la courbe d'étalonnage peut être configurée en mesurant ou en entrant jusqu'à 10 étalons ou en entrant K et B facteursla courbe d'étalonnage peut être configurée en mesurant ou en entrant jusqu'à 10 étalons ou en entrant K et B facteurs

1. Author’s Accepted Manuscript
Flexible and Porous Cellulose Aerogels/Zeolitic
Imidazolate Framework (ZIF-8) Hybrids for
Adsorption Removal of Cr(IV) from Water
Shaoguo Bo, Wenjing Ren, Chao Lei, Yuanbo Xie,
Yurong Cai, Shunli Wang, Junkuo Gao, Qingqing
Ni, Juming Yao
PII: S0022-4596(18)30078-1
DOI: https://doi.org/10.1016/j.jssc.2018.02.022
Reference: YJSSC20126
To appear in: Journal of Solid State Chemistry
Received date: 25 December 2017
Revised date: 12 February 2018
Accepted date: 26 February 2018
Cite this article as: Shaoguo Bo, Wenjing Ren, Chao Lei, Yuanbo Xie, Yurong
Cai, Shunli Wang, Junkuo Gao, Qingqing Ni and Juming Yao, Flexible and
Porous Cellulose Aerogels/Zeolitic Imidazolate Framework (ZIF-8) Hybrids for
Adsorption Removal of Cr(IV) from Water, Journal of Solid State Chemistry,
https://doi.org/10.1016/j.jssc.2018.02.022
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2. Flexible and Porous Cellulose Aerogels/Zeolitic Imidazolate
Framework (ZIF-8) Hybrids for Adsorption Removal of Cr(IV)
from Water
Shaoguo Bo,a
Wenjing Ren,a
Chao Lei,a
Yuanbo Xie,a
Yurong Cai,a
Shunli Wang,b
Junkuo Gao,a
* Qingqing Nic
, Juming Yaoa
*
a
Institute of Fiber based New Energy Materials, The Key laboratory of Advanced Textile
Materials and Manufacturing Technology of Ministry of Education, College of Materials and
Textiles, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China.
b
Department of Physics, Center for Optoelectronic Materials and Devices, Zhejiang Sci-Tech
University, Hangzhou 310018, P. R. China
c
Department of Mechanical Engineering & Robotics, Shinshu University, 3-15-1 Tokida, Ueda,
Nagano 386-8576, Japan
Junkuo Gao
E-mail: jkgao@zstu.edu.cn
Juming Yao
E-mail: yaoj@zstu.edu.cn
*Corresponding author:

3. Abstract
The low cost of adsorption treatment of heavy metal ions in water has been
extensively studied. In this paper, we have demonstrated a facile method of
combining two emerging materials cellulose aerogels (CA) and metal–organic
frameworks (MOFs) into one highly functional aerogel to adsorption removal of
heavy metal ions from water, by entrapping MOF particles into a flexible and porous
CA. The resultant hybrid cellulose aerogels had a highly porous structure with zeolitic
imidazolate framework-8 (ZIF-8) loadings can reach 30 wt%. The hybrid cellulose
aerogels (named as ZIF-8@CA) show good adsorption capacity for Cr(Ⅵ
). The
adsorption process of ZIF-8@CA is better described by pseudo-second-order kinetic
model and Langmuir isotherm, with maximum monolayer adsorption capacity of 41.8
mg/g for Cr(Ⅵ
), whose adsorption capacity has greatly improved when compared with
a single CA or ZIF-8. Thus, such a flexible and durable hybrid cellulose aerogel is a
very prospective material for metal ions cleanup and industrial wastewater
purification.
Graphical abstract
Keywords: Metal-Organic Framework; Cellulose; Adsorption; Aerogel

4. 1. Introduction
With the rapid development of industry, litter emission has brought unprecedented
challenges to the environment. Industrial waste contains a large number of deadly
heavy metal ions and organic solvents, not only will cause serious pollution of the
environment and recipient water, but also on the surface water and groundwater
caused secondary pollution, cause the huge threat of the human and survival of
various creatures in the environment.[1-4]
Pollution in water has been causing a
worldwide attention ever since finding it harmful and/or disturbing.[5-8]
Unlike organic wastes, heavy metals can be accumulated in living tissues and
arenon-biodegradable. To solve this problem, various approaches including chemical
precipitation, coagulation, ion-exchange, and filtration have been applied successfully
to treat polluted water.[9-13]
However, approaches with higher efficiency, lower cost
and easier maintenance are still desirable. Adsorption and ion-exchange, have been
proposed for water purification.[14-15]
Among these techniques, adsorption is one of
the effective physical-chemical treatment methods for removing heavy metals from
aqueous solutions due to process and equipment is simple. Adsorption over porous
materials has risen to be one of the most promising approaches for water purification
during past decades.[16-19]
With high exposed surface area (inner as well as outer
surface) to be attached, porous materials such as zeolites,[20-23]
activated carbon,[24-27]
silica,[28]
polymeric materials[29-30]
and hybrid materials.[31]
Recently, there is a
growing interest in using cellulose for aerogel production, due to the fact that the
resulting aerogels reveal open porous structure with both high specific surface and

5. pore volume. The synergy of properties has prompted to cellulose aerogels as
promising candidates for versatile applications. Cellulose aerogel has a great many of
favorable properties such as hydrophobicity, biodegradability, strong ion-exchange
and gel-forming abilities, holding great promise for tissue engineering,[32–34]
drug
delivery,[35–37]
sewage treatment[38,39]
and as starting materials for carbon aerogels[40]
.
Apart from above advantages, pure CA still display some structural unsatisfactory
properties in weak mechanical strength, structural nonuniformity and fragile collapse
[41]
, which will limit their applications in many fields.
To handle this problem, an innovative technology that has gained attention is the
addition of reinforcing fillers, which has been considered to be an effective method
for improving the adsorption capacity and mechanical performance of aerogels. For
example, Xiong et al.[42-46]
discussed the roles of surfactants in different reaction
systems. Zhu et al.[47]
functionalized the MOF-cellulose hybrid aerogel using an insert
reaction with UIO-66 in liquid phase for adsorption capacity for metal ions. The
obtained MOF-cellulose hybrid aerogels were able to collect a wide range of organic
solvents and metal ions. Yang et al.[48]
prepared chemically cross-linked cellulose
nanocrystal (CNC) aerogels based on hydrazone cross-linking hydrazide and
aldehyde-functionalized cellulose nanocrystals, which can absorb dodecane of 72 g
g-1
.
Among popular fillers, ZIF-8 exhibits great potential due to its high binding
potential, high specific surface area and superior processability. As a result, the
ZIF-8@CA not only had highly homogeneous porous structure, but also exhibited

6. durable hydrophobicity. Especially, the hybrid cellulose aerogels could rapidly and
efficiently collect heavy metal ions both on the surface and bottom from water, and
exhibited excellent adsorption performances as well as good recyclability. And its
surface morphology and adsorption capacity for metal ions were investigated.
Scheme 1. Illustration of the routes employed for the growth of metal–organic
frameworks within cellulose aerogels as exemplified for ZIF-8 growth.
2. Experimental section
2.1. Materials
Cotton linter with a-cellulose content of more than 95% is provided by Heze
Sanmu Health Materials Co.Ltd. (Shandong, China). NaOH, Methanol, Urea,
N,N'-methylenebisacrylamide (MBA), Zincnitrate Hexahydrate (Zn(NO3)2•6H2O),
2-Methylimidazole, Chromic nitrate (Cr(NO3)3•9H2O) are purchased from Sinopharm
Chemical Co. Ltd. (Shanghai, China). All the chemical reagents are analytical grade,
and used without further purification.

7. 2.2. Synthesis of ZIF-8 nanoparticles
ZIF-8 nanoparticles were synthesized at room temperature following a slightly
modified method in the literature.[49]
Typically, 1.5g of Zn(NO3)2•6H2O and 3.3 g
2-methylimidazole were dissolved in 70 mL methanol, respectively. The two solutions
were then mixed under stirring at room temperature. The molar ratio of Zn2+
:
2-methylimidazole in the mixture was of 1:8. After 24 h of stirring, the product was
collected by centrifugation at 10000 rpm for 10 min, and then washed with deionized
water for several times. The obtained ZIF-8nanoparticles were dried in an oven at
80◦C for 24 h to remove residual water and then was kept in a desiccator for use.
2.3. Fabrication of cellulose aerogels
The cellulose aerogels (CA) were fabricated based on chemical cross-linking of
N,N'-methylenebisacrylamide (MBA). Briefly, desired cellulose was dispersed into
100 g of 7 wt% NaOH/12 wt% urea aqueous solution to form transparent solution
with a cellulose concentration of 4 wt% according to our previous reports.[50,51]
Subsequently, 0.6 g of MBA cross linkers was directly added into the cellulose
solutions at room temperature and stirred for 40 min to obtain homogeneous solution.
Then, the mixture was kept for 4 h to transform into cellulose hydrogels. The
cellulose hydrogels were washed with deionized water to remove any residues, and
finally freeze dried to obtain cellulose aerogels.
2.4. Fabrication of ZIF-8@CA composites
ZIF-8@CA composites were followed as indicated in Scheme 1. 1.5g Zn(NO3)2•6H2O
dispersed into 50 g solution with cellulose concentration of 4 wt%, under stirring

8. evenly at room temperature. Subsequently, 1.0 g of MBA cross linkers was directly
added into the Zn2+
@cellulose solutions at room temperature and stirred for 2 h to
obtain homogeneous solution. Then, the leftover as in the above steps to obtain
Zn2+
@cellulose aerogels. 20 g Zn2+
@cellulose aerogels were placed into 50 mL of
aqueous 2-methylimidazole (3.0 g) and soaked overnight. After washing 3 times with
fresh water, the resulting ZIF-8@CA was washed and freeze-dried.
2.5. Characterization
2.5.1 Analysis of structure and morphology.
Field-emission scanning electron microscopy (FESEM, Hitachi, Japan) was
employed to observe the morphologies of the aerogels and ZIF-8@CA after sputtering
with gold. The chemical structures of the aerogels and ZIF-8@CA was investigated
by FT-IR spectrometer (Nicolet 5700, Thermo Electron Corp.,USA), ranging from
4000 to 400 cm-1
at a resolution of 4 cm-1
using KBr disk method. The
Brunauer-Emmett-Teller (BET) method was used to calculate the specific surface
areas. The N2 adsorption-desorption isotherms at 77 K were measured on a
Micrometrics ASAP 2010 system to evaluate their pore structures. All the samples
were degassed at 120 °C for 2 h before the surface area measurements. The crystalline
nature of powders was characterized for phase identification and crystallite size
estimation under an X-ray powder diffractometer (XRD, ARL X’RA, Thermo
Electron Corp) with monochromatic Cu Kα (1.54056 Å) radiation (40 kV, 30 mA) in
the 2θ range of 5–60° at a scanning rate of 3° min. The thermal stability was
conducted using a thermogravimetric analyzer (TGA, Pyris Diamond I, Perkin-Elmer

9. Corporation). The samples with about 8–12 mg were heated from 30 to 800 ℃ at a
heating rate of 20 ℃/min under dynamic nitrogen atmosphere with a flow rate of 30
mL/min.
2.5.2 Estimation of density, pore volume and porosity
Density of the aerogels was calculated based on the ratio of its mass to volume. The
porosity of the aerogels was calculated based on the bulk density (ρb) and skeletal
density (ρs =1.528 g•cm-3
) of cellulose aerogels using eqn .[52]
Porosity(%) = 1- ρb/ρs (1)
The pore volume (Vp, milliliters of pores in 1 g of aerogels) of the aerogels was
calculated through the uptake of water in the aerogels. Water is a non-solvent for
cellulose, which only penetrates into the pores of the samples. Thus, Vp was
calculated according to the eqn
Vp = (Mwet - Mdry)/ρMdry (2)
where, Mwet is the weight of the samples immersed in water until it reached
swelling-equilibrium. Mdry is the weight of dry samples, and ρ is the density of water
(0.995 g mL-1
, 30℃). All samples were carried out in triplicate and then the average
values are considered.[53]
2.5.3 Kinetics of Ion Adsorption.
The efficiency of the absorbent was evaluated from pseudo-first-order,
pseudo-second-order to understand the mechanism of adsorption on ZIF-8@aerogels .
The rate constant of adsorption was determined from the pseudo-first-order equation,
which is generally expressed as[54]

10. ln (qe - qt) =ln qe - k1t (3)
where qe and qt are the adsorption capacities (mg/g) at equilibrium and time t,
respectively, and k1 is the rate constant for pseudo-first order adsorption. From the
plots of ln(qe − qt) versus t, the values of k1 and qe were determined.
The linear form of the pseudo-second order kinetic model is expressed as[55]
e
e
t q
t
q
k
q

 2
2
1
t
(4)
where k2 is the rate constant for second-order adsorption (g•mg−1
•min−1
) and is
determined from the linear plot of t/qt versus t.
The Langmuir, Freundlich and Dubinin-Redushckevich (D-R) adsorption isotherms
were used to describe the adsorption equilibrium over the entire concentration range
studied.
The saturated monolayer Langmuir isotherm can be represented as
e
e
m
e
bC
bC
q


1
q (5)
The constants qm and b are characteristics of the Langmuir equation and can be
determined from its linear form, represented by[56]
m
m
e
e bq
q
C
q
C 1
e

 (6)
where Ce (mg/L) is the equilibrium metal ion concentration, qe (mg/g) is the
amount of Cr(Ⅵ
) adsorbed on the adsorbent at equilibrium, and the parameters qm
(mg/g) and b (L/mg) are the Langmuir constants that relate qe for a complete
monolayer and energy of adsorption, respectively. These constants can be calculated
from the linear plot of Ce/qe versus Ce or 1/qe versus 1/Ce.

11. The Freundlich isotherm is expressed by the following equation:
n
e
F
e C
K
/
1
q  (7)
The linear logarithmic form of the Freundlich equation is as follows:
e
F
e C
n
K
nq ln
1
ln
l 
 (8)
where KF (mg/g) and 1/n indicate adsorption capacity and adsorption intensity,
respectively. The plot of ln qe versus ln Ce gives a straight line with a slope of 1/n and
an intercept of ln KF.
The D-R isotherm is employed to differentiate physical adsorption and chemical
adsorption[57]
,is expressed by the following equation:
)
exp(
q 2

k
Qm
e 
 (9)
)
1
1
(
ln
e
C
RT 

 (10)
Where ɛ is Polanyi potential, and k is the D-R constant, R is the universal gas
constant (8.314 J/K mol), T is the temperature in Kelvin (K). The mean energy (E) of
adsorption is calculated based on the k value by Eq. :
5
.
0
)
2
(
1
k
E  (11)
3. Results and discussion
Cellulose was selected as a growth matrix as it is inexpensive and non-toxic，forms
cellulose aerogels and its ensures abundant functionality is present from side chains
(e.g. NH2，COOH) for interaction with MOF building blocks. Furthermore, cellulose
is insoluble in water, it can be widely used in various water treatment.

12. 3.1. Characterization of ZIF-8@CA composites
3.1.1. PXRD measurements
The synthesis of the Zn(NO3)2•6H2O dispersed into the solution with cellulose
concentration of 4 wt%, MBA cross linkers to obtain Zn2+
@cellulose aerogels,
aqueous 2-methylimidazole soaked overnight and freeze-dried. Initial evidence of the
ZIF-8@CA samples was confirmed by PXRD (Fig. 1). The diffraction peak intensity
of ZIF-8 and ZIF-8@CA at (011), (002), (112) and (222) is basically indistinguishable.
(020) is a typical cellulose diffraction peak. The crystallinity in ZIF-8@CA is too low
to disappear. These phenomena indicate that the crystallinity of ZIF-8 in ZIF-8 @ CA
has not been destroyed. All of the diffraction peaks for the samples ZIF-8, CA and
ZIF-8@CA show that the sketch of the ZIF-8 crystal is well retained even after the
wrapped in CA.
Figure 1. PXRD pattern of a cellulose aerogel, pristine ZIF-8, and
ZIF-8@cellulose aerogels.
3.1.2. SEM measurements
The chemically cross-linked ZIF-8@CA were successfully prepared following a
facile process consisting of mixing and freeze-drying (as shown in Scheme 1). The

13. morphologies of the obtained ZIF-8@CA were observed by FESEM, and shown in
Fig. 2. Presents the FESEM images of ZIF-8 nanoparticles which reveal that the
particle sizes are of 20–40 nm (Fig. 2a), and shows the porous structure of the CA is
hierarchical with pore size in the range of 10-100 µm, and its three dimensional
network structure was constructed by filamentary cellulose matrix (Fig. 2b).
Importantly, the high ZIF-8 loading achieved and the porous structure of the CA
indicate that we have produced a novel hybrid material, which retains the favorable
properties of both ZIF-8 and CA (Fig. 2c).
Figure 2. SEM images of ZIF-8-containing cellulose aerogels. A)ZIF-8, B)
cellulose aerogels, C) cellulose aerogel with 30 wt% ZIF-8
3.1.3. TGA measurements
Thermogravimetric analysis (TGA) of freeze-dried ZIF-8@CA hybrids showed the
composite decomposes gradually over the temperature range 120–400 °C with a
decomposition profile reminiscent of pure CA, the residual part at 550 ℃ indicates a
ZIF-8 loading of 10-30 wt% (Fig. 3). The hybrid showed remarkable chemical
resistance to boiling alkaline water and organic solvents.

14. Figure 3. TGA curves for ZIF-8 powder, ZIF-8 containing cellulose aerogel with
different MOF loadings and cellulose aerogel without MOFs.
3.1.4. FTIR measurements
FTIR spectra were performed to the surface of ZIF-8@CA. Fig. 3 shows the FTIR
spectra of ZIF-8 and CA from 30 wt% concentration before and after load ZIF-8. In
the spectrum of raw CA (Fig. 3c), the characteristic peaks at 2888 cm-1
, 1645 cm-1
,
1545 cm-1
, 896 cm-1
are all the typical bands of CA molecules.[60]
The characteristic
peaks at 1430 cm-1
, 1310 cm-1
, 679 cm-1
are all the typical bands of ZIF-8
molecules(Fig. 3a). Obviously, ZIF-8@CA retains the characteristic peaks of both
ZIF-8 and CA (Fig. 4).
Fig. 4 FTIR spectra of ZIF-8(a), ZIF-8@ cellulose aerogels (b), cellulose aerogel

15. (c).
Compared with previously reported pristine ZIF-8, [58-59]the differences of IR,
TG and SEM are resulted from different methods of synthesis such as time,
temperature et al. In the paper Zn/Hmim molar ratio of 1:7, we use sodium hydroxide
instead of ammonium hydroxide and ZIF-8 preparation at room temperature. But the
peaks of powder XRD was identical. In addition, the presence of cellulose is also why
its characterization is not the same of IR and TG.
3.1.5. Morphology measurements
To further examine the effect of ZIF-8 concentration on the microstructure of the
aerogels, the density, porosity and the total volume of pores (Vp) of the cellulose
aerogels were estimated, and listed in Table 1. It was found that by increasing ZIF-8
concentration from 10 to 30 wt%, the density of ZIF-8@CA gradually increased,
while the porosity and the total pore volume decreased. But the ZIF-8@CA also
possessed an ultrahigh porosity of more than 95%, indicating light-weight and porous
ZIF-8@CA were successfully prepared.
Table 1. Physical properties of ZIF-8@CA from different ZIF-8 loading
concentrations
Sample Pore volume(cm3
g-1
) Porosity(%) Density(g cm-3
)
10 wt% ZIF-8 32.62 97.2 0.047
15 wt% ZIF-8 25.37 97.0 0.053
20 wt% ZIF-8 21.54 96.8 0.067
30 wt% ZIF-8 19.33 95.3 0.076

16. 3.2 Adsorption kinetics
The adsorption behaviors of pure CA and ZIF-8@CA for Cr(Ⅵ
) were shown in Fig.
5(a). Obviously, the adsorption rates were high at initial adsorption period, which
might be due to the interconnected porous structures and plentiful vacant sites of
aerogels. The equilibrium was reached within 120 min for Cr(Ⅵ
). Compared with
pure CA, 20.9 mg g-1
improvement of adsorption capacities were achieved and
reached up to 27.9mg g-1
, respectively, for Cr(Ⅵ
) when 30 wt% ZIF-8 was
incorporated. And the maximum adsorption capacities of ZIF-8 is 8.3 mg g-1
, the
adsorption capacities are significantly increased.
In order to evaluate the kinetic mechanism that controls the adsorption process, two
kinetic models, pseudo-first-order and pseudo-second-order, were applied to examine
the adsorption kinetics. Adsorption kinetics data were analyzed using Lagergren
pseudo-first-order model in Fig. 5(b) and pseudo-second-order model in Fig. 5(c).

17. Fig. 5. (a) Adsorption behaviors of pure CA and ZIF-8@CA for Cr(Ⅵ
). (b)
Pseudo-first-order kinetic plots of ZIF-8@CA. (c)Pseudo-second-order kinetic plots
of ZIF-8@CA.
Various parameters calculated from the plots of kinetic models are represented in
Table 2. The pseudo-second-order model best-fitted the experimental data with a
correlation coefficient value (R2
= 0.9993) close to 1, as compared to the
pseudo-first-order model (R2
= 0.9852). Moreover, the values of q calculated from the
pseudo-second-order model are closer to the experimental values, indicating that the
pseudo-second-order adsorption model is predominant.
Table 2. Kinetic parameters and experimental adsorption capacities for Cr(Ⅵ
) by
ZIF-8@CA.

18. Adsorbate
Qexp
(mg g-1
)
Pseudo-first-order model Pseudo-second-order model
Q1e, cal
(mg g-1
)
k1 R2
Q2e, cal
(mg g-1
)
k2×103
R2
Cr(Ⅵ
) 27.99 16.55 0.0266 0.9852 33.22 1.0471 0.9993
3.3 Adsorption isotherms for Cr(Ⅵ
) removal from water
The ability of such ZIF@CA to remove heavy metal ions from contaminated water
was preliminarily demonstrated by removal of chromium ion from water using the
sample ZIF@CA under a wide range of known chromium concentrations. As shown
in Table 3, the treatment of Cr(Ⅵ
) solution with ZIF@CA resulted in 90.79% removal
of Cr(Ⅵ
) ion when initial Cr(Ⅵ
) concentration was as high as 20ppm. More
importantly, the sample could still remove 99.74% of Cr(Ⅵ
) ion from the solution
even when initial Cr(Ⅵ
) concentration was as low as 1ppm.
Table 3. Influence of initial concentrations on the removal of ZIF-8@CA.
Concentrations (ppm) 1 10 20 40 60 80 100
Removal (%) 99.74 99.45 98.82 96.71 93.89 92.35 90.79
Adsorption of Cr(Ⅵ
) from aqueous solution using bare ZIF-8 and CA sample was
also carried out as a control experiment, and no detectable amount of Cr(Ⅵ
) ion was
adsorbed by the CA. Such high capacity of the ZIF-8@CA for Cr(Ⅵ
) adsorption can
be attributed to the N-pyridine densely populated on the inner surface of porous CA
with unique large specific surface areas and high density of adsorption sites.
To gain a better understanding of the mechanism of the heavy metal removal, the
ZIF@CA was characterized using the adsorption isotherm. By fitting the equilibrium

19. adsorption data with Langmuir, Freundlich and Dubinin-Redushckevich (D-R)
adsorption models are represented in Table 4, The value of R2
was found to be higher
for the Langmuir isotherm (0.994) compared to the Freundlich isotherm (0.974). In
addition, the values of q calculated from the Langmuir isotherm are quite close to the
experimental values (Figure 6b). The value RL = 0.2884-0.8530 lies between 0 and 1,
indicating a favorable adsorption process. Moreover, the value E(kj)=98 (>16) of
Dubinin-Redushckevich (D-R) isotherm indicates the adsorption process is chemistry
adsorption.
Fig. 6. (a) Influence of initial concentrations on the absorption capacity of
ZIF-8@CA. (b) Langmuir adsorption isotherm plots of ZIF-8@CA. (c) Freundlich
adsorption isotherm plots of ZIF-8@CA.
Table 4. Langmuir and Freundlich parameters for adsorption isotherms of

20. ZIF-8@CA.
Adsorbate
Langmuir Freundlich
Qmax(mg g-1
) KL(L mg-1
) R2
RL KF(L mg-1
) n R2
Cr(Ⅵ
) 41.84 0.0137 0.9944 0.2884-0.8530 1.227 1.5408 0.9743
4. Conclusions
In conclusion, we have demonstrated a facile way of combining two emerging
materials ZIF-8 and CA into one highly functional aerogel, was designed to be
adsorbents for adsorption of Cr(Ⅵ
) from its aqueous solutions. Obviously, the
adsorption capacities of cellulose aerogel for Cr(Ⅵ
) is significantly increased when
ZIF-8 is added, and the Langmuir maximum adsorption capacity reaches up to 41.84
mg g-1
. This kind of materials may also be extended to be used as air filters, sensors
and substrate supported catalysis.

21. Acknowledgement
This work is supported by the National Natural Science Foundation of China (51672251 and
51402261) and Science Foundation of Zhejiang Sci-Tech University (ZSTU) under Grant No.
13012138. J. G. acknowledges the financial support from the Zhejiang Provincial Top Key
Academic Discipline of Textile Science and Engineering and Qianjiang talents plan of Zhejiang
Province (QJD1502019).
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Highlights
1. A facile method of combining cellulose aerogels (CA) and metal-organic
frameworks (MOFs) into one highly functional aerogel was developed.
2. The resultant hybrid cellulose aerogels had a highly porous structure with zeolitic
imidazolate framework-8 (ZIF-8) loadings can reach 30 wt%.
3. The hybrid composite showed high adsorption removal of heavy metal ions from
water.