Graphene Oxide as Support for Layered Double Hydroxides: Enhancing the CO₂ Adsorption Capacity

Abstract

Layered double hydroxides (LDHs) show great potential as CO 2 adsorbent materials, but require improvements in stability and CO 2 adsorption capacity for commercial applications. In the current study, graphene oxide provides a light-weight, chargecomplementary, two-dimensional (2D) material that interacts effectively with the 2D LDHs, in turn enhancing the CO 2 uptake capacity and multicycle stability of the assembly. As a result, the absolute capacity of the LDH was increased by 62% using only 7 wt % graphene oxide (GO) as a support. The experimental procedure for the synthesis of the materials is based on a direct precipitation of the LDH nanoparticles onto GO followed by a structural and physical characterization by electron microscopy, X-ray diffraction, thermogravimetric analysis, and Brunauer−Emmett− Teller (BET) surface area measurements. Detailed titration confirmed the compatibility of the surface chemistry. After thermal decomposition, mixed metal oxides (MMOs) are obtained with the basic sites required for the CO 2 adsorption. A range of samples with different proportions of GO/MMO were prepared, fully characterized, and correlated with the CO 2 sorption capacity, established via TGA.

Graphene-oxide-supported CuAl and CoAl layered double hydroxides as enhanced catalysts for carbon-carbon coupling via Ullmann reaction

“…When combining LDH with GO, the heat and mass transfers during a reaction can be greatly improved. As previously observed in our group [22] GO can also offer the mechanical strength that allows a better stability of the catalyst under operation conditions, as well as facilitate the recovery and reuse of the catalyst. In this regard, there is one previous study that combines LDH and GO as heterogeneous catalyst and probes the enhancement of the catalytic activity mainly attributed to the higher metal dispersion and smaller size of deposited nanoparticles [23].…”

Preparation and analysis of multi-layered hybrid nanostructures

“…The LDH can absorb inorganic as well as organic anions, which make them attractive materials for technological applications in different areas (Olfs et. al., 2009).Recently, graphene decorated layered metal hydroxides likeLDH(with different metal) compositions were studied in order to diminish their stacking interactions and to limit the aggregation ingraphenenanosheets(Garcia- Gallastegui et al 2012;Latorre-Sanchez et al, 2012;Tang et al, 2012;Wen et al, 2013;Lonkar et al, 2015).In the present study, we report a simple method for preparation of multifunctional hybrid NS of Mg-Al-LDH@GO by bath ultra-sonication technique.Multi-layeredhybrids of LDH@GO were analyzed by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Fieldemission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), Elemental analysis (EDX) and thermo gravimetric analysis (TGA)to investigate their functional composition, crystalline nature, layered surface morphology, elemental analysis and thermal behavior.…”

“…LDH@GObased hybrid NSwereeasily prepared by one-pot microwave-assisted synthesis approach (Garcia- Gallastegui et al 2012;Tang et al, 2012;Wen et al, 2013;Lonkar et al, 2015). GO was prepared from graphite average particle size of < 20 μmby a modified Hummers method (Yadav et.…”

Environmental applications using graphene composites: water remediation and gas adsorption

“…Recently, a low temperature method for the preparation of LDH-GO hybrids by using a layer-by-layer self-assembly process of positively charged Mg-Al LDH onto negatively charged GO has been reported. 150 In this process GO acts as a support that improves the nucleation of active sites which upon activation form mixed metal oxides (MMOs) i.e. the basic sites required for CO 2 adsorption.…”