Encapsulating Perovskite Quantum Dots in Iron-Based Metal–Organic Frameworks (MOFs) for Efficient Photocatalytic CO2 Reduction

Article abstract of DOI:10.1002/anie.201904537

Improving the stability of lead halide perovskite quantum dots (QDs) in a system containing water is the key for their practical application in artificial photosynthesis. Herein, we encapsulate low-cost CH₃NH₃PbI₃ (MAPbI₃) perovskite QDs in the pores of earth-abundant Fe-porphyrin based metal organic framework (MOF) PCN-221(Fe_x) by a sequential deposition route, to construct a series of composite photocatalysts of MAPbI₃?PCN-221(Fe_x) (x=0–1). Protected by the MOF the composite photocatalysts exhibit much improved stability in reaction systems containing water. The close contact of QDs to the Fe catalytic site in the MOF, allows the photogenerated electrons in the QDs to transfer rapidly the Fe catalytic sites to enhance the photocatalytic activity for CO₂ reduction. Using water as an electron source, MAPbI₃?PCN-221(Fe_0.2) exhibits a record-high total yield of 1559 μmol g^?1 for photocatalytic CO₂ reduction to CO (34 %) and CH₄ (66 %), 38 times higher than that of PCN-221(Fe_0.2) in the absence of perovskite QDs.

Full text of DOI:10.1002/anie.201904537

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Accepted Article
Title: Encapsulating Perovskite Quantum Dots in Iron-Based Metal-
Organic Frameworks for Efficient Photocatalytic CO2 Reduction
Authors: Li-Yuan Wu, Yan-Fei Mu, Xiao-Xuan Guo, Wen Zhang, Zhi-
Ming Zhang, Min Zhang, and Tong-Bu Lu
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To be cited as: Angew. Chem. Int. Ed. 10.1002/anie.201904537
Angew. Chem. 10.1002/ange.201904537
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10.1002/anie.201904537
Angewandte Chemie International Edition
COMMUNICATION
Encapsulating Perovskite Quantum Dots in Iron-Based Metal-
Organic Frameworks for Efficient Photocatalytic CO2 Reduction
Li-Yuan Wu, Yan-Fei Mu, Xiao-Xuan Guo, Wen Zhang, Zhi-Ming Zhang, Min Zhang,* and Tong-Bu Lu*
Abstract: Improving the stability of lead halide perovskite quantum
dots (QDs) in a reaction system containing water is the key point for
their practical applications in artificial photosynthesis. Herein, we
encapsulate low-cost CH3NH3PbI3 (MAPbI3) perovskite QDs in the
pores of earth-abundant Fe-porphyrin based metal organic
framework of PCN-221(Fex) by a sequential deposition route, to
construct a serious of composite photocatalysts of MAPbI3@PCN-
221(Fex) (x = 0~1). Benefiting from the protection of the framework
of PCN-221(Fex), the composite photocatalysts exhibit much
improved stability in reaction systems containing water. In addition,
due to the close contact of QDs to the efficiently catalytic site of Fe
in PCN-221(Fex), the photogenerated electrons in the confined QDs
can swift transfer to the Fe catalytic sites to remarkably enhance the
photocatalytic activity of PCN-221(Fex) for CO2 reduction. Using
water as an electron source, MAPbI3@PCN-221(Fe0.2) exhibits a
record-high total yield of 1559 μmol g−1 for photocatalytic CO2
reduction to CO (34%) and CH4 (66%), 38 times higher than that of
PCN-221(Fe0.2) in the absence of perovskite QDs. Our study
provides an effective strategy for improving the stability and charge
separation efficiency of perovskite QDs, promoting their practical
applications in photocatalytic CO2 reduction.
photocatalytic CO2 reduction, LHP QDs have been
demonstrated to be capable of converting CO2 to CO and
CH4.[27] Loading LHP QDs on graphene oxide[26] or g-C3N4[24] can
facilitate the charge separation, bringing forth improved catalytic
performance for CO2 reduction. However, the insufficient stability
of LHP QDs and the lack of effective catalytic sites limit their
photocatalytic performance for CO2 reduction. To overcome
these obstacles, we encapsulated LHP QDs of CH3NH3PbI3
(MAPbI3) in the pores of Fe-porphyrin based metal organic
frameworks (MOFs) of PCN-221(Fex) to construct a serious of
composite photocatalysts of MAPbI3@PCN-221(Fex) for visible-
light-driven CO2 reduction (x = 0~1). Our strategy is based on
the following considerations: 1) Owing to the confinement effect
of porous MOF, QDs with ultra-small size and homogeneous
distribution can be generated in the pores of MOF.[34−37] 2) Apart
from good catalytic activity of MOFs for the conversion of CO2,[34,
38−41]
the framework of MOFs can improve the stability of LHP
QDs.[37,42] 3) The close contact of LHP QDs to the catalytic
active center in MOFs can shorten the charge transfer distance,
thus enhancing the photo-induced charge separation efficiency
of LHP QDs and catalytic activity of MOFs. As expected, all the
MAPbI3@PCN-221(Fex) composite photocatalysts exhibit much
enhanced photocatalytic stability and activity for CO2 reduction
compared with pure QDs and corresponding PCN-221(Fex),
getting record-high stability (over 80 h) and yield for the
productions of CO and CH4 (1559 μmol g−1).
Direct light-driven CO2 reduction to high-value added chemical
feedstocks or fuels using efficient catalysts is one of fascinating
technologies, in response to slowly but inevitably exhausted
fossil fuels, as well as the climate-changing induced by CO2
greenhouse gas emission.[1−6] In above artificial photosynthesis
process, a crucial challenge is to design efficient and low-cost
catalysts and photosensitizers. In this context, a series of
efficient photocatalysts based on earth-abundant elements such
as Fe,[7−9] Co[10−13] and Ni[14,15] have been developed.[16]
Meanwhile, some semiconductor nanocrystals (NCs) have been
pursued as photosensitizers, owing to their large extinction
coefficients and flexibly adjustable thermodynamic and optical
properties with the regulation of particle sizes.[17−20] In this regard,
lead halide perovskite (LHP) NCs are ordinarily endowed with
high defect tolerance and long photogenerated carrier lifetime,
triggering their widespread applications in photovoltaic and
optoelectronic devices.[21−23]
Most recently, LHP quantum dots (QDs) have also been
actively pursued as catalysts in photocatalytic fields.[24−33] In
Scheme 1. Schematic illustrations for the synthesis of (a) PCN-221(Fex), and
(b) MAPbI3 QDs encapsulated in the pores of PCN-221(Fex) by a sequential
deposition route (MAI = CH3NH3I).
[*]
L.Y. Wu, Y.F. Mu, X.X. Guo, Dr. W. Zhang, Prof. Z.M. Zhang, Prof.
M. Zhang, Prof. T.B. Lu
Institute for New Energy Materials and Low Carbon Technologies,
School of Chemistry and Chemical Engineering,
Tianjin University of Technology
As depicted in Scheme 1a, the pristine PCN-221(Fex)
MOFs with different Fe contents (x = 0, 0.2, 0.4, 0.6, 0.8, 1)
were synthesized according to the reported method,[43] and the
details are described in the Supporting Information. X-ray
powder diffraction (XRD) measurements show that the XRD
patterns of PCN-221(Fex) are well agree with the simulated
pattern of PCN-221 (Figure S1), indicating that the coordination
of iron atom to porphyrin ring does not change the crystal
Tianjin 300384, China
E-mail: zm2016@email.tjut.edu.cn; lutongbu@tjut.edu.cn
Supporting information for this article is given via a link at the end of
the document.
This article is protected by copyright. All rights reserved.

10.1002/anie.201904537
Angewandte Chemie International Edition
COMMUNICATION
structure of PCN-221. Considering the fast reaction kinetics of
nucleation and growth processes for LHP QDs owing to their
ionic crystal feature,[44] we herein performed a sequential
deposition route to encapsulate the MAPbI3 QDs into the pores
of PCN-221(Fex), as illustrated in Scheme 1b. The as-prepared
PCN-221(Fex) was first immersed in a solution of PbI2. The
resulting PbI2@PCN-221(Fex) was rinsed with N,N-
dimethylformamide/ethanol and ethanol to remove the residual
PbI2 on the surface of PCN-221(Fex). PbI2@PCN-221(Fex) was
then immersed in a MAI ethanol solution for 10 min to generate
the final MAPbI3@PCN-221(Fex) composite photocatalysts after
rinsing with ethanol. The actual Fe contents in MAPbI3@PCN-
221(Fex) (x = 0.2, 0.4, 0.6, 0.8, 1) determined by inductively
coupled plasma mass spectrometry (ICP-MS) analysis are 0.15,
0.34, 0.55, 0.78 and 0.97, respectively.
(Figure S2), which can be ascribed to their small sizes confined
in the pores of PCN-221(Fe0.2). While the IR spectrum of
MAPbI3@PCN-221(Fe0.2) shows the characteristic absorption
peaks of MAPbI3 QDs at 1466 and 906 cm−1 (Figure S3), which
can be assigned to the symmetric bending vibration of NH3 and
+
rocking vibration of CH3-NH3 , respectively,[45] indicating the
existence of MAPbI3 QDs in the pores of PCN-221(Fe0.2). The
TEM image reveals that the average size of MAPbI3 QDs in
PCN-221(Fe0.2) is approximately 1.8 nm (Figure 1a), which
matches the pore size of PCN-221(Fe0.2) (~ 2 nm).[46] HRTEM
image of MAPbI3@PCN-221(Fe0.2) shows the lattice spacing of
MAPbI3 QDs being 0.31 nm (Figure 1b), which is consistent with
that of MAPbI3 bulky sample.[47] The elemental mapping of
MAPbI3@PCN-221(Fe0.2) (Figures 1d-1i) indicates that MAPbI3
QDs are uniformly dispersed in the pores of PCN-221(Fe0.2). All
the above results demonstrate the MAPbI3@PCN-221(Fe0.2
)
composite catalyst was successfully synthesized. The N2
adsorption isotherms for PCN-221(Fe0.2) before and after the
QDs encapsulation indicate 20% of the pores in the MOF are
occupied by MAPbI3 QDs (Figure S4).
The photocatalytic CO2 reduction reactions were performed
in CO2-saturated ethyl acetate solution containing small amount
of water, under 300 W Xe-lamp irradiation with a 400 nm filter.
For all the evaluated PCN-221(Fex) and MAPbI3@PCN-221(Fex)
photocatalysts, the main reduction products are CO and CH4 in
the cases of MOFs containing Fe, and CO is the main reduction
product for PCN-221 and MAPbI3@PCN-221 without Fe (Figure
2a). No H2 and liquid products such as HCOOH and CH3OH
were detected for all the evaluated photocatalytic systems. To
further confirm the origin of CO and CH4 products, we first
performed control experiments by using N2 gas to replace CO2
under the same condition. Almost no CO and CH4 were
produced, as depicted in Figure S5. In addition, 13CO2 isotope
trace experiment shows that the major mass spectrum signals
with m/z values of 29 (13CO) and 17 (13CH4) can be clearly
observed (Figure S6), indicating that both CO and CH4 originate
from the photocatalytic CO2 reduction instead of photo-oxidation
of ethyl acetate.
As presented in Figure 2a and Table S1, in the cases of
pristine PCN-221(Fex) with various contents of Fe as
photocatalysts, the CO2 reduction activity enhances along with
the increase of Fe content, owing to the increase of Fe catalytic
sites. Moreover, the selectivity of CH4 formation also increases
along with the increase of Fe content in PCN-221(Fex) (Figure
2a), which may originate from the increased concentration of CO
induced by the enhanced activity, indicating that CO is a key
intermediate in the process of CH4 formation.[8] This speculation
has been further demonstrated by the photocatalytic experiment
in CO-saturated ethyl acetate/water solution, where CH4 is the
only detected product. However, all the cases of pristine PCN-
221(Fex) photocatalysts generate very low yields for both CO
and CH4. For the most efficient catalyst system based on pristine
PCN-221(Fe), the yields of CO and CH4 are only 13 and 38 μmol
g−1, respectively, after 25 h of irradiation. After that time, the
PCN-221(Fex) photocatalysts were decomposed and lost the
catalytic activity.
Figure 1. (a) TEM image of MAPbI3@PCN-221(Fe0.2), the black dots
belonging to MAPbI3 QDs, and the inset is particle size distribution of MAPbI3
QDs. (b) HRTEM image with lattice spacing of MAPbI3 QDs in MAPbI3@PCN-
221(Fe0.2). (c) TEM image, and (d-i) elemental mapping for MAPbI3@PCN-
221(Fe0.2).
MAPbI3@PCN-221(Fe0.2) was chosen as a typical sample to
analyse the composition and structure of in-situ generated
MAPbI3 QDs within the pores of PCN-221. The results of XRD
measurements reveal that the formation of MAPbI3 QDs in the
pores of PCN-221(Fe0.2) does not disturb the framework of PCN-
221(Fe0.2) (Figure S2). The XRD characteristic peaks of MAPbI3
QDs were not observed in MAPbI3@PCN-221(Fe0.2) composite
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10.1002/anie.201904537
Angewandte Chemie International Edition
COMMUNICATION
600
221(Fex), resulting in reduced number of transferred electrons
from MAPbI3 QDs to Fe catalytic sites along with the increase of
Fe content in PCN-221(Fex).
(a)
CH4
500
CO
400
300
200
100
0
Moreover, it is excited to note that the MAPbI3@PCN-
221(Fex) composite photocatalysts display an obvious
improvement of stability compared with relatively stable PCN-
221(Fex), in which MAPbI3@PCN-221(Fex) photocatalysts
display linear productions of CO and CH4 with a time over 80 h,
as observed in Figures S5a and S5b, while PCN-221(Fex)
photocatalysts can only be stable within 30 h (Figures S5c and
S5d), after that time they decompose and lose the catalytic
activity. Meanwhile, the stability of MAPbI3 QDs in
MAPbI3@PCN-221(Fex) is also much more stable than those of
reported LHP QDs based photocatalysts for CO2 reduction.[24-27]
Thus MAPbI3@PCN-221(Fex) composite photocatalysts display
significantly enhanced yields for CO2 reduction, 25~38 times
higher than those of corresponding PCN-221(Fex) in the
absence of perovskite QDs (Figure 2b), in which MAPbI3@PCN-
221(Fe0.2) gets a record-high yield of 1559 μmol g−1 for
photocatalytic CO2 reduction to CO (34%) and CH4 (66%), 38
times higher than that of pristine PCN-221(Fe0.2) (41 μmol g−1).
To the best of our knowledge, this is the highest value among
diverse perovskite QDs based catalysts for photocatalytic CO2
reduction up to now. The results of XRD measurements of
)
)
)
)
)
)
)
)
)
)
0.4
0.6
0.8
0.2
0.4
0.8
0.2
0.6
Fe
Fe
(
(
Fe
Fe
Fe
(
Fe
Fe
Fe
(
Fe
Fe
(
(
(
(
(
(
CN-221
PCN-221
@P
CN-221
3
PCN-221
CN-221
CN-221
CN-221
CN-221
PCN-221
PCN-221
PCN-221
PCN-221
@P
3
@P
3
@P
3
@P
3
@P
3
MAPbI
MAPbI
MAPbI
MAPbI
MAPbI
MAPbI
2000
1600
1200
800
400
0
(b)
CH4
CO
)
)
)
)
)
)
)
)
)
)
MAPbI3@PCN-221(Fe0.2
)
and
PCN-221(Fe0.2
)
after
0.2
0.6
0.2
0.6
0.4
0.4
0.8
0.8
Fe
Fe
(
(
Fe
Fe
(
Fe
Fe
Fe
Fe
Fe
Fe
(
(
(
(
(
(
(
photocatalytic reaction show that the pattern of MAPbI3@PCN-
221(Fe0.2) agrees well with that of simulated PCN-221 (Figure
CN-221
PCN-221
@P
CN-221
3
PCN-221
CN-221
CN-221
CN-221
CN-221
PCN-221
PCN-221
PCN-221
PCN-221
@P
3
S7), indicating the crystal structure of MAPbI3@PCN-221(Fe0.2
)
@P
3
@P
3
@P
3
@P
3
MAPbI
can retain its integrity after the photocatalytic reaction. While
PCN-221(Fe0.2) becomes amorphous (Figure S7), indicating it
totally decomposes after the photocatalytic reaction. The
improved stability induced by the insertion of MAPbI3 QDs into
the pores of PCN-221(Fe0.2) may be attributed to the competitive
light absorption between MAPbI3 QDs and PCN-221(Fe0.2),
which can decrease the photodegradation of PCN-221(Fe0.2).[48]
To identify the electron source for the reduction of CO2 to
CO and CH4, the H218O isotope trace experiment was carried out
in a CO2-saturated ethyl acetate/H218O solution containing
MAPbI3@PCN-221(Fe0.2) photocatalyst, and the major mass
spectrum signal with a m/z value of 36 (18O2) can be observed
(Figure S8). In addition, the amount of oxygen generated in CO2-
saturated ethyl acetate/water solution using MAPbI3@PCN-
221(Fe0.2) as a photocatalyst is close to one fourth of total
amount of electron consumption (eamount) for the generation of
CH4 and CO (Figure S9). The above results clearly demonstrate
that the electron source for the reduction of CO2 originates from
the oxidation of water rather than the oxidation of ethyl acetate.
To further exclude the possibility of the electron source coming
from the oxidation of ethyl acetate, a more stable solvent of
acetonitrile was used to replace ethyl acetate for the above
photocatalytic reaction under the same conditions, and similar
amounts of CO, CH4 and O2 were also detected (Figure S10). All
the above results firmly demonstrate that the electron source for
the CO2 reduction comes from the water oxidation. Our results
make a great step forward practical application in artificial
photosynthesis using water as an electron source.
MAPbI
MAPbI
MAPbI
MAPbI
MAPbI
Figure 2. (a) The yields for CO2 reduction to CH4 and CO with PCN-221(Fex)
and MAPbI3@PCN-221(Fex) as photocatalysts in the CO2-saturated ethyl
acetate/water solution after (a) 25 h, and (b) 80 h of irradiation under 300 W
Xe-lamp, with the light intensity of 100 mW cm−2
.
Under the same irradiation time of 25 h, MAPbI3@PCN-221
without Fe also displays little photocatalytic activity for CO2
reduction (Figure 2a). While the composite photocatalysts
containing both MAPbI3 QDs and Fe exhibit significant
improvement of photocatalytic activity for CO2 reduction,
generating remarkably enhanced yields for both CO and CH4,
suggesting Fe is the vital catalytic site for photocatalytic CO2
reduction. Particularly, MAPbI3@PCN-221(Fe0.2) exhibits the
highest photocatalytic activity, achieving 104 μmol g−1 of CO and
325 μmol g−1 of CH4. The calculated value for electron
consumption rate (Relectron = (2Yield CO + 8Yield CH4)/25 h) is
112 μmol g−1 h−1, which is about 31 and 8 times larger than
those of corresponding pristine PCN-221(Fe0.2) and PCN-
221(Fe) counterparts, respectively. The values of Relectron for
MAPbI3@PCN-221(Fex) (53 ~ 112 μmol g−1 h−1) are also much
larger than those of composite photocatalysts of LHP QDs with
MOFs coating (15 ~ 30 μmol g−1 h−1),[25] which can be ascribed
to the close contact between MAPbI3 QDs and Fe catalytic sites.
As shown in Figure 2a, the values of Relectron and the selectivity
of CH4 generation gradually decrease along with the increase of
Fe content in MAPbI3@PCN-221(Fex), which may be ascribed to
the competitive light absorption between MAPbI3 QDs and PCN-
To deep understand the origin of the significantly enhanced
efficiency for photocatalytic CO2 reduction induced by
capsulation of MAPbI3 QDs into the pores of PCN-221(Fex), we
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10.1002/anie.201904537
Angewandte Chemie International Edition
COMMUNICATION
first inspected the light-harvesting capacity of MAPbI3@PCN-
221(Fe0.2) by recording the electronic absorption spectra of
in PCN-221(Fe0.2) with respect to PCN-221 without Fe ion, with
the short time constant τ1 for electron transfer being only ~ 0.1
ns (Table S2), indicating the occurrence of swift electron transfer
from porphyrin groups to Fe catalytic sites after photo-excitation.
Moreover, MAPbI3@PCN-221(Fe0.2) also displays a fast PL
decay process compared with PCN-221(Fe0.2) (Figure 3d),
suggesting the time constant of electron transfer from MAPbI3
QDs to Fe catalytic sites is comparable to that from porphyrin
groups to Fe catalytic sites in PCN-221(Fe0.2) (Table S2), which
can be ascribed to the close contract between MAPbI3 QDs and
Fe catalytic sites.
MAPbI3@PCN-221(Fe0.2
) and PCN-221(Fe0.2) powders. As
shown in Figure S11, the absorption intensity of MAPbI3@PCN-
221(Fe0.2) is much higher than that of PCN-221(Fe0.2) owing to
the high absorption coefficient of MAPbI3 QDs. In addition, the
flat-band potentials (corresponding to the conduction band edge)
for PCN-221(Fe0.2) and MAPbI3@PCN-221(Fe0.2) obtained from
the Mott-Schottky plots are −1.00 V and −1.25 V (vs NHE),
respectively (Figures 3a and 3b), indicating the photoexcited
electrons in PCN-221(Fe0.2) have enough driving force to reduce
CO2 to CO (−0.52 V vs NHE) or CH4 (−0.24 V vs NHE), and the
photoexcited electron transfer from MAPbI3 QDs to PCN-
221(Fe0.2) is thermodynamically permissible.
In
summary,
MAPbI3@PCN-221(Fex)
composite
photocatalysts have been successfully synthesized based on a
sequential deposition route to control the growing rate of MAPbI3
QDs. Encapsulating the MAPbI3 QDs in the pores of PCN-
221(Fex) does not change their crystal structures, but brings
forth an obviously enhanced light-harvesting capacity. Steady
state and time-resolved photoluminescence experiments reveal
that the photogenerated electrons in the encapsulated MAPbI3
QDs can swift transfer to Fe catalytic sites, achieving efficient
charge separation between the perovskite QDs and Fe-
porphyrin based MOF. The resultant composite photocatalyst of
MAPbI3@PCN-221(Fe0.2) exhibits extrimely high photocatalytic
activity for the reduction of CO2 to CO and CH4, 38-fold higher
than that of corresponding PCN-221(Fe0.2), using water as a
sacrificial reductant. Moreover, the MAPbI3 QDs encapsulation
can significantly improve the stability of both LHP QDs and
PCN-221(Fex). Our study will boost the development of more
efficient artificial photosynthesis system based on cheap
photosensitizers and earth-abundant catalysts, to reduce CO2
into chemical feedstocks or fuels using water as an electron
source and driven by visible light.
a)
b)
PCN-221(Fe0.2
)
MAPbI3@PCN-221(Fe0.2)
1.2
0.9
0.6
0.3
0.0
4
2
0
1.00 V
1.25 V
-1.5
-1.0
-0.5
0.0
-3.0
-1.5
0.0
1.5
Potential [V vs. NHE]
Potential [V vs. NHE]
d)
c)
1.0
0.5
0.0
PCN-221
PCN-221
PCN-221(Fe0.2
PCN-221(Fe0.2
MAPbI3@PCN-221
MAPbI3@PCN-221(Fe0.2
)
)
MAPbI3@PCN-221
80
40
0
)
MAPbI3@PCN-221(Fe0.2
)
550
600
650
700
750
0
2
4
t [ns]
 [nm]
Figure 3. (a) Mott−Schottky plots of MAPbI3@PCN-221 and (b)
MAPbI3@PCN-221(Fe0.2). (c) Steady state photoluminescence spectra of
PCN-221, PCN-221(Fe0.2), MAPbI3@PCN-221 and MAPbI3@PCN-221(Fe0.2).
(d) Time-resolved photoluminescence decays of PCN-221, PCN-221(Fe0.2),
Acknowledgements
This work was financially supported by National Key R&D
Program of China (2017YFA0700104), Natural Science
Foundation of Tianjin City (17JCJQJC43800), NSFC (21790052,
21722104, and 21702146), and the 111 Project (D17003).
MAPbI3@PCN-221 and MAPbI3@PCN-221(Fe0.2) with ET519LP as long-
wavelength pass filter, after excitation at 375 nm.
Steady state photoluminescence (PL) measurements were
further carried out to evaluate the photoexcited electron transfer
processes in MAPbI3@PCN-221(Fex) composite system. As
presented in Figure 3c, PCN-221 shows two peaks around 655
and 712 nm, which originate from the PL of porphyrin groups in
PCN-221. The encapsulation of MAPbI3 QDs in PCN-221 leads
to a new PL peak at 610 nm, which can be assigned to the
luminescence of MAPbI3 QDs. However, the intensities of the
Conflict of interest
The authors declare no conflict of interest.
Keywords: metal organic framework • perovskite quantum dot •
Fe-based catalyst • photocatalysis • CO2 reduction
above peaks are dramatically decreased in both PCN-221(Fe0.2
)
[1]
[2]
J. H. Montoya, L. C. Seitz, P. Chakthranont, A. Vojvodic, T. F. Jaramillo,
J. K. Nørskov, Nat. Mater. 2017, 16, 70−81.
and MAPbI3@PCN-221(Fe0.2) in the presence of Fe, indicating
that the photo-induced electrons transfer rapidly from porphyrin
and MAPbI3 QDs to Fe catalytic sites. Furthermore, we also
scrutinized the photoexcited charge separation dynamics by
recording the time-resolved photoluminescence (TRPL) traces
(Figure 3d). The PL traces can be fitted via a multi-exponential
function, and the fitting parameters are given in Table S2. As
shown in Figure 3d, there is a significantly accelerated PL decay
J. L. White, M. F. Baruch, J. E. Pander III, Y. Hu, I. C. Fortmeyer, J. E.
Park, T. Zhang, K. Liao, J. Gu, Y. Yan, T. W. Shaw, E. Abelev, A. B.
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Entry for the Table of Contents
COMMUNICATION
Low-cost CH3NH3PbI3 (MAPbI3)
perovskite quantum dots were
successfully encapsulated in the
pores of cheap Fe-porphyrin derived
MOFs of PCN-221(Fex) to construct
an efficient photocatalytic system,
Li-Yuan Wu, Yan-Fei Mu, Xiao-Xuan
Guo, Wen Zhang, Zhi-Ming Zhang,
Min Zhang,* and Tong-Bu Lu*
Page No. – Page No.
Encapsulating Perovskite Quantum
Dots in Iron-Based Metal-Organic
Frameworks for Efficient
which
displays
significantly
enhanced catalytic efficiency and
stability for visible-light-driven CO2
reduction using water as an electron
source.
Photocatalytic CO2 Reduction
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