Ultrafine RhNi Nanocatalysts Confined in Hollow Mesoporous Carbons for a Highly Efficient Hydrogen Production from Ammonia Borane

Ren Wei, Zhichao Chen, Hao Lv, Xuecheng Zheng, Xin Ge, Lizhi Sun, Kai Song,* Chuncai Kong,*

Article

Ultraﬁne RhNi Nanocatalysts Conﬁned in Hollow Mesoporous

Carbons for a Highly Eﬃcient Hydrogen Production from Ammonia

Borane

∇

Wei Zhang, and Ben Liu *

Cite This: Inorg. Chem. 2021, 60, 6820 −6828

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sı Supporting Information

ABSTRACT: Ammonia borane (AB) has received growing research

interest as one of the most promising hydrogen-storage carrier materials.

However, fast dehydrogenation of AB is still limited by sluggish catalytic

kinetics over current catalysts. Herein, highly uniform and ultraﬁne

bimetallic RhNi alloy nanoclusters encapsulated within nitrogen-function-

alized hollow mesoporous carbons (deﬁned as RhNi@NHMCs) are

developed as highly active, durable, and selective nanocatalysts for fast

hydrolysis of AB under mild conditions. Remarkable activity with a high

turnover frequency (TOF) of 1294 mol mol_R_h⁻min and low activation

−1

−

energy (E ) of 18.6 kJ mol is observed at room temperature, surpassing

the previous Rh-based catalysts. The detailed mechanism studies reveal that

when catalyzed by RhNi@NHMCs, a covalently stable O−H bond by H O

ﬁrst cleaves in electropositive H* and further attacks B−H bond of AB to

stoichiometrically produce 3 equiv of H , whose catalytic kinetics is restricted by the oxidation cleavage of the O−H bond.

Compositional and structural features of RhNi@NHMCs result in synergic electronic, functional, and support add-in advantages,

kinetically accelerating the cleavage of the attacked H O (O−H bond) and remarkably promoting the catalytic hydrolysis of AB

accordingly. This present work represents a new and eﬀective strategy for exploring high-performance supported metal-based alloy

nanoclusters for (electro)catalysis.

INTRODUCTION

recognized as state-of-the-art catalysts for the fast hydrolysis of

AB, but the sluggish kinetics (under mild conditions) still

restrict their large-scale practical applications. Therefore, it is

highly desirable to rationally design and explore other metal-

based catalysts bearing high and selective catalytic activities for

the fast dehydrogenation of AB.

■

One of the most critical issues involving the rapid growth of

industrial production and population in the world is to search

for clean and sustainable energy sources instead of traditional

fossil fuels. The cleanest energy source of the future, hydrogen

has received more attention for its application as highly energy-

−4

Rhodium (Rh), a 4d transition metal, possesses properties

eﬃcient fuel cells.

In comparison to electrochemical water

similar to those of Pt, exhibiting great potential as an

splitting, the catalytic H production from the dehydrogenation

of the chemical hydrogen-storage carrier materials has been

attracting alternative research interests.

24−31

alternative metal catalyst material for H production.

−8

Alloying Rh with more oxophilic 3d metals, for example, Ni

and Co, can not only enlarge the utilization eﬃciency of

precious Rh but also modify its electronic structure and

introduce new functions, both of which would synergistically

Ammonia borane

(

NH −BH , AB), as one of the most promising hydrogen-

storage carries due to the high hydrogen content and good

stability in solid/solution states, has been widely investigated

−12

improve the catalytic performance in various H production

to produce H under mild conditions.

Generally, the

32−40

reactions.

However, ultraﬁne Rh and its alloy nanoclusters

chemical dehydrogenation of AB includes hydrolysis, meth-

anolysis, and dehydrocoupling routes, which strongly corre-

spond to the catalysts and solvents.

1,13

Received: March 9, 2021

Published: April 12, 2021

Among them, the

hydrolysis of AB in H O to produce 3 equiv of H is more

preferable. In the past two decades, vast eﬀorts have been

devoted to developing highly eﬃcient, selective, economical,

and stable catalysts for the fast H production from the

4−23

hydrolysis of AB.

To date, platinum (Pt) and its alloys are

2021 American Chemical Society

820

Inorg. Chem. 2021, 60, 6820−6828

Article

Figure 1. (a) Synthetic procedures of RhNi@NHMCs. (b) SEM, (c, d) TEM, (e) scanning transmission electron microscopy (STEM), (f, g) high-

magniﬁcation TEM and (h) STEM, and (i) high-resolution TEM images of RhNi@NHMCs. (j) STEM energy-dispersive X-ray spectroscopy

(EDS) elemental maps of RhNi@NHMC.

(

<3 nm) would be usually synthesized in the presence of

oxidation cleavage of the covalently stable O−H bond in the

organic stabilizers, which remarkably decreased the Rh active

sites to the reactants and thus deactivated the catalysis. This

limitation might be overcome by ligand-free Rh-based

nanoclusters supported on a solid and high-surface-area matrix

with a precisely desired nanostructure/morphology. Recently,

hollow and mesoporous carbons (HMCs) have become

promising metal catalyst supports to promote catalysis because

of the large surface to uniformly encapsulate the nanoclusters

and the hierarchical structure to kinetically accelerate the

attacked H O (acting as the rate-determining step) and result

in the high activity and selectivity for fast H production from

the hydrolysis of AB. This work represents big progress for the

rational design of the high-performance and supported

nanocatalysts with compositional and structural synergies for

the fast H production from hydrogen-storage materials.

RESULTS AND DISCUSSION

■

The synthetic procedures of RhNi@NHMC are schematically

illustrated in Figure 1a. First, the NHMC support is fabricated

41−44

mass/electron transport in the reaction solution.

Despite

many eﬀorts, supported Rh-based alloy nanocatalysts within

the HMCs have never been reported, which hinders the

fundamental investigations of catalytic performance (activity,

stability, and selectivity) and the corresponding mechanism for

45,46

with the template-free and “soft-nitriding” methods.

Scanning electron microscopy (SEM) shows that the obtained

NHMCs are morphologically spherical with an average

diameter of 320 nm. Transmission electron microscopy

H production from the dehydrogenation of AB.

(

TEM) exhibits they are hollow with a wall thickness of 55

Here, we report a simple self-limiting method for the

encapsulation of highly uniform and ultraﬁne bimetallic RhNi

alloy nanoclusters within nitrogen-functionalized HMCs

nm and a hollow cavity of 210 nm (Figure S1). The high-

magniﬁcation TEM further discloses that the wall framework

of NHMCs is structurally mesoporous with radially opened

pore channels of 7.3 nm. Subsequently, bimetallic RhNi alloys

are grown in situ within the mesoporous channels of the

NHMC support through an under-temperature-reduction-

assisted self-limiting method. Typically, Rh and Ni are

co-impregnated into the N-functionalized channels of the

NHMCs based on the strong coordination interactions

between metal precursors and support and then reduced in

(

deﬁned as RhNi@NHMCs) for the fast hydrolysis of AB

under mild conditions. Beneﬁting from multiple compositional

and structural advantages, RhNi@NHMCs not only display

synergic electronic and functional eﬀects that accelerate

^c^a^t^a^l^y^tⁱ^c^kⁱⁿ^e^tⁱ^c^s^aⁿ^d^o^p^tⁱ^mⁱ^z^e^t^h^e^s^e^l^e^c^tⁱ^vⁱ^t^y^f^o^r^c^o^m^p^l^e^t^e^H2

production but also expose support eﬀects, which facilitates

mass transport and stabilizes RhNi alloys. The catalytic tests

indicate that RhNi@NHMCs possess a remarkably high

activity with a turnover frequency (TOF) of 1294 mol

mol_R_hmin and high selectivity with 3 equiv of produced

H related to AB at 25 °C. Mechanism tests, including the

situ with H at 250 °C to grow ultraﬁne bimetallic RhNi alloy

nanoclusters.

−

−1

RhNi@NHMCs with an Rh/Ni atomic ratio of 1/3 are

thoroughly characterized as an example, since they exhibit the

eﬀects of AB/catalyst amounts and temperatures, kinetic

isotope eﬀect (KIE), and NaOH-promotion experiments,

reveal that RhNi@NHMCs could kinetically accelerate the

best catalytic activity for H production from the hydrolysis of

AB (see below). Similar to the NHMCs, RhNi@NHMCs are

morphologically spherical and structurally hollow and meso-

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Figure 2. (a) SAXS patterns of NHMCs and RhNi@NHMCs. (b) N sorption isotherms, (c) the corresponding pore-size distributions, and (d)

XRD pattern of RhNi@NHMCs. High-resolution X-ray photoelectron spectroscopy (XPS) spectra of (e) Rh 3d and (f) Ni 2p of RhNi@NHMCs.

Figure 3. (a) Time-dependent plots of the produced H and (inset) the corresponding TOF values from the hydrolysis of AB catalyzed by RhNi@

NHMCs, Rh@NHMCs, and commercial Rh/C. (b) Comparisons of the TOF values of RhNi@NHMCs with the previously reported Rh-based

catalysts. (c) Calculated TOF values obtained in diﬀerent Rh/Ni ratios of RhNi@NHMCs. (d) Catalytic cycling stability of RhNi@NHMCs for

the H production from the hydrolysis of AB. The catalytic conditions are as follows: 20 mg of AB, 2.4 mg of catalysts, 7.0 mL of H O, and 25 °C.

porous with very uniform distributions (Figures 1b,d and S2).

This implies that the encapsulation of bimetallic RhNi alloys

does not change the entire morphology and nanostructure of

the NHMC support. In contrast, the high-angle annular dark-

ﬁeld scanning TEM (HAADF-STEM) observation exhibits

numerous bright spots that are homogeneously dispersed

within NHMCs, indicating the formation of bimetallic RhNi

alloys (Figures 1e and S3). High-magniﬁcation TEM images

further conﬁrm the presence of the RhNi alloys (Figure 1f).

Furthermore, TEM and STEM images in higher magniﬁcation

disclose that RhNi alloys are homogeneously encapsulated

within the mesoporous channels of NHMCs, rather than on

the surface of the nanospheres (Figure 1g,h). Bimetallic RhNi

alloys are highly uniform with a diameter of 2.4 ± 0.6 nm.

High-resolution TEM was also characterized, revealing that

bimetallic RhNi alloys have a face-centered cubic (fcc)

crystalline structure (Figure 1i). The d-spacing of RhNi alloys

is 0.21 nm, slightly smaller than that of monometallic Rh. This

conﬁrms that Ni with a smaller atomic size is successfully

alloyed with Rh. Meanwhile, STEM elemental maps display

the coexistence of Rh and Ni, further implying the successful

growth of bimetallic RhNi alloys within the NHMC support.

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Figure 4. Time-dependent plots of the produced H over RhNi@NHMCs, Rh@NHMCs, and Rh/C in (a) diﬀerent AB amounts and (b) catalyst

amounts. Summarizations of relationships (c) between ln TOF and ln [AB] and (d) between ln TOF and ln [Rh]. The catalytic conditions in (a)

and (c) are as follows: diﬀerent amounts of AB, 2.4 mg of catalysts, 7.0 mL of H O, and 25 °C. The catalytic conditions in (b) and (d) are as

follows: 20 mg of AB, diﬀerent amounts of catalysts, 7.0 mL of H O, and 25 °C.

The compositional ratio from STEM energy-dispersive X-ray

spectroscopy (EDS) is measured to be 1:2.7 with a total

loading amount of Rh of 0.96 wt %. This is almost identical to

the result obtained from inductively coupled plasma mass

spectrometry (ICP-MS) (1:3.1).

The mesoporous structure of RhNi@NHMCs is further

characterized to be a nearly two-dimensional (2D) p6mm from

small-angle X-ray scattering (SAXS). After encapsulating RhNi

alloys, the SAXS peaks are retained well, indicating the well-

reserved mesostructures with the d-spacing size of 11.6 nm

2d). Meanwhile, the high-resolution X-ray photoelectron

(XPS) Rh 3d spectra exhibit two pairs of signals assigned to

Rh (major) and Rh (minor) (Figure 2e). Compared to

those in Rh@NHMCs (Figure S4), all of the peaks of XPS Rh

3d in RhNi@NHMCs slightly shift toward the lower binding

energies. This implies the change in surface electronic states of

3−35

Rh after alloying with Ni.

Similarly, three pairs of XPS Ni

2p, which can be assigned to Ni , Ni , and their satellites, are

observed in RhNi@NHMCs, indicating a multielectron

excitation process (Figure 2f).

(

Figure 2a). Meanwhile, the N sorption isotherms of RhNi@

The successful synthesis of ultraﬁne RhNi alloys encapsu-

lated within the NHMCs provided a direct platform to

evaluate their catalytic performance and further understand the

corresponding catalytic mechanism of the room-temperature

hydrolysis of AB. The catalytic performance of RhNi@

NHMCs exhibit a typical type IV loop, conﬁrming the

mesoporous structure of the sample (Figure 2b).

Brunauer−Emmett−Teller (BET) speciﬁc surface area is up to

48,49

The

−1

154 m g , with two distinct pore sizes of 6.8 and 2.9 nm

NHMCs for H production from the hydrolysis of AB was

(Figure 2c). This is a result of the RhNi alloys that occupy

evaluated at 25 °C (298 K). Meanwhile, monometallic Rh@

NHMCs and commercial Rh/C were also investigated for

comparisons (see TEM in Figure S5 ). Obviously, RhNi@

NHMCs exhibited the best activity for the catalytic hydrolysis

parts of mesoporous channels. The mesoporous framework

thickness is thus estimated to be 4.8 nm (11.6−6.8), which is

consistent with the data observed from the TEM and STEM

images.

Wide-angle X-ray diﬀraction (XRD) was also studied for

revealing the crystalline structure of the bimetallic RhNi alloys

in RhNi@NHMCs. Four diﬀraction peaks appear in the region

of 35−90°, suggesting that RhNi nanoclusters are composi-

tionally well-alloyed with an fcc crystalline structure (Figure

of AB with a complete H production time of 2.0 min (Figure

a). This corresponded to a superior turnover frequency

−

−1

(

^T^O^F⁾^v^a^l^u^e^o^f¹²⁹⁴^m^o^l^H2 ^m^o^lRh min . By comparison, the

hydrolysis times catalyzed by Rh@NHMCs and Rh/C

prolonged to 2.8 and 32.0 min with the TOF values of 708

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Figure 5. (a) Time-dependent plots of the produced H over RhNi@NHMCs, Rh@NHMCs, and Rh/C under diﬀerent test temperatures. (b)

Relationships between ln TOF and 1000/T and (c) calculated E values of RhNi@NHMCs, Rh@NHMCs, and Rh/C. The catalytic conditions are

as follows: 20 mg of AB, 2.4 mg of catalysts, 7.0 mL of H O, and diﬀerent test temperatures.

and 75 mol_H₂mol_R_h⁻min , respectively. Besides, all three

−1

Rh/C. Impressively, the plots are completely overlapped in the

initial stages for all three samples (<30 mL of H produced).

catalysts produced ∼42 mL of H with an exact H /AB ratio of

3.0, indicating that H atoms bonded with B in AB were

totally hydrolyzed with 3 moles of H O. This also conﬁrmed

that all of the catalysts had nearly 100% H selectivity for the

catalytic hydrolysis of AB. When further compared with Rh-

based and other catalysts reported before (Tables S1 and

RhNi@NHMCs also represented the high active

nanocatalyst for H production from the room-temperature

Meanwhile, their logarithmic plots of H (ln TOF) and AB

∼

concentration (ln [AB]) are nearly horizontal, indicating zero-

order kinetics with respect to AB concentrations (Figure

20,37

c).

This rules out the cleavage of B−N and B−H bonds

as the rate-determining step, when the above samples are used

^a^s^c^a^t^a^l^y^s^t^s^.^Iⁿ^c^oⁿ^t^r^a^s^t^,^t^h^e^r^a^t^e^s^o^f^H2 production are

obviously accelerated with the increasing catalyst (Rh)

concentrations (Figure 4b). Their slopes of ln TOF and ln

8,29,50−53

S2 ),

hydrolysis of AB (Figure 3b).

[

Rh] are also calculated to be 1.09 for RhNi@NHMCs, 0.73

The compositional eﬀect of binary RhNi alloys in RhNi@

NHMCs on the catalytic activity of the hydrolysis of AB is also

investigated (see Figure S6 for TEM images). As shown in

Figure 3c, with increasing Rh amounts, the catalytic activities

dramatically increase and reach the top with an optimum Rh/

Ni of 1/3. Then, the catalytic activities slightly decrease with a

further increase in Rh amounts. The volcano-like activities

agree well with the previous reports in bimetallic nanocatalysts,

conﬁrming the importance of the compositional synergies of

for Rh@NHMCs, and 0.83 for Rh/C (Figure 4d). This

suggests that the hydrolysis of AB is a ﬁrst-order reaction in the

catalyst (Rh) concentrations. Among them, RhNi@NHMCs

hold a slightly higher slope (quicker catalysis), conﬁrming the

favorable hydrolysis for H production.

The temperature eﬀect of the above Rh-based catalysts in

the hydrolysis of AB is further investigated. The hydrolysis of

AB is dramatically accelerated with the increase in the test

temperature from 293 to 313 K (Figure 5a). The relations

between ln TOF and 1/1000 are also presented, which match

well with the Arrhenius plots (Figure 5b). The activation

the catalysis. The catalytic stability of optimized RhNi@

NHMCs is further evaluated by consecutively injecting fresh

AB into the previous solution. The rates of H production only

slightly decrease during the cycling tests with the complete H₂

production time of 3.5 min at ﬁve cycles (Figure 3d) because

of the functional NHMC support that anchors and conﬁnes

the RhNi alloys. In comparison, commercial Rh/C is quickly

deactivated during cycling tests (Figure S7). These results

coincide with the high eﬃciency of RhNi@NHMCs for the H₂

production from the hydrolysis of AB under ambient

conditions (see Figure S8 for the TEM images after the

stability tests).

energy (E

) was further calculated based on the Arrhenius

value

values of Rh@

equation. Obviously, RhNi@NHMCs hold the lowest E

of 18.6 kJ mol . By sharp comparison, the E

NHMCs and Rh/C are 38.6 and 61.5 kJ mol , respectively

−

(Figure 5c). The lowest E conﬁrmed that, in comparison to

Rh@NHMCs and Rh/C, RhNi@NHMCs have a thermody-

namically lowest energy barrier and thus favorably accelerate

20,54

the H production from the hydrolysis of AB.

There are several catalytic mechanisms of the hydrolysis of

The catalytic kinetics of RhNi@NHMCs for the hydrolysis

of AB was thoroughly evaluated and further compared with

Rh@NHMCs and commercial Rh/C. Figure 4a shows the

AB over metal-based catalysts. Xu proposed that H O was ﬁrst

activated and further attacked and cleaved the B−N bond.

Then, the hydrolysis of the cleaved NH produced H

time-dependent plots of the produced H under diﬀerent AB

accordingly. Jagirdar and Ma thought that H in B−H of

amounts catalyzed by RhNi@NHMCs, Rh@NHMCs, and

NH −BH was cleaved in the attack of H O and adsorbed on

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Figure 6. (a) Time-dependent plots of the produced H over RhNi@NHMCs in H O and D O. (b) Time-dependent plots of the produced H

over RhNi@NHMCs in diﬀerent NaOH concentrations. (c) Proposed catalytic mechanism for the room-temperature hydrolysis of AB catalyzed by

RhNi@NHMCs. The catalytic conditions in (a) are as follows: 20 mg of AB, 2.4 mg of catalysts, 7.0 mL of H O (or D O), and 25 °C. The catalytic

conditions in (b) are as follows: 20 mg of AB, 2.4 mg of catalysts, 7.0 mL of H O, diﬀerent concentrations of NaOH, and 25 °C.

metal catalysts (via M−H bond). After that, another H O

catalytic hydrolysis of AB under ambient conditions (Figure

6c). On one hand, alloying more oxophilic Ni with Rh would

introduce new surface functions that favor the coordination of

4,56

further attacked the M−H intermediate to produce H .

−

Besides, Fu proposed that NH −BH (OH ) intermediate

formed by the attacked H O was the key for H production.

O on the Ni surface (via H

facilitate the oxidation cleavage of the O−H bond in the

attacked H O (functional eﬀect). On the other hand, alloying

Ni could modify the surface electronic structure of Rh and

thermodynamically lower the E on the Rh surface (electronic

eﬀect). This directly accelerates the oxidation cleavage of the

N−BH -H···H−OH) and thus

Very recently, Chen, Duan, and Austruc have highlighted that

the oxidation cleavage of the O−H bond in the attacked H O

was the rate-determining step for the H production from the

hydrolysis of AB, especially when catalyzed by noble-metal

6,18,58

catalysts.

O−H bond in the attacked H O. Meanwhile, spatially

To unveil the catalytic mechanism for the room-temperature

hydrolysis of AB over RhNi@NHMCs, more kinetic experi-

ments were carefully designed and carried out. First, isotopic

experiments with D O instead of H O as the solvent and

separated catalytic sites of Rh and Ni in an optimum

compositional ratio (1/3) synergistically accelerate the

cleavage of H O for H production. Furthermore, hierarchical

hollow and mesoporous nanospheres are able to kinetically

facilitate electron/mass transport in the reaction solution,

while N-functionalized surface on NHMCs partially optimizes

reactant were performed for the catalytic hydrolysis of

8,59,60

AB.

As shown in Figure 6a, the hydrolysis rates were

remarkably decelerated in the presence of D O, compared to

the coordination of H O on the supports. They also cause

H O. The kinetic isotope eﬀect (KIE) was calculated to be

improved coordination of H O on the catalyst surface,

.96, clearly conﬁrming that the rate-determining step was the

therefore kinetically promoting the H production from the

oxidation cleavage of the covalently stable O−H bond (rather

hydrolysis of AB.

than the cleavage of the B−N and B−H bonds in AB) when

−

catalyzed by RhNi@NHMCs. Meanwhile, the role of OH was

further investigated by conducting the hydrolysis reactions in

CONCLUSIONS

■

20,61

diﬀerent NaOH concentrations (Figure 6b).

Interestingly,

We report an eﬀective self-limiting method to grow in situ

supported ultraﬁne bimetallic RhNi nanocatalysts on N-

functionalized HMCs and demonstrate their high eﬃciency

the hydrolysis activities were remarkably enhanced with the

increasing NaOH concentrations and reached the top value at

.5 M NaOH with a very high TOF value of 2589 mol

for H production from the room-temperature hydrolysis of

mol_R_hmin⁻¹(Figure S9 ). This TOF value in 0.5 M NaOH

−1

AB. The obtained RhNi@NHMCs hold a very high TOF value

−

−1

was 2.0 times higher than that without NaOH. This indicates

of 1294 mol mol_R_hmin and a low E value of 18.6 kJ

−

that OH can be favorably coordinated on the catalyst and

mol , representing the top level ever developed for alternative

noble-metal catalysts. Detailed kinetics investigations, includ-

result in a more electron-rich surface, which would beneﬁt the

rate-limiting oxidation coordination of H O. However, the

ing D O replacement and NaOH-promotion experiments,

hydrolysis activities became slightly worse in the higher NaOH

reveal that, when catalyzed by RhNi@NHMCs, the rate-

determining step is the oxidation cleavage of the covalently

stable O−H bond, rather than the cleavage of the B−N and

B−H bonds. Compositional and structural advantages of

RhNi@NHMCs result in multiple functional, electronic, and

support synergies for the hydrolysis of AB. We demonstrate

that functional and electronic eﬀects of bimetallic RhNi alloys

−

concentrations, since excessive OH could cover the catalytic

sites for the oxidation cleavage of the O−H bond.

According to the above discussions, we ascribe the higher

activity of RhNi@NHMCs to their multiple compositional and

structural synergies that kinetically accelerate the oxidation

cleavage of the covalently stable O−H bond in the attacked

H O (the rate-determining step) and accordingly promote the

facilitate the coordination of H O and accelerate the oxidation

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Inorg. Chem. 2021, 60, 6820−6828

Inorganic Chemistry

The Supporting Information is available free of charge at

Article

cleavage of the O−H bond in the attacked H O, while a

Notes

hierarchical HMC support optimizes the electron/mass

transport during the hydrolysis of AB. The utilization of the

supported Rh-based alloys to fabricate highly active catalytic

sites might be easily extended to other metal alloy catalyst

systems with deﬁned functional and electronic synergies for

various targeted catalytic reactions.

The authors declare no competing ﬁnancial interest.

ACKNOWLEDGMENTS

■

The authors thank the Center of Engineering Experimental

Teaching, School of Chemical Engineering, Sichuan University

for the TEM and STEM support. This work was ﬁnancially

supported by the National Natural Science Foundation of

China (31870486), the Natural Science Foundation of Jiangsu

Province (BK20180723), the National Natural Science

Foundation of Shaanxi Province (2020JZ-03, 2021JLM-27),

the China Postdoctoral Science Foundation (2019M663690),

and the research fund from Priority Academic Program

Development of Jiangsu Higher Education Institutions.

ASSOCIATED CONTENT

sı Supporting Information

https://pubs.acs.org/doi/10.1021/acs.inorgchem.1c00721.

■

Details of the synthesis, characterizations, and catalytic

measurements and more SEM and TEM images as well

as the evaluation of catalytic performances (PDF)

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■

AUTHOR INFORMATION

Corresponding Authors

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■

Non-Interstitial Hydrides for the Storage and Production of

Kai Song − School of Life Science, Changchun Normal

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Ben Liu − Jiangsu Key Laboratory of New Power Batteries,

Jiangsu Collaborative Innovation Center of Biomedical

Functional Materials, School of Chemistry and Materials

Science, Nanjing Normal University, Nanjing 210023,

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