrogenation (CO 2 conversion <4%). In contrast, PdO@LaCoO 3 exhibited excellent CO 2 methanation performance with 62.3% CO 2 conversion and >99% CH 4 selectivity. The characterization results demonstrated that the catalytically active Co 2 C was in-situ formed by carburization of the extracted Co 0 during CO 2 methanation for the PdO@LaCoO 3 sample. Whereas, the LaCoO 3 with surface supported PdO (PdO/LaCoO 3 ) showed a weak interaction and remained a perovskite structure with few Co 2 C active centers after the catalytic reaction, which was similar to the parent LaCoO 3 . Accordingly, the PdO/LaCoO 3 showed an inferior catalytic performance with 31.8% CO 2 conversion and 87.4% CH 4 selectivity. Therefore, the designed encapsulation structure of PdO within perovskite is critical to extract metallic NPs from perovskite-type oxides, which has the potential to prepare other integrated nanocatalysts based on perovskite-type oxides.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 40
·22875-22882
·
IF 3.049
Pengjian Wang,Tingbiao Yuan,Huifang Yuan,Xiaoyan Zheng,Hamza Ijaz,Junfeng Hui,Daidi Fan,Yuxin Zhao,Shi Hu
In this paper, we developed a simple two-step route to prepare a PdO/SnO2 heterostructure with the diameter of the SnO2 and PdO nanoparticles at about 15 nm and 3 nm, respectively. In the evaluation temperature window between 80 °C and 340 °C, PdO/SnO2 shows the best response to 100 ppm of CO at 100 °C with fast response time (14 s) and recovery time (8 s). Furthermore, the PdO/SnO2 nanoparticles exhibit a low detection limit and good selectivity to CO against interfering gases as well as rarely-seen low-temperature stability and reversibility. Such enhanced gas sensing performance could be attributed to both the ultrafine structure of PdO and the synergy between PdO and SnO2. The results clearly indicate the application of PdO/SnO2 as a pratical low-temperature sensing material for CO.
研究领域:
材料科学
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传感器技术
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NANOTECHNOLOGY
·
2022
·Vol. 33
·期 38
·385703
·
IF 3.953
Mei Zhang,Lin Cui,Qiqi Mao,Ziqiang Wang,Hongjie Yu,You Xu,Xiaonian Li,Liang Wang,Hongjing Wang
Exploring cost-effective and highly active electrocatalysts is of great significance for sustainable electrochemical NH3 synthesis. Palladium (Pd)-based catalysts have been unanimously considered as one of the most efficient catalysts for the nitrogen reduction reaction (NRR). Herein, self-supported mesoporous Pd film with partial oxidation on Ni foam (mPd-PdO/NF) was synthesized through the micelle-assisted chemical replacement method coupled with air oxidation under 260 °C, and the mPd-PdO/NF electrocatalyst exhibited superior NRR performance with the maximum values of rNH3 (24.8 mg h−1 mgcat.−1) and FE (16.64%) were obtained at −0.1 V, relative to the single counterparts (mPd/NF and mPdO/NF). It is proposed that both metallic Pd and its oxide domains when co-existing with a phase boundary between them can facilitate nitrogen activation and hydrogenation, resulting in an enhanced NRR performance. This work provides an inspiring strategy for the rational design of highly active and durable metal–metal–oxide nanoarchitectonics for ammonia electrosynthesis.
研究领域:
电化学
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材料科学
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催化
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可持续化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2021
·
IF 5.909
Jie Hu,Xueqing Xiong,Wangwang Guan,Haizhu Long
In this study, a structurally well-designed PdO@WO 3 core–shell, p–n heterojunction architecture was fabricated using a facile hydrothermal method. Its material characterization was performed via X-ray diffractometry, X-ray photoelectron spectroscopy, electron scanning microscopy, and transmission electron microscopy analyses. Besides, the gas sensing properties of pure WO 3 , PdO–WO 3 , and PdO@WO 3 nanocomposites were investigated. By benefiting from the unique synergistic effect between catalytic sensing and p–n heterojunction structure, the PdO@WO 3 core–shell nanostructure showed considerably enhanced acetone sensing performance compared with the other structures; especially, its response toward 50 ppm acetone gas was up to 40, four times higher than that of the pure WO 3 sensor. Its response/recovery times were also significantly reduced and its optimal operating temperature decreased from 250 °C to 200 °C. Finally, the possible sensing mechanism for the proposed PdO@WO 3 core–shell, p–n heterojunction architecture is discussed here; the considerable enhancement in the acetone sensing capability could be attributed to its well-designed fabrication.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 10
·4042-4048
·
IF 3.288
Mufei Liu,Fang Cui,Qinghai Ma,Linxu Xu,Jiajia Zhang,Ruliang Zhang,Tieyu Cui
We designed a facile and green self-assembly route for the large-scale production of bimetallic coordination polymer–Zn(MAA)2/Pd(II) nanoribbons by employing two terminal units with distinct hard–soft properties of the smallest semi-rigid methacrylate anion (MAA−) to combine with two different metal ions. The COO− (chemically hard base) served as the initial unit, which was applied to coordinate with the Zn2+ ions for constructing the host network of this Janus CPs by facilely adjusting the proportion of ethanol/water to control the degree of solvation. After soaking in an ethanol solution of PdCl2, the alkene units (chemically soft base) act as secondary donors to load the soft noble metal Pd2+ ions and form Zn(MAA)2/Pd(II) nanoribbons, which are ideal precursors of ZnO/PdO nanoribbons. By pyrolyzing the dual metal ion equipped Zn(MAA)2/Pd(II) precursors, ZnO nanoribbon supported PdO nanoparticles (NPs) with a well-defined structure were facilely fabricated on a large scale. Furthermore, the as-obtained ZnO/PdO nanoribbons exhibit efficient catalytic performance for the reduction of 4-NP, which can convert 99.3% of the substrates within 6 min. This superior catalytic performance may be attributed to the well-dispersed PdO nanoparticles as well as the absence of additional agents introduced a green synthetic method.
研究领域:
材料科学
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催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Wenhui Zou,Yingcen Liu,Caicheng Song,Hua Lin,He Huang,Wanyue Ye,Rongwen Lu,Shufen Zhang
A series of PdO@MCM-41-x was in situ synthesized by a facile one-pot method, and their catalytic performance for dehydrogenation of formic acid was investigated. The PdO nanoparticles were immobilized in MCM-41 channel with small size of 2.2–2.5 nm due to the confinement of mesoporous silica . The initial turnover frequency (TOF) of as-prepared catalyst can reach 1096 h −1 at 323 K with 100% hydrogen selectivity. The hydrogen production activity was better than that of catalyst priorly reduced by hydrogen because of the gradual reduction of PdO nanoparticles and generation of fresh Pd(0) during the formic acid dehydrogenation process, which was confirmed by XPS characterization and catalytic system monitoring. It provides a new way for the preparation of simple and efficient catalysts for hydrogen production , which has great application potential.
研究领域:
化学
·
催化材料科学
✓ 已验证
DOI
高影响因子
ACS Catalysis
·
2017
·
IF 10.614
Xuelin Zou,Zebao Rui,Hongbing Ji
An alumina-supported core–shell-structured NiO@PdO catalyst was prepared for lean CH4 combustion. NiO@PdO plays two roles in promoting the reaction. First, the enhanced NiO-PdO interfacial action accelerates the regular tetragonal PdO lattice construction, stabilizes the PdO particles, and suppresses the hydroxyl/water adsorption during the reaction. Second, the dispersion of shell PdO particles over core NiO improves PdO exposure and utilization efficiency. NiO@PdO/Al2O3 with a molar Ni/Pd ratio of 2/1 exhibits a (>)99% CH4 conversion and a good stability at 400 °C with a low 0.2 wt % Pd loading amount, which is among the best of the state-of-the-art Pd-based catalysts with respect to turnover frequency, Pd utilization efficiency, and Ni addition amount. Such interface-promoted core–shell-structured catalyst design strategy is inspiring for improving noble metal utilization efficiency in CH4 oxidation and other related reaction systems.
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）