| 1. |
- Liang, Jie, et al.
(författare)
-
A Crystalline Mesoporous Germanate with 48-Ring Channels for CO2 Separation
- 2015
-
Ingår i: Angewandte Chemie International Edition. - : Wiley. - 1433-7851 .- 1521-3773. ; 54:25, s. 7290-7294
-
Tidskriftsartikel (refereegranskat)abstract
- One of the challenges in materials science has been to prepare crystalline inorganic compounds with mesopores. Although several design strategies have been developed to address the challenge, expansion of pore sizes in inorganic materials is more difficult compared to that for metal-organic frameworks. Herein, we designed a novel mesoporous germanate PKU-17 with 3D 48 x 16 x 16-ring channels by introducing two large building units (Ge-10 and Ge-7 clusters) into the same framework. The key for this design strategy is the selection of 2-propanolamine (MIPA), which serves as the terminal species to promote the crystallization of Ge-7 clusters. Moreover, it is responsible for the coexistence of Ge-10 and Ge-7 clusters. To our knowledge, the discovery of PKU-17 sets a new record in pore sizes among germanates. It is also the first germanate that exhibits a good selectivity toward CO2 over N-2 and CH4.
|
|
| 2. |
- Liu, Ben, et al.
(författare)
-
A facile synthesis of Fe3C@mesoporous carbon nitride nanospheres with superior electrocatalytic activity
- 2016
-
Ingår i: Nanoscale. - : Royal Society of Chemistry (RSC). - 2040-3364 .- 2040-3372. ; 8:10, s. 5441-5445
-
Tidskriftsartikel (refereegranskat)abstract
- We report a colloidal amphiphile-templating approach to preparing nanosized Fe3C encapsulated within mesoporous nitrogen-doped carbon nanospheres (Fe3C@mCN). The obtained Fe3C@mCN hybrids having a high surface area and ultrafine Fe3C nanocrystals exhibited superior activity and durability for oxygen reduction.
|
|
| 3. |
- Liu, Ben, et al.
(författare)
-
Unconventional structural and morphological transitions of nanosheets, nanoflakes and nanorods of AuNP@MnO2
- 2016
-
Ingår i: Journal of Materials Chemistry A. - : Royal Society of Chemistry (RSC). - 2050-7488 .- 2050-7496. ; 4:17, s. 6447-6455
-
Tidskriftsartikel (refereegranskat)abstract
- Two-dimensional (2-D) layered inorganic materials with ultra-high surface area and mechanical strength have shown impressive photo-/electro-catalytic activities. We herein report a facile synthetic strategy to grow monodispersed 2-D MnO2 nanosheet on an individual gold nanoparticle (AuNP@MnO2 nanosheet), and demonstrate that the strongly interacted AuNP and MnO2 nanosheet could greatly improve the electrocatalytic activity of the MnOx family for electrocatalytic oxygen reduction reactions (ORRs). AuNP@MnO2 nanosheets were prepared using a hydrothermal reduction of KMnO4 by citrate ligands capped on AuNPs. Because of the metastability of the layered MnO2 nanosheets, we observed unconventional structural and morphological transitions of amorphous MnO2 nanosheets to delta-MnO2 nanoflakes, and eventually to alpha-MnO2 nanorods under hydrothermal conditions. The layered MnO2 nanosheets underwent a structural expansion to nanoflakes before the curling and re-folding of layered MnO2 nanosheets occurred. The intermediate states and structural transitions via a layer compression, for the first time, were experimentally recorded at a single-NP scale using electron microscopy. Moreover, we found the electrocatalytic activity of AuNP@MnO2 nanosheets was enhanced roughly 30-40 times, compared to that of pure MnO2 nanosheets and AuNPs. The strong interaction of metal-oxide interfaces (MnO2 nanosheets and AuNPs) was likely responsible for the improved electrocatalytic activity. This interaction of MnO2 and AuNPs was weakened in the course of hydrothermal treatment where partially positively charged Au+ was reduced at elevated temperatures, accompanying with the decrease of ORR activity. This insight into the effect of topological nanostructures and metal-oxide interactions on the electrocatalytic performance of the MnOx family is believed to illustrate an alternative pathway to develop new efficient electrocatalysts.
|
|
| 4. |
- Yao, Qingxia, et al.
(författare)
-
Series of Highly Stable Isoreticular Lanthanide Metal-Organic Frameworks with Expanding Pore Size and Tunable Luminescent Properties
- 2015
-
Ingår i: Chemistry of Materials. - : American Chemical Society (ACS). - 0897-4756 .- 1520-5002. ; 27:15, s. 5332-5339
-
Tidskriftsartikel (refereegranskat)abstract
- A series of highly porous isoreticular lanthanide-based metal organic frameworks (LnMOFs) denoted as SUMOE-7I to SUMOE-7IV (SU = Stockholm University; Ln = La, Ce, Pr, Nd, Sm, Eu, and Gd) have been synthesized using tritopic carboxylates as the organic linkers. The SUMOF-7 materials display one-dimensional pseudohexagonal channels with the pore diameter gradually enlarged from 8.4 to 23.9 angstrom, as a result of increasing sizes of the organic linkers. The structures have been solved by single crystal X-ray diffraction or rotation electron diffraction (RED) combined with powder X-ray diffraction (PXRD). The SUMOF-7 materials exhibit robust architectures with permanent porosity. More importantly, they exhibit exceptionally high thermal and chemical stability. We show that, by inclusion of organic dye molecules, the luminescence properties of the MOFs can be elaborated and modulated, leading to promising applications in sensing and optics.
|
|
| 5. |
- Zheng, Haoquan, et al.
(författare)
-
Ultra-small mesoporous silica nanoparticles as efficient carriers for pH responsive releases of anti-cancer drugs
- 2015
-
Ingår i: Dalton Transactions. - : Royal Society of Chemistry (RSC). - 1477-9226 .- 1477-9234. ; 44:46, s. 20186-20192
-
Tidskriftsartikel (refereegranskat)abstract
- Mesoporous silica has emerged as one of the most promising carriers for drug delivery systems. However, the synthesis of ultra-small mesoporous silica nanoparticles (UMSNs) and their application in drug delivery remains a significant challenge. Here, spherical UMSNs (similar to 25 nm) have been synthesized and tested as drug carriers. Anti-cancer drugs mitoxantrone (MX), doxorubicin (DOX) and methotrexate (MTX) have been utilized as model drugs. The pH-responsive drug delivery system can be constructed based on electrostatic interactions between carriers and drug molecules. The UMSNs could store drugs under physiological conditions and release them under acidic conditions. Different pH-responsive release profiles were obtained in phosphate buffer solutions (PBSs) at the designed pH values (from 4.0 to 7.4). MX and DOX can be used in the pH-responsive delivery system, while MTX cannot be used. Furthermore, we found that the physiological stabilities of these drug molecules in UMSNs are in a decreasing order MX > DOX > MTX, which follows the order of their isoelectric point (pI) values.
|
|
| 6. |
|
|
