Graphene Oxide Modified UiO-66 Based Metal Organic Framework Gel: Preparation and Efficient Toluene Adsorption Performance

doi:10.15541/jim20250265

Abstract

Abstract:

Volatile organic compounds (VOCs), particularly aromatic hydrocarbons such as toluene, pose significant threats to the environment and human health due to their high volatility and biological toxicity. Traditional metal- organic frameworks (MOFs) are primarily microporous, and their trade-off between adsorption capacity and molecular transport efficiency has driven development of more advanced material systems. In this work, graphene oxide (GO) doped metal-organic framework gels (MOGs) based on UiO-66 were developed, leveraging the synergistic modification effect of GO. The π-conjugated structure of GO enhanced π-π interactions with toluene molecules, while its abundant oxygen-containing functional groups facilitated competitive coordination with metal nodes, leading to exposure of additional Lewis acid sites and thereby enhancing metal-π interactions. Experimental results demonstrated that UG-1 with a mass ratio of GO to ZrCl₄ at 1 : 100 exhibited a breakthrough adsorption capacity of 77.4 mg/g in dynamic adsorption experiments and a saturated capacity of up to 1245.5 mg/g in static tests, outperforming both UiO66 MOF and UiO66 MOG materials. In conclusion, this study elucidates multiple regulatory mechanisms of GO incorporation in modulating pore structure and host-guest interactions, providing a new theoretical basis and practical guidance for designing efficient and recyclable VOC adsorbents.

Key words: graphene oxide, metal-organic framework, volatile organic compound, hierarchical pore structure

CLC Number:

TQ174

ZHU Kaihuang, YANG Shijie, LI Xinge, SONG Guanqing, SHI Gansheng, WANG Yan, REN Xiaomeng, LU Yao, XU Xinhong, SUN Jing. Graphene Oxide Modified UiO-66 Based Metal Organic Framework Gel: Preparation and Efficient Toluene Adsorption Performance[J]. Journal of Inorganic Materials, 2026, 41(4): 519-526.

Figures/Tables 11

Fig. 1 Experiment flow diagram of the toluene breakthrough adsorption

Fig. 2 (a) XRD patterns and (b) Raman spectra of UiO66 MOF, UiO66 MOG, UG-1, and UG-2

Fig. 3 (a) N2 adsorption-desorption isotherms, and pore size distribution curves in the ranges of (b) 0-10 nm and (c) 10-30 nm of UiO66 MOF, UiO66 MOG, UG-1, and UG-2 with inset in (b) showing magnified view for the 0.5-3 nm range

Table 1 Specific surface area and pore structure parameters of UiO66 MOF, UiO66 MOG and UG-x

Sample	S_BET/(m²·g^-1)	S_micro/(m²·g^-1)	S_meso/(m²·g^-1)
UiO66 MOF	1020.9	945.2	75.7
UiO66 MOG	909.8	511.1	398.7
UG-1	973.8	536.8	437.0
UG-2	1062.4	749.5	312.9

Fig. 4 (a) Toluene vapor adsorption isotherms and (b) saturated toluene adsorption capacities of UiO66 MOF, UiO66 MOG, UG-1, and UG-2 with inset in (a) showing adsorption isotherms in a low-pressure region p/p0=0-0.05

Table 2 Toluene saturation adsorption capacities of various adsorbents[2,18 -22]

Adsorbent	p/p₀	Temperature/K	q/(mg·g^-1)
AC^[18]	1.0	298	530.4
Silica gel^[18]	1.0	298	437.4
UiO-66-NH₂@ABP^[19]	0.9	298	178.9
MIL-125-NH₂^[2]	0.94	298	293
MIL-100(Fe)_A2^[20]	1.0	298	523.3
HKUST-1^[21]	0.9	298	516
MSN-100^[22]	0.94	298	461
UG-1	1.0	298	1245.5

Fig. 5 Dynamic breakthrough curves for toluene adsorption within (a) 800 and (b) 250 min, and (c) equilibrium toluene adsorption capacities of UiO66 MOF, UiO66 MOG and UG-1

Table 3 Breakthrough time, equilibrium time and equilibrium adsorption capacities of UiO66 MOF, UiO66 MOG and UG-1

Sample	t_b/min	t_e/min	q/(mg·g^-1)
UiO66 MOF	200	580	59.7
UiO66 MOG	200	590	53.2
UG-1	240	750	77.4

Fig. 6 TPD curves of toluene for UiO66 MOF, UiO66 MOG and UG-1

Fig. 7 In-situ DRIFTS spectra of toluene adsorption for (a) UiO66 MOG and (b) UG-1 Colorful figures are available on website

Fig. 8 NH3-TPD curves of UiO66 MOG and UG-1

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