ENERGY & FUELS
·
2021
·
IF 3.605
Chunli Li,Mingxia Zhang,Hao Li,Yahui Zhang
As an inevitable harmful waste, biomass tar has always been considered as one of the challenges of biomass resource utilization. In this paper, biomass tar is used as the carbon source for the preparation of biocarbon with different activators in one pot. The Pd@biocarbon catalysts with low Pd loading were synthesized for hydrodeoxygenation (HDO) of vanillin in the presence of poly(methylhydrosiloxane) (PMHS) as the hydrogen donor, avoiding gaseous hydrogen and high temperature. The effects of different activators (KOH and K2FeO4) and carbonization temperature on the structure and catalytic performance of the as-prepared Pd@biocarbon catalysts were investigated in detail. The characterization results showed that Pd@BC-KFe-800 activated by K2FeO4 and carbonized at 800 °C had abundant surface acid groups and a high degree of graphitization. Further evaluation of the catalytic activity showed that Pd@BC-KFe-800 had the highest catalytic activity and can achieve 94.6% vanillin conversion at 65 °C for 2 h. The mechanism study indicated that the high HDO activity is attributed to the synergistic effect of the active metal Pd and biocarbon with surface acidic hydroxyl groups and the good graphitization structure. Compared with KOH, K2FeO4 can improve the graphitization degree of biocarbon and lead to catalysts with stronger acidity, providing more acid sites for the HDO of vanillin. Furthermore, the as-prepared Pd@BC-KFe-800 catalyst has shown favorable recyclability after four uses. These findings not only provide a new idea for the green treatment of waste biomass tar but also give a reference value for the HDO of bio-oil under mild conditions.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 25
·14507-14514
·
IF 12.732
Wenyan Si,Ze Yang,Xiuli Hu,Qing Lv,Xiaodong Li,Fuhua Zhao,Jianjiang He,Changshui Huang
Zero valence palladium (Pd(0)) nanoparticles have been reported to be more favorable to the oxygen reduction reaction (ORR) than palladium oxide (PdO). However, PdO is normally concomitant in Pd(0) nanoparticles. Herein, we developed an inventive method to prepare pure Pd(0) nanoparticles supported with hydrogen-substituted graphyne (Pd/HsGY) and its nitrogen-doped sample (Pd/N–HsGY). Pd(0) nanoparticles were obtained by reducing the atomically dispersed bivalent Pd, which is easy to be anchored on HsGY. The unique sp-hybridized carbon atoms in HsGY exhibited obvious extrinsic charge compensation to maintain the supported Pd nanoparticles to zero valence state. The as-prepared samples, especially Pd/N–HsGY, displayed excellent activity for ORR, higher than that of commercial Pd/C and Pt/C. In an alkaline medium, the mass activity of Pd/N–HsGY at 0.8 V (vs. RHE) was 2.1 times higher than that of Pd/C, and 1.7 times higher than that of Pt/C. While in an acidic medium, the mass activity of Pd/N–HsGY was 17.7 and 1.6 times Pd/C and Pt/C, respectively. Pd/N–HsGY based Zn–air battery exhibited higher power density than Pt/C-based battery and superior stability for more than 300 hours. Density functional theory calculations confirmed that Pd(0) nanoparticles, Pd/HsGY and Pd/N–HsGY were favorable to ORR. This method brings new perspectives for designing zero valence metal nanoparticles for electrocatalytic applications.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2020
·
IF 5.647
Lu Zhou,Jixian Yang,Fang Ma,Shanshan Pi,Aiqi Tang,Ang Li
Palladium (Pd) is extremely expensive due to its scarcity and excellent catalytic performance. Thus, the recovery of Pd has become increasingly important. Herein, microbial extracellular polymeric substances (EPS) and magnetic nanocomposite EPS@Fe 3 O 4 were applied to recover Pd catalysts from Pd(II) wastewater. Results indicated that Pd(II) was reduced to Pd (0), which was then adsorbed by EPS (101.21 mg/g) and EPS@Fe 3 O 4 (126.30 mg/(g EPS)). After adsorbing Pd, EPS@Fe 3 O 4 could be collected by magnetic separation. The recovered Pd showed excellent catalytic activity in the reduction of methylene blue (MB). The pseudo-second-order kinetic model and Redlich-Peterson model best fit the adsorption results. According to spectral analysis, Pd(II) was reduced to Pd (0) by chemical groups in EPS and EPS@Fe 3 O 4 , and the hydroxyl had a chelating effect on adsorbed Pd. Therefore, EPS@Fe 3 O 4 is an efficient adsorbent for recovering Pd from Pd(II) wastewater.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Fangfang Ren,Xuanrong Chen,Rong Xing,Yukou Du
Anode catalyst is one of the core components of fuel cell, but its poor catalytic activity, short lifespan, and high price are tricky problems to the commercialization of fuel cell. Herein, a novel rod-like MnO 2 decorated reduced graphene oxide (RGO) supported Pd hybrid (Pd/RGO-MnO 2 ) has been designed, which manifests more negative onset oxidation potential, higher peak current density, and better long-term stability relative to Pd/RGO and pure Pd catalysts when serving for ethylene glycol electrooxidation . This enhancement may be due to the addition of MnO 2 , which can effectively promote the adsorption of hydroxyl at a lower potential and produce a strong electronic interaction with Pd, as confirmed by X-ray photoelectron spectroscopy (XPS) technique. In view of its excellent performance and low cost, Pd/RGO-MnO 2 is considered to be a potential and effective anode catalyst for DEGFCs.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2020
·
IF 4.551
Yue Zhang,Li Wang,Nan Wang,Guohua Gao,Zhiyong Pan,Baoning Zong
Monodispersed mesoporous SBA-15 silica was synthesized by adding n -decane to conventional synthesis recipe. Pd catalysts for 2-alkyl-anthraquinone hydrogenation were then prepared on the as-synthesized SBA-15 and characterized by scanning and transmission electron micrographs, X-ray diffraction, XPS spectroscopy and N 2 adsorption-desorption. At the molar ratio of n -decane to P123 (C10/P123) ranging between 120 and 240, monodispersed SBA-15, together with the shortened length of pore channels, expanded size of mesopores and decreased proportion of micropores could be obtained. The Pd catalyst on SBA-15 synthesized with 240 in C10/P123 exhibited the superior catalytic performance. The initial hydrogenation rate of 2-ethyl-, tert-butyl- and amyl-anthraquinone increases by approximately 300%, 183% and 150% compared with that on SBA-15 synthesized using a recipe without n -decane, with the selectivity to active anthraquinone of >99%.
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2020
·Vol. 151
·期 7
·1902-1910
·
IF 2.482
Yin Danyang,Zhang Jinli,Li Wei,Fu Yan
Abstract Herein Pd nanocatalysts for transfer hydrogenation were synthesized by using hyaluronic acid (HA) as both the reductant and the stabilizer. The effects of molecular weight of HA, molar ratio of [HA]/[Na 2 PdCl 4 ] and reduction temperature, were evaluated in Pd-catalyzed transfer hydrogenation of 4-nitrophenol. The most active Pd NPs show the TOF value of 131.07 h −1 at 50 °C with the equimolar mixture of formic acid and sodium formate. Further, uniformly distributed Pd NPs were successfully synthesized through the reduction of Pd (II) precursors on HA-modified magnetic NPs, which were constructed through electrostatic layer-by-layer assembly. The hybrid catalysts also exhibit high activity with the mixed hydrogen source. This work paves a promising way to construct highly active hybrid catalysts through the combination of in-situ reduction and electrostatic layer-by-layer methods. Graphic Abstract
✓ 已验证
产品关联
DOI
高影响因子
CANCER LETTERS
·
2020
·
IF 7.36
Huimin Tao,Lu Cheng,Lihua Liu,Hong Wang,Zhijie Jiang,Xu Qiang,Lijun Xing,Yifeng Xu,Xinying Cai,Jing Yao,Min Wang,Zheng Qiu
Antibodies blocking the PD-1/PD-L1 pathway have achieved great success. However, some disadvantages of antibodies have been found, which limit their clinical applications. Peptide antagonists are alternatives to antibodies in PD-1/PD-L1 blockage, but successful studies in this area are limited. A PD-1 targeting peptide, P–F4, was identified using phage display. P–F4 bound PD-1 with an affinity of 0.119 μM, inhibited PD-1/PD-L1 interaction at the cellular level and modulated T cell activity in vitro . We have overcome the poor solubility and rapid degradation problems of this peptide by packaging P–F4 in nanoparticles. In vivo experiments demonstrated that P–F4 nanoparticles could strongly inhibit tumor growth in a CT26 mouse model. Further research revealed that treatment of P–F4 nanoparticles increased CD8+T cells and reduced Tregs in the tumor microenvironment and tumor-draining lymph nodes. It was shown that treatment of P–F4 nanoparticles also increased lymphocytic activities, including proliferation, cytokine secretion and cytolytic activity. Moreover, computer modeling suggested that the P–F4 binding site to PD-1 overlaps with the PD-L1 binding surface. In this study, a peptide candidate for cancer immunotherapy was provided, and its working mechanisms were studied.
✓ 已验证
DOI
PubMed
高影响因子
Nanoscale
·
2021
·Vol. 13
·期 5
·3208-3213
·
IF 7.79
Shuli Yin,Ziqiang Wang,Songliang Liu,Shiqian Jiao,Wenjing Tian,You Xu,Xiaonian Li,Liang Wang,Hongjing Wang
The design of bimetallic core–shell nanostructures with mesoporous surfaces is considered significant to strengthen the catalytic activity and stability for direct methanol fuel cells. Here, we report a flexible method to synthesize Au@Pd core–shell mesoporous nanoflowers (Au@mPd NFs) with Au core coated with mesoporous Pd nano-petals, in which polymeric micelle-assembled structures are used as templates to induce the formation of mesopores. Benefiting from the electronic and structural effects, Au@mPd NFs show excellent electrocatalytic activity and stability for methanol oxidation reaction in alkaline electrolytes. This study demonstrates a versatile strategy for the fabrication of core–shell mesoporous nanoflowers with adjustable composition.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2020
·
IF 5.162
Haichuan Zhang,Yang Liu,Shiyu Fu,Yulin Deng
Upgrading of lignin derived bio-oil is an essential step for producing sustainable bio-based chemicals and fuel. Taken into account that α hydroxyl is the abundant functional group in lignin, high effective and selective catalytic alcoholysis for cleaving the C α -OH linkages would be desirable. However, an in-depth understanding of the reaction mechanisms involved in the cleavage of C aromatic -C α and C α -O bonds over a novel catalyst is still needed. Herein, we report an efficient liquid-phase hydrogen transfer strategy for the selective hydrodeoxygenation of a non-phenolic lignin model compound, 3,4-dimethoxybenzyl (veratryl) alcohol, under mild conditions. By employing iso-propanol as solvent and H-donor, and palladium nanoparticles immobilized on nitrogen-doped carbon (Pd/CN X ) as efficient multifunctional catalyst, veratryl alcohol dehydroxylation exhibited almost 100% conversion along with very high selectivity for 1,2-dimethoxy-benzene (46%) and 3,4-dimethoxytoluene (54%). Compared with other Pd catalysis, the Pd/CN X has excellent catalytic performances and exhibits higher selectivity for 3,4-dimethoxytoluene under incorporation with 1% HCOOH at 220 °C. The proportion of Pd (0) significantly increases in Pd/CN X catalyst when introduced into N precursor because of its highly dispersed Pd NPs and preventing the reoxidation of Pd (0). The dehydrogenation reaction occurred through the hydrogen generation of a secondary alcohol. Then, the C α -OH and C aromatic -C α bonds of veratryl alcohol were selectively cleaved by catalytic transfer hydrogenolysis . The alcoholysis mechanism is supported by dispersion-corrected density functional theory computations.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Pingping Wu,Lei Song,Yue Wang,Xuehua Liu,Zhengke He,Peng Bai,Zifeng Yan
Achieving the balance between the catalytic activity and product selectivity still remains a challenge in partial oxidation processes, because the products are prone to be over-oxidized. Lewis acids (such as AlCl 3 ) have previously been identified to interact with C O groups, which can prevent the ketone products from further transformation. In this work, ZrO 2 promoted Au-Pd/γ-Al 2 O 3 catalyst was designed to enhance the benzaldehyde selectivity by generating more surface Lewis acid site on ZrO 2 -modified alumina. Results show that the introduction of ZrO 2 (5%) resulted in the formation of more surface Lewis acid sites, which improved the benzaldehyde selectivity through the strengthened interaction between the Lewis acid sites and C O groups in benzaldehyde. Besides, the addition of small amount of ZrO 2 enhanced the noble metal dispersion and led to the formation of more active sites to improve the oxygen transfer during the reaction.
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Jiuxuan Zhang,Chunhua Zhang,Hong Jiang,Yefei Liu,Rizhi Chen
Selective hydrogenation of phenol is a green strategy to produce cyclohexanone. Achieving high phenol conversion and cyclohexanone selectivity under mild conditions is a significant challenge in the design and synthesis of highly efficient catalysts. Herein, a highly efficient Pd@CN-rGO catalyst is synthesized by supporting Pd nanoparticles on the composite of ZIF-derived N-doped carbon and reduced GO (CN-rGO), which is prepared via annealing the composite of layered ZIF-L-Co and GO. The as-fabricated Pd1.2@CN-rGO-15 catalyst shows superior catalytic performance in phenol hydrogenation, and its turnover frequency (TOF) is 33.7 h–1, 3.2 times higher than that of Pd1.6/rGO and 1.5 times higher than that of Pd0.9@CN-rGO-0. The synergistic effect of CN and rGO leads to the uniform dispersion of Pd, high phenol adsorption ability, and strong antioxidizability of Pd, which contributes to the superior catalytic performance. More importantly, Pd@CN-rGO has good reusability in phenol hydrogenation. These findings will offer new insights into the development of high-performance catalysts for the selective hydrogenation of phenol.
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2020
·
IF 7.182
Fengxia Wang,Xu Ding,Xiaobo Niu,Xianyi Liu,Wei Wang,Ji Zhang
Although core-shell structure is favored by many applications, preparing it with green way is rarely been reported. Herein, a core-shell structured Cu@Pd-CS nanocomposite is greenly fabricated utilizing a natural chitosan and applied to glucose detection. As-obtained Cu@Pd-CS nanoparticles were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and powder X-ray diffraction (XRD). When applied to glucose detection, the Cu@Pd-CS exhibits good stability, sensitivity and anti-interference. Moreover, it has a good linear relationship in glucose concentrations range of 0.1−1 mM with the sensitivity of 1.53 μA mM −1 cm −2 and 1−10 mM with the sensitivity of 23.00 μA mM −1 cm −2 . This work proves the practicability of building metal-based core-shell structure nanoparticles with green resources and glucose detection application.
✓ 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）