Pollen-structured hierarchically meso/macroporous silica spheres with supported gold nanoparticles for high-performance catalytic CO oxidation

Yao, Xinlei; Zhou, Shujun; Zhou, Han; Fan, Tongxiang

doi:10.1016/j.materresbull.2017.04.016

Cited by 9 publications

(6 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fourier-transform infrared (FTIR) spectra were performed to analyze the chemical structures of as-synthesized PC, PPy, and PC-PPy shown in Figure d. The broad bands of PC near 3250, 2920, and 1624 cm –1 correspond to the stretching vibrations of hydroxyl groups (−OH), the asymmetric stretching vibrations of methylene groups (−CH 2 −), and the vibrations of amides (−NHR), respectively, which are consistent with the organic composition of pollen cells . The spectrum of PPy exhibits sorption peaks at 1552 and 1045 cm –1 , corresponding to the intra-ring stretching of the CC bond in the pyrrole ring and internal deformation of the plane of the N–H bond, respectively.…”

Section: Resultsmentioning

confidence: 73%

“…Inspired by the water transpiration process in trees where water is taken up by plants and released to the atmosphere through the leaves, during which the mesophyll cells release water through the stomata by the photosynthesis or respiration process, and the opening/closure of the stomata bordered by guard cells is dominated by the reducing/increasing water potential of guard cells induced by enhancement/suppression of photosynthesis or respiration, here we develop a nature-inspired design concept of an AWH device based on natural rape pollen cells derived LiCl@pollen cell–polypyrrole (LiCl@PC-PPy) sorbent. The natural rape pollen cells are first pretreated to remove the pectin, amino acids, vitamins, proteins, and other substances, forming the hierarchical hollow structured pollen cell (PC) precursor. − The PPy photothermal material is in situ polymerization on the skeleton of the PC particle. The LiCl@PC-PPy sorbent is obtained by infiltrating the LiCl hygroscopic agent into the cages of PC-PPy.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Hierarchical Natural Pollen Cell-Derived Composite Sorbents for Efficient Atmospheric Water Harvesting

Liu

et al. 2022

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Freshwater scarcity is a critical challenge threatening human survival especially due to poverty and arid and off-grid regions. Sorption-based atmospheric water harvesting (AWH) has emerged as a promising strategy for clean water production. However, most of the high-capacity sorbents are limited by the poor sorption/desorption kinetics and uncontrollable liquid leakage problem. Inspired by the plant transpiration process, we develop an environmentally friendly LiCl@pollen cell–polypyrrole (LiCl@PC-PPy) composite sorbent by confining the LiCl hygroscopic agent in the cages of the PC-PPy. The composite sorbent exhibits much improved sorption/desorption kinetics owing to the hydrophilicity of the hierarchical porous structure of the pollen cells, which provides abundant water sorption active sites and diffusion pathways and forms a concave meniscus on cell skeletons to maximize the thermal utilization efficiency. Moreover, the big cavities of the PC-PPy cages can serve as a water reservoir to reduce liquid leakage. As a result, the sorbent can capture atmospheric water to 85% of its own weight under 60% relative humidity (RH) within 2 h and rapidly release the water within 1 h under weak light irradiation of 0.8 sun. As a proof-of-concept demonstration, the fabricated AWH device can absorb 1.55 gwater/gsorbent at night and collect 1.53 gwater/gsorbent of water in 1-day outdoor operation, and the collected water can meet the drinking water standards defined by the World Health Organization (WHO) and Environmental Protection Agency (EPA).

show abstract

Section: Resultsmentioning

confidence: 73%

Section: Introductionmentioning

confidence: 99%

Hierarchical Natural Pollen Cell-Derived Composite Sorbents for Efficient Atmospheric Water Harvesting

Liu

et al. 2022

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…The adsorption isotherm of Au-PS-5 exhibits a sharp increase in the low-pressure region ( P / P o < 0.1), which indicates the presence of micropores. The isotherm in the range of 0.4 < P / P o < 0.9 shows a type-IV hysteresis, which is typical for mesoporous structures . The pore size distributions evaluated from the adsorption curve by using the density functional theory method show a bimodal distribution, one peak centered at ca.…”

Section: Resultsmentioning

confidence: 94%

“…The isotherm in the range of 0.4 < P/P o < 0.9 shows a type-IV hysteresis, which is typical for mesoporous structures. 33 The pore size distributions evaluated from the adsorption curve by using the density functional theory method show a bimodal distribution, 34 one peak centered at ca. 1.8 nm (micropores) and another at ca.…”

Section: Resultsmentioning

confidence: 99%

Porous Silica-Coated Gold Sponges with High Thermal and Catalytic Stability

Lee

Kang

Dey

et al. 2018

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

A method to fabricate porous silica-coated Au sponges that show high thermal and catalytic stability has been developed for the first time. The method involves dense surface functionalization of Au sponges (made by self-assembly of Au nanoparticles) with thiolated poly(ethylene glycol) (SH-PEG), which provides binding and condensation sites for silica precursors. The silica coating thickness can be controlled by using SH-PEG of different molecular weights. The silica-coated Au sponge prepared by using 5 kDa SH-PEG maintains its morphology at temperature as high as 700 °C. The calcination removes all organic molecules, resulting in porous silica-coated Au sponges, which contain hierarchically connected micro- and mesopores. The hierarchical pore structures provide an efficient pathway for reactant molecules to access the surface of Au sponges. The porous silica-coated Au sponges show an excellent catalytic recyclability, maintaining the catalytic conversion percentage of 4-nitrophenol by NaBH to 4-aminophenol as high as 93% even after 10 catalytic cycles. The method may be applicable for other porous metals, which are of great interests for catalyst, fuel cell, and sensor applications.

show abstract

“…Recently, Fan et al have prepared an exceptional pollen-structured hierarchically meso-/macroporous silica spheres (PHMSs) created from unique rape pollen grains and a triblock copolymer poly(ethylene oxide-block-propylene oxide-block-ethylene oxide) (P123) as templates [73]. The PHMSs are enclosed of mesoporous walls, which create a macroporous structure repeating the net-like morphology of the pollen grain exine.…”

Section: New Methodsmentioning

confidence: 99%

Silica-Supported Gold Nanocatalyst for CO Oxidation

Qureshi¹,

Jaseer²

2019

Gold Nanoparticles - Reaching New Heights

View full text Add to dashboard Cite

Even though gold is inert in its bulk practice, greatly disseminated gold nanoparticles (Au NPs) with dimensions less than 5 nm have been found to be active for a number of oxygen transfer reactions, particularly for low-temperature CO oxidation. The catalytic activity not only be subject to the particle size of Au but also on the nature of the support and the synthesis method of the catalyst. These factors are frequently interrelated such that their separate contributions cannot be easily unraveled. Also, the activity of a supported Au catalyst is ruled by a complex combination of contributions of the particle morphology, metal dispersion, and electronic properties of the gold. Higher catalytic activity is being observed for Au NPs supported on reducible metal oxides such as TiO 2 , Co 3 O 4 , CeO 2 , and Fe 2 O 3. However, silica is an inert, inexpensive, and convenient support that can be shaped into a host of attractive and varied morphologies. In this chapter, the study of CO oxidation catalyzed by mono-and bimetallic Au NPs over various silica supports is discussed in detail.

show abstract

Pollen-structured hierarchically meso/macroporous silica spheres with supported gold nanoparticles for high-performance catalytic CO oxidation

Cited by 9 publications

References 35 publications

Hierarchical Natural Pollen Cell-Derived Composite Sorbents for Efficient Atmospheric Water Harvesting

Hierarchical Natural Pollen Cell-Derived Composite Sorbents for Efficient Atmospheric Water Harvesting

Porous Silica-Coated Gold Sponges with High Thermal and Catalytic Stability

Silica-Supported Gold Nanocatalyst for CO Oxidation

Contact Info

Product

Resources

About