Efficient visible light initiated hydrothiolations of alkenes/alkynes over Ir2S3/ZnIn2S4: Role of Ir2S3

Article abstract of DOI:10.1016/S1872-2067(20)63660-9

The hydrothiolations of alkynes/alkenes with thiols is an atom-economic and thus attractive method for the constructions of C-S bonds. Here Ir₂S₃/ZnIn₂S₄ nanocomposites with varied Ir₂S₃ loadings were obtained by one-pot solvothermal method from ZnCl₂, InCl₃ and thioacetamide with IrCl₃. The loading of Ir₂S₃ on the surface of ZnIn₂S₄ promoted the hydrothiolations of alkenes and alkynes, with an optimum performance observed over 0.5 molpercent Ir₂S₃/ZnIn₂S₄ nanocomposite. Based on the studies on the performance of several other cocatalysts (MoS₂, NiS and Pd) loaded ZnIn₂S₄ and the EIS analyses, it was proposed that the superior performance over Ir₂S₃/ZnIn₂S₄ nanocomposite can be ascribed to an improved efficiency on the photogeneration of the thiyl radicals by loading Ir₂S₃ as well as its inactivity for photocatalytic hydrogen evolution, a side reaction in the light initiated hydrothiolation reaction over ZnIn₂S₄. This study not only demonstrates an efficient and green strategy to synthesize thiolated products under visible light based on semiconductor photocatalysis, but also provides some guidances for the design and development of photocatalytic systems for light induced organic syntheses.

Full text of DOI:10.1016/S1872-2067(20)63660-9

Chinese Journal of Catalysis 42 (2021) 409–416
a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / c h n j c
Article
Efficient visible light initiated hydrothiolations of alkenes/alkynes
over Ir2S3/ZnIn2S4: Role of Ir2S3
Xinglin Wang, Yuanyuan Li, Zhaohui Li 
Research Institute of Photocatalysis, State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou
350116, Fujian, China
A R T I C L E I N F O
A B S T R A C T
Article history:
The hydrothiolations of alkynes/alkenes with thiols is an atom‐economic and thus attractive meth‐
od for the constructions of C‒S bonds. Here Ir2S3/ZnIn2S4 nanocomposites with varied Ir2S3 loadings
were obtained by one‐pot solvothermal method from ZnCl2, InCl3 and thioacetamide with IrCl3. The
loading of Ir2S3 on the surface of ZnIn2S4 promoted the hydrothiolations of alkenes and alkynes, with
an optimum performance observed over 0.5 mol% Ir2S3/ZnIn2S4 nanocomposite. Based on the
studies on the performance of several other cocatalysts (MoS2, NiS and Pd) loaded ZnIn2S4 and the
EIS analyses, it was proposed that the superior performance over Ir2S3/ZnIn2S4 nanocomposite can
be ascribed to an improved efficiency on the photogeneration of the thiyl radicals by loading Ir2S3 as
well as its inactivity for photocatalytic hydrogen evolution, a side reaction in the light initiated hy‐
drothiolation reaction over ZnIn2S4. This study not only demonstrates an efficient and green strate‐
gy to synthesize thiolated products under visible light based on semiconductor photocatalysis, but
also provides some guidances for the design and development of photocatalytic systems for light
induced organic syntheses.
Received 19 May 2020
Accepted 25 June 2020
Published 5 March 2021
Keywords:
Photocatalysis
Ir2S3/ZnIn2S4
Alkenes
Alkynes
Hydrothiolation
© 2021, Dalian Institute of Chemical Physics, Chinese Academy of Sciences.
Published by Elsevier B.V. All rights reserved.
1. Introduction
develop green and sustainable processes for chemical reaction,
the use of solar energy to drive chemical transformations has
The construction of C‒S bonds is important in synthetic or‐
ganic chemistry since a large amount of natural products and
pharmaceuticals contain C‒S bonds in their structures and
sulfur‐containing products are receiving increasing attention in
polymer and material chemistry [1]. Among the various strate‐
gies developed, the hydrothiolations of unsaturated hydrocar‐
bons with thiols is an atom‐economic and thus attractive strat‐
egy for the construction of C‒S bonds [2,3]. The met‐
al‐catalyzed hydrothiolations of unsaturated hydrocarbons
with thiols can proceed with good to excellent regio‐ and ste‐
reoselectivity to sulfur containing molecules [4–6]. Recently, to
attracted extensive research interest [7–10]. Semiconductors,
in particular narrow‐band‐gap metal sulfides [11], have shown
great potential in visible light induced organics transformations
under mild conditions [12,13].Specifically, the development of
photoredox systems to realize the hydrothiolation reactions
under visible light has also been demonstrated [14–16]. Ho‐
mogeneous photocatalysts like Ru (II) complexes [17,18], dyes
(Eosin Y) [19] as well as heterogeneous semiconducting TiO2
[20] and ZnIn2S4 [21] have all been reported to realize the hy‐
drothiolation reactions under visible light. In these photoredox
systems, thiyls, the synthetically useful radicals generated in
* Corresponding author. Tel/Fax: +86‐591‐22865855; E‐mail: haohuili1969@yahoo.com
This work was supported by the National Natural Science Foundation of China (21872031, U1705251) and the Award Program for Minjiang Scholar
Professorship.
DOI: 10.1016/S1872‐2067(20)63660‐9 | http://www.sciencedirect.com/science/journal/18722067 | Chin. J. Catal., Vol. 42, No. 3, March 2021

410
Xinglin Wang et al. / Chinese Journal of Catalysis 42 (2021) 409–416
the photoredox cycle, attack the unsaturated hydrocarbons
(alkenes or alkynes) to generate the hydrothiolated products
via a radical addition cycle. As compared with the direct
addition of thiols to unsaturated hydrocarbons, in which the
thiyls are generated by thermal/UV activation of a radical
initiator or by direct irradiation with UV light [22,23], which
usually requires harsh reaction conditions and leads to low
selectivity with the possible formation of by‐products as well as
limited application to only simple systems [24–26], the
hydrothiolations over these photoredox systems are more
selective since the reactions can be carried out under mild
conditions and no special UV equipments was required. In
addtion, these reactions protocols can be applied to expaned
substrate scopes.
All the reagents were commercially available and used
without further purifications. For the synthesis of Ir2S3/ZnIn2S4,
different amounts of IrCl3 was dispersed in a mixed solution
containing 30 mL of N,N‐dimethylformamide (DMF) and 30 mL
of ethylene glycol (EG). ZnCl2 (0.136 g, 1mmol), InCl3·4H2O
(0.586 g, 2mmol) and thioacetamide (TAA) (0.3 g, 4 mmol)
were added under vigorous stirring. The resultant suspension
was transferred to a 100 mL Teflon liner, sealed and heated at
180 °C for 18 h. After the reaction, the autoclave was cooled,
and the product was collected and washed with deionized wa‐
ter and ethanol for several times and dried overnight at 60 °C.
The Ir2S3/ZnIn2S4 nanocomposites with different amount of
Ir2S3 were denoted as x mol% Ir2S3/ZnIn2S4. Bare ZnIn2S4 was
synthesized similarly in a reaction without the introduction of
IrCl3.
Among the already reported photoredox systems for light
initiated hydrothiolation reactions, ZnIn2S4,
a promising
semiconductor which has been widely used in a variety of
photocatalytic applications [27–29], is in particular appealing
since the hydrothiolations over ZnIn2S4 can be carried out in a
green solvent (methanol), with only stoichiometric thiols
required and applicable to a broad substrate scope, which
makes it a green, sustainable and cost‐effectively strategy for
the synthesis of thiolated products [21]. In addition, ZnIn2S4 is
cheap and non‐toxic [30,31]. However, the light initiated
hydrothiolation reactions for some bulky substrates over bare
ZnIn2S4 are still not so high. Considering that the light initiated
hydrothiolation reactions over ZnIn2S4 is a coupling of the
photoredox generation of the thiyl radicals and the successive
radical addition to produce the desired hydrothiolated
products [21], it is therefore proposed that an improved
efficiency in the photogeneration of the thiyl radicals would be
beneficial to the whole hydrothiolation reactions [32,33].
Cocatalysts have been widely used in photocatalysis to
promote a variety of photocatalytic reactions since they can
improve the separation of the photogenerated charge carriers
and promote their transportation [34–43].
2.2. Catalytic reactions
The visible light induced hydrothiolation reactions were
carried out in a sealed reaction tube irradiated with an LED
lamp (Beijing Perfect Light, PCX50B). The catalyst (10 mg),
thiol (0.1 mmol) and alkynes/styrene (0.12 mmol) were sus‐
pended in a Schlenk tube containing methanol (4 ml). Before
the reaction, the suspension was degassed and saturated with
N2 to remove any dissolved O2. The reaction was performed
under irradiation for 15 h with an LED lamp (65 mW cm‒2)
irradiated from bottom, with the reaction suspension continu‐
ously stirring during the whole reaction. A photograph of the
experimental set‐up has been provided in Supporting Fig. S5.
After reaction, the mixture was filtered through a porous
membrane (20 μm in diameter) and the filtrate was analyzed
by GC‐MS and GC‐FID (Shimadzu GC‐2014) equipped with an
HP‐5 capillary column.
3. Results and discussion
In this manuscript, to improve the performance of ZnIn2S4
for light initiated hydrothiolation, Ir2S3 was loaded on the
surface of ZnIn2S4 via a one‐step solvothermal method and the
as‐obtained Ir2S3/ZnIn2S4 nanocomposites was used in the
visible light initiated thiol‐ene and thiol‐yne coupling reactions.
It was found that loading of Ir2S3 on the surface of ZnIn2S4 did
promote the hydrothiolations of alkenes and alkynes, with an
optimum performance observed over 0.5 mol% Ir2S3/ZnIn2S4
nanocomposite. The superior performance over Ir2S3/ZnIn2S4
nanocomposites can be ascribed to an improved efficiency on
the photogeneration of the thiyl radicals by loading Ir2S3 as well
as its inactivity for photocatalytic hydrogen evolution, a side
reaction in the light initiated hydrothiolations over ZnIn2S4.
This work provides an efficient and green strategy to
synthesize thiolated products based on semiconductor
photocatalysis.
Similar to that for the preparation of bare ZnIn2S4 [27,44],
Ir2S3/ZnIn2S4 nanocomposites with different loading amount of
Ir2S3 were obtained by one‐pot solvothermal method from
ZnCl2, InCl3 and TAA in a mixed solvent of DMF and EG, with the
presence of different amounts of IrCl3. The XRD patterns of the
products show 2θ peaks at values of 14.3°, 21.2°, 27.7°, 30.4°,
39.3°, 47.5°, 52.1°, 55.8° and 76.4°, which can be assigned to
(004), (006), (102), (104), (108), (110), (116), (022) and (123)
crystallographic planes of hexagonal ZnIn2S4 phase (JCPDS
65‐2023) [31], indicating that the introduction of Ir species
does not influence the formation of hexagonal ZnIn2S4 (Fig. 1).
No diffraction peak corresponding to either metallic Ir or
Ir‐containing compound was observed in the XRD patterns,
probably due to the low amount of Ir introduced in the prod‐
ucts. However, the presence of Ir in the as‐obtained products
was evidenced from the XPS. As shown in Fig. 2(a), the XPS
spectrum of the product with 0.5 mol% Ir loaded in Ir 4f region
shows peaks at binding energy of 61.68 eV for Ir 4f7/2 and 64.91
eV for Ir 4f5/2 respectively, suggesting that Ir exists as Ir3+ [45].
The XPS spectrum in S 2p region can be deconvoluted into two
sets of peaks, indicating that S exists in two different chemical
2. Experimental
2.1. Preparation

Xinglin Wang et al. / Chinese Journal of Catalysis 42 (2021) 409–416
411
and 452.34 eV, in the as‐obtained Ir2S3/ZnIn2S4, slightly shift to
higher binding energies as compared with those in bare
ZnIn2S4, indicating the existence of the interaction between the
surface of deposited Ir2S3 and ZnIn2S4 (Figs. 2(c), (d)). The SEM
image of 0.5 mol% Ir2S3/ZnIn2S4 shows that it consists of flow‐
er‐like microspheres with dimension of ca. 2–3 μm (Fig. 3(a)).
The TEM image shows that each microsphere is assembled by
very thin nanosheets (Fig. 3(b)). As compared with bare
ZnIn2S4, it is obvious that the deposition of Ir2S3 on the surface
of ZnIn2S4 does not change its morphology. The HRTEM image
shows that Ir2S3 nanoparticles of ca. 6 nm, were deposited on
the nanosheet of ZnIn2S4. Clear lattice fringes of 0.291 nm, cor‐
responding to (102) crystallographic plane of Ir2S3, can be ob‐
served. In addition, lattice fringes of 0.322 nm, which belongs to
(102) crystallographic plane of hexagonal ZnIn2S4, are also
observed, which again confirms the deposition of Ir2S3 in hex‐
agonal ZnIn2S4. The EDX mapping of 0.5ꢀmol% Ir2S3/ZnIn2S4
nanocomposite also confirms the presence of Ir and its even
distribution on the surface of ZnIn2S4 (Fig. S1).
The UV‐vis DRS of Ir2S3/ZnIn2S4 nanocomposites with
different amount of Ir2S3 were displayed in Fig. 4. All the
Ir2S3/ZnIn2S4 nanocomposites show light absorption in the
visible light region, with an absorption edge extending to 550
nm, in accordance with their yellow color. As compared with
bare ZnIn2S4, the deposition of Ir2S3 on the surface of ZnIn2S4
does not influence its light absorption.
To study the performance of Ir2S3/ZnIn2S4 for visible light
initiated hydrothiolation reactions, the reaction between
phenylacetylene (1a) and benzyl mercaptan (2a) was first
selected as the model reaction. The reaction was initially
(d) 2 mmol% Ir2S3/ZnIn2S4
(c) 1 mmol% Ir2S3/ZnIn2S4
(b) 0.5 mmol% Ir2S3/ZnIn2S4
(a) ZnIn2S4
(d)
(c)
(b)
(a)
20
40
2/(o )
60
80
Fig. 1. XRD patterns of different samples. (a) ZnIn2S4; (b) 0.5 mol%
Ir2S3/ZnIn2S4; (c) 1 mol% Ir2S3/ZnIn2S4; (d) 2 mol% Ir2S3/ZnIn2S4.
environments (Fig. 2(b)). Considering that Ir exists as Ir3+ and
by comparison with the XPS of bare ZnIn2S4, the peaks with
binding energy at 161.38 and 162.62 eV can be assigned to S
2p3/2 and S 2p1/2 in ZnIn2S4, while the other two peaks with
binding energy at 161.77 and 162.89 eV can be attributed to S
2p3/2 and S 2p1/2 in Ir2S3, respectively. The formation of Ir2S3 on
the surface of hexagonal ZnIn2S4 is not unexpected since pre‐
vious studies also demonstrated that the surface deposited PtS
was obtained via a photoreduction of PtCl62‒ over ZnIn2S4 [46].
Both Zn 2p, with binding energies located at 1021.52 and
1044.55 eV for Zn 2p3/2 and 2p1/2, and In 3d, located at 444.83
(b)
(a)
161.38
61.68
64.91
162.62
161.77
162.89
64
68
72
160
164
168
Binding energy (eV)
Binding energy (eV)
(d)
(c)
452.34
448.83
1021.52
1044.55
1020
1030
1040
1050
444
448
452
456
Binding energy (eV)
Binding energy (eV)
Fig. 2. XPS spectra of 0.5ꢀmol% Ir2S3/ZnIn2S4 nanocomposite. (a) Ir 4f ; (b) S 2p; (c) Zn 2p; (d) In 3d.

412
Xinglin Wang et al. / Chinese Journal of Catalysis 42 (2021) 409–416
Table 1
Light initiated hydrothiolation between benzyl mercaptane and phe‐
nylacetylene over Ir2S3/ZnIn2S4 under different conditions.
Fig. 3. SEM (a), TEM (b) and HRTEM (c) image 0.5ꢀmol% Ir2S3/ZnIn2S4
nanocomposite.
Entry
1
2
3
4
5c
6d
7f
Catalyst
Conv a (%) Yield of 3ab (%)
1 mol% Ir2S3/ZnIn2S4
2 mol% Ir2S3/ZnIn2S4
0.5 mol% Ir2S3/ZnIn2S4
ZnIn2S4
99
91
97
94
0
94
85
95
90
0
proceeded in methanol over 1.0 mol% Ir2S3/ZnIn2S4 since
previous study revealed that methanol was the best solvent for
the light initiated hydrothiolation reaction over ZnIn2S4. Similar
to bare ZnIn2S4, 1.0 mol% Ir2S3/ZnIn2S4 is also active for the
reaction between phenylacetylene (1a) and benzyl mercaptan
(2a) to produce benzyl styryl sulfide (3a). 99 % of benzyl
mercaptane was converted after irradiated for 15 h, with a
yield of 94% to benzyl styryl sulfide (3a), a performance
superior to that over bare ZnIn2S4 (Table 1, entry 1). The
amount of Ir2S3 loaded influences the performance of
Ir2S3/ZnIn2S4 (Table 1, entries 2 and 3). Among the three
Ir2S3/ZnIn2S4 nanocomposites (0.5, 1.0 and 2.0 mol%)
investigated, Ir2S3/ZnIn2S4 nanocomposite with 0.5 mol% Ir2S3
loaded exhibited an optimum performance, with 97% of
phenylacetylene converted and a yield of 95% to the desired
product benzyl styryl sulfide (3a). Therefore, the following
investigations were carried out over 0.5 mol% Ir2S3/ZnIn2S4
nanocomposite.
—
0.5 mol% Ir2S3/ZnIn2S4
0.5 mol% Ir2S3/ZnIn2S4
trace
5
trace
5
Reaction conditions: 1a (0.12 mmol), 2a (0.1 mmol), cat. (10 mg),
CH3OH (4 ml), visible light irradiation for 15 h. a Calculated based on 2a.
b Based on GC analyses. c No catalyst. d Without light. f TEMPO was added
in the reaction.
70% respectively to desirable hydrothiolated products 3f, 3h
and 3j over Ir2S3/ZnIn2S4, as compared with yields of 61%,
56% and 51% respectively over bare ZnIn2S4. In addition to the
Table 2
Investigations of the substrate scope of visible‐light‐initiated hydrothi‐
olations of alkynes and alkenes over 0.5 mol% Ir2S3/ZnIn2S4.
Similar to the reactions over bare ZnIn2S4, the visible light
initiated thiol‐yne reactions over 0.5 mol% Ir2S3/ZnIn2S4
nanocomposite can also be applied to a wide range of substrate
scopes (Table 2). The hydrothiolation reactions between
phenylacetylenes with different substituents and different
thiols, including both aliphatic and aromatic thiols as well as
thiophenols, led to desirable thiolated products with yields
ranged in 70%–96%. As compared with bare ZnIn2S4, 0.5 mol%
Ir2S3/ZnIn2S4 nanocomposite showed superior performance for
all the thiol‐yne reactions (Table 2, 3b–3l). In particular, obvi‐
ous improvement in the activity was observed over those bulky
substrates. For example, the reactions of 1a and
4‐tert‐butylbenzylthiol, 1a and dodecyl mercaptan as well as
1a and 2‐naphthyl mercaptans gave yields of 89%, 76% and
3b, 95 (92)
3c, 92 (81)
3d, 93 (93)
3e, 90 (82)
3h, 76 (56)
3f, 89 (61)
3i, 81 (70)
3g, 96 (95)
3j, 70 (51)
2mol% Ir2S3/ZnIn2S4
1mol% Ir2S3/ZnIn2S4
0.5mol% Ir2S3/ZnIn2S4
ZnIn2S4
3k, 70 (58)
4b, 62 (49)
4f, 69 (50)
3l, 76 (60)
4c, 74 (55)
4g, 77 (61)
4a, 80(58)
4d, 82 (63)
4h, 42 (30)
Reaction conditions: alkynes or styrene (0.12 mmol), thiols (0.1 mmol),
Ir2S3/ZnIn2S4 (10 mg), CH3OH (4 mL), visible light irradiation for 15 h.
Conversion was calculated based on thiols; The amount of the products
was calculated based on GC and GC‐MS; The content in parentheses was
the yields of the reaction over bare ZnIn2S4 according to Ref. [21].
300
400
500
600
700
800
Wavelength/nm
Fig. 4. UV‐visible diffuse reflectance spectra of ZnIn2S4, 0.5 mol%
Ir2S3/ZnIn2S4, 1 mol% Ir2S3/ZnIn2S4, 2 mol% Ir2S3/ZnIn2S4.

Xinglin Wang et al. / Chinese Journal of Catalysis 42 (2021) 409–416
413
100
80
60
40
20
0
100
(a)
(b)
80
60
40
20
0
(1)
(2)
20
40
60
80
1
2
3
2/( o )
Cycling times
Fig. 5. (a) Cycling of the hydrothiolation reaction between phenylacetylene and benzyl mercaptane over Ir2S3/ZnIn2S4 under visible light irradiation;
(b) XRD patterns of (a) used Ir2S3/ZnIn2S4 after three cycling reactions (1) and fresh Ir2S3/ZnIn2S4 (2).
thiol‐yne reactions, the introduction of Ir2S3 also promoted all
the investigated thiol‐ene reactions. 0.5 mol% Ir2S3/ZnIn2S4
showed superior performance for all the light initiated hyrothi‐
olation reactions between styrene and different thiols, with
better yields of 42%–82% to the desirable products, as com‐
pared with yields of 49%–63% over bare ZnIn2S4 (Table 2,
4a–4h). Similar to that observed over the thiol‐yne reactions,
the degree of improvement on the performance of thiol‐ene
reactions is more obvious in those bulky thiols. For example,
the reactions between styrene and 4‐tert‐butylbenzylthiol
ordodecyl mercaptan gave yields of 74% and 69% to the de‐
sired products (4c and 4f) over Ir2S3/ZnIn2S4, as compared
with 55% and 50% respectively over bare ZnIn2S4. It is obvious
that the loading of Ir2S3 as a cocatalyst can promote the light
initiated hydrothiolation reactions between unsaturated hy‐
drocarbons with different thiols over ZnIn2S4. Ir2S3/ZnIn2S4
also shows high stability during the reactions. No obvious loss
of the activity was observed after three cycling tests (Fig. 5(A))
and the catalyst after three runs showed almost unchanged
XRD patterns (Fig. 5(B)).
carriers. This assumption was confirmed by the EIS results. As
shown in Figs. 6(a) and 6(e), EIS Nyquist plot of Ir2S3/ZnIn2S4
nanocomposite shows a smaller radius as compared with that
of bare ZnIn2S4, indicating that the loading of Ir2S3 enhances the
charge separation and transportation in ZnIn2S4.
Since cocatalysts have been widely used to promote the
separation and transportation of the photogenerated charge
carriers in photocatalysis, several other generally used cocata‐
lysts, including MoS2, NiS and Pd NPs, were also deposited on
ZnIn2S4 and was denoted as MoS2/ZnIn2S4, NiS/ZnIn2S4 and
Pd/ZnIn2S4, respectively. The preparations of MoS2/ZnIn2S4,
NiS/ZnIn2S4 and Pd/ZnIn2S4 followed the procedures reported
previously [27,31,37], with their XRD patterns showed in the
supporting information Figs. S2–S4. The performance of the
as‐obtained ZnIn2S4 nanocomposites for light initiated hy‐
drothiolation reaction was investigated. As shown in Figs. 6(b),
6(c) and 6(d), the loading of all three cocatalysts on ZnIn2S4
also improves the separation of photogenerated charge carriers
3000
Light initiated hydrothiolation reactions over ZnIn2S4 has
been proposed to be a coupling of a photoredox cycle and a
radical addition cycle, in which the first step involves the attack
on the thiols by the photogenerated holes on ZnIn2S4 to gener‐
ate the thiyl radicals. To investigate whether radicals are also
involved in the hydrothiolation reactions over Ir2S3/ZnIn2S4,
controlled experiment was carried out by addition of TEMPO, a
radical trapping agent, into the reaction system. It was found
that the introduction of TEMPO led to an almost complete
quench of the hydrothiolation reaction, with the yield to the
benzyl styryl sulfide significantly decreased to 5% under oth‐
erwise similar conditions (Table 1), indicating that radicals are
also involved in the light initiated hydrothiolation reactions
over Ir2S3/ZnIn2S4 nanocomposites. It is therefore proposed
that the promoting effect on the light initiated hydrothiolation
reaction by loading Ir2S3 on ZnIn2S4 should be ascribed to an
improved efficiency in the photogeneration of the thiyl radicals,
due to the introduction of Ir2S3 as a cocatalyst to improve the
separation and transportation of the photogenerated charge
1500
Ir2S3/ZnIn2S4-a
MoS2/ZnIn2S4-b
NiS/ZnIn2S4-c
Pd/ZnIn2S4-d
ZnIn2S4-e
0
0
2000
4000
Z'' (ohm)
Fig. 6. Nyquist plots of experimental impedance data for bare ZnIn2S4,
Ir2S3/ZnIn2S4, MoS2/ZnIn2S4, NiS/ZnIn2S4 and Pd/ZnIn2S4 in the fre‐
quency range of 0.1–1.0×105 Hz using an ac bias of 0 V vs Ag/AgCl
without visible light irradiations in an aqueous solution containing
K3[Fe(CN)6] (1 mmol/L), K4[Fe(CN)6] (1 mmol/L) and KCl (0.1 mol/L).

414
Xinglin Wang et al. / Chinese Journal of Catalysis 42 (2021) 409–416
proposed in the light initiated hydrothiolation reactions over
Table 3
ZnIn2S4, the reduction of the protons by the photogenerated
electrons to produce the hydrogen consumes the protons
[47,48], which is a detrimental side reaction to the light initiat‐
ed hydrothiolation reactions and should be suppressed. There‐
fore, the loading of the cocatalysts on the surface ZnIn2S4 have
dual functions. First, the loading of the cocatalyst can improve
the efficiency on the photogeneration of the thiyl radicals, due
to enhanced separation and transportation of the pho‐
togenrated charge carriers, which is beneficial for the light ini‐
tiated hydrothiolation reaction. On the contrary, the loading of
the the cocatalyst also promotes the photocatalytic hydrogen
evolution, which is detrimental to the light initiated hydrothio‐
lation reaction. Therefore, a suitable cocatalyst to promote the
light initiated hydrothiolations over ZnIn2S4 should be able to
improve the separation and transportation of the photogener‐
ated charge carriers in ZnIn2S4, but itself cannot act as the ac‐
tive sites for hydrogen evolution, as that observed over Ir2S3, as
shown in Scheme 1.
Light initiated hydrothiolation between phenylacetylene and
1‐dodecanethiol over Ir2S3/ZnIn2S4, MoS2/ZnIn2S4, Pd/ZnIn2S4,
NiS/ZnIn2S4 and bare ZnIn2S4.
Conversion a
Yield b (%) H2 (μmol)
Entry
Catalyst
1
2
3
4
5
0.5 mol% Ir2S3/ZnIn2S4
0.5 mol% MoS2/ZnIn2S4
0.5 mol% Pd/ZnIn2S4
0.5 mol% NiS/ZnIn2S4
ZnIn2S4
79
55
60
41
58
76
54
59
39
56
0.7
13.2
1.9
3.9
—
Reaction conditions: phenylacetylene (0.12 mmol), 1‐dodecanethiol
(0.1 mmol), cat. (10 mg), CH3OH (4 mL), visible light irradiation for 15 h;
a Conversion was calculated based on phenylacetylene. b The amount of
the products was calculated based on GC and GC‐MS analyses.
as evidenced from the smaller radius on their EIS Nyquist plots
as compared with bare ZnIn2S4, although NiS is not as efficient
as the other three cocatalysts (Ir2S3, MoS2 and Pd) (Fig. 6).
However, all the three cocatalysts (MoS2, Pd and NiS) loaded do
not promote the hydrothiolation reaction between phenyla‐
cetylene and 1‐dodecanethiol. Among them, MoS2/ZnIn2S4 and
Pd/ZnIn2S4 show comparable performance as that over bare
ZnIn2S4, while the loading of NiS even lower the activity for
light initiated hydrothiolation reaction (Table 3). The obvious
inconsistent between the catalytic performance and the results
from the EIS Nyquist plots clearly indicated that, in addition to
the improved efficiency in the generation of thiyl radicals, there
is other factors influencing the performance of light initiated
hydrothiolation reaction over these cocatalysts loaded ZnIn2S4
nanocomposites.
In the light initiated hydrothiolation reactions over these
cocatalysts loaded ZnIn2S4 nanocomposites, we also notice that
varied amount of hydrogen were generated, although no de‐
tectable hydrogen evolved over bare ZnIn2S4, indicating that
the loading of all the cocatalysts also promotes the hydrogen
evolution. In addition, the amount of hydrogen evolved follows
an order of MoS2/ZnIn2S4> NiS/ZnIn2S4> Pd/ZnIn2S4>
Ir2S3/ZnIn2S4, a result not unexpected since both MoS2 and NiS
have been previously demonstrated to be good cocatalysts for
photocatalytic hydrogen evolution over ZnIn2S4. As previously
3. Conclusions
In conclusion, the loading of Ir2S3 on the surface of ZnIn2S4
was found to promote the light initiated thiol‐ene and thiol‐yne
reactions. The superior performance of Ir2S3/ZnIn2S4
nanocomposite for the light initiated hydrothiolation reactions
can be ascribed to an improved efficiency on the
photogeneration of the thiyl radicals by loading of Ir2S3 as well
as its inactivity for photocatalytic hydrogen evolution, a side
reaction to the light initiated hydrothiolation reaction over
ZnIn2S4. This study provides an efficient and green strategy to
synthesize thiolated products via the hydrothiolation of
unsaturated hydrocarbons (alkenes and alkynes) with thiols
over a semiconductor‐based photocatalyst under visible light.
This study also provides some guidances for the design and
development of photocatalytic systems for light induced
organic syntheses.
References
[1] C. Shen, P. Zhang, Q. Sun, S. Bai, T. S. A. Hor, X. Liu, Chem. Soc. Rev.,
2015, 44, 291–314.
[2] N. Nowrouzi, M. Abbasi, H. Latifi, Chin. J. Catal., 2016, 37,
1550–1554.
[3] V. Maffeis, R. O. McCourt, R. Petracca, O. Laethem, A. Camisasca, P.
E. Colavita, S. Giordani, E. M. Scanlan, ACS Appl. Nano Mater., 2018,
1, 4120−4126.
[4] C. Cao, L. R. Fraser, J. A. Love, J. Am. Chem. Soc., 2005, 127,
17614–17615.
[5] Y. Yang, R. M. Rioux, Chem. Commun., 2011, 47, 6557–6559.
[6] Y. Yang, R. M. Rioux, Green Chem., 2014, 16, 3916–3925.
[7] A. A. Festa, L. G. Voskressensky, E. V. Van der Eycken, Chem. Soc.
Rev., 2019, 48, 4401–4423.
[8] X. Deng, Z. Li, H. Garcia, Chem. Eur. J., 2017, 23, 11189–11209.
[9] Y. Zhao, G. I. N. Waterhouse, G. Chen, X. Xiong, L. Wu, C. Tung, T.
Zhang, Chem. Soc. Rev., 2019, 48, 1972–2010.
Scheme 1. Promoting mechanism by loading Ir2S3 for visi‐
ble‐light‐initiated hydrothiolations over ZnIn2S4.
[10] J. Kou, C. Lu, J. Wang, Y. Chen, Z. Xu, R. S. Varma, Chem. Rev., 2017,
117, 1445–1514.

Xinglin Wang et al. / Chinese Journal of Catalysis 42 (2021) 409–416
415
Graphical Abstract
Chin. J. Catal., 2021, 42: 409–416 doi: 10.1016/S1872‐2067(20)63660‐9
Efficient visible light initiated hydrothiolations of alkenes/alkynes over Ir2S3/ZnIn2S4: Role of Ir2S3
Xinglin Wang, Yuanyuan Li, Zhaohui Li 
Fuzhou University
H2
e - e -
Hydrothiolated Products
h+ h+
Superior
Ir2S3/ZnIn2S4
performance
Roles of Ir2S3
 Improved photogeneration of RS•
 Inactive for H2 evolution
Ir2S3/ZnIn2S4 nanocomposites were obtained by one‐pot solvothermal method, and the loading of Ir2S3 on the surface of ZnIn2S4 was
found to promote the light initiated thiol‐ene and thiol‐yne reactions.
[11] H. Hao, X. Lang, ChemCatChem, 2019, 11, 1378–1393.
[12] X. J. Lang, W. H. Ma, C. C. Chen, H. W. Ji, J. C. Zhao, Acc. Chem. Res.,
2014, 47, 355–363.
[27] M. Hao, X. Deng, L. Xu, Z. Li, Appl. Catal. B, 2019, 252, 18–23.
[28] Z. Lei, W. You, M. Liu, G. Zhou, T. Takata, M. Hara, K. Domen, C. Li,
Chem. Commun., 2003, 2142–2143.
[13] G. Palmisano, V. Augugliaro, M. Pagliaro, L. Palmisano, Chem.
Commun., 2007, 3425–3437.
[29] L. Wei, Y. Chen, L. Ye, Z. Li, Appl. Catal. B, 2014, 144, 521–527.
[30] B. Xu, P. He, H. Liu, P. Wang, G. Zhou, X. Wang, Angew. Chem. Int.
Ed., 2014, 53, 2339–2343.
[31] B. Wang, Z. Deng, X. Fu, C. Xu, Z. Li, Appl. Catal. B, 2018, 237,
970–975.
[32] J. Healy, T. Rasmussen, S. Miller, I. R. Booth , S. J. Conway, Org.
Chem. Front., 2016, 3, 439–446
[33] M. Lo Conte, S. Pacifico, A. Chambery, A. Marra, A. Dondoni, J. Org.
Chem., 2010, 75, 4644–4647.
[34] J. Yang, D. Wang, H. Han, C. Li, Acc. Chem. Res., 2013, 46,
1900–1909.
[35] J. Ran, J. Zhang, J. Yu, M. Jaroniec, S. Z. Qiao, Chem. Soc. Rev., 2014,
43, 7787–7812.
[36] E. Y. X. Chen, T. J. Marks, Chem. Rev., 2000, 100, 1391–1434.
[37] L. Wei, Y. Chen, J. Zhao, Z. Li, Beilstein J. Nanotechnol., 2013, 4,
949–955.
[14] G. Zhang, C. Bian, A. Lei, Chin. J. Catal., 2015, 36, 1428–1439.
[15] O. O. Fadeyi, J. J. Mousseau, Y. Feng, C. Allais, P. Nuhant, M. Chen, B.
Pierce, R. Robinson, Org. Lett., 2015, 17, 5756–5759.
[16] M. Teders, C. Henkel, L. Anhaeuser, F. Strieth‐Kalthoff, A.
Gómez‐Suárez, R. Kleinmans, A. Kahnt, A. Rentmeister, D. Guldi, F.
Glorius, Nat. Chem., 2018, 10, 981.
[17] E. L. Tyson, M. S. Ament, T. P. Yoon, J. Org. Chem., 2013, 78,
2046–2050.
[18] M. H. Keylor, J. E. Park, C. J. Wallentin, C. R. J. Stephenson, Tetrahe‐
dron, 2014, 70, 4264–4269.
[19] S. S. Zalesskiy, N. S. Shlapakov, V. P. Ananikov, Chem. Sci., 2016, 7,
6740–6745.
[20] V. T. Bhat, P. A. Duspara, S. Seo, N. S. B. Abu Bakar, M. F. Greaney,
Chem. Commun., 2015, 51, 4383–4385.
[21] Y. Li, J. Cai, M. Hao, Z. Li, Green Chem., 2019, 21, 2345–2351.
[22] L. Benati, L. Capella, P. C. Montevecchi, P. Spagnolo, J. Org. Chem.,
1995, 60, 7941–7946.
[38] B. Wang, Y. Ding, Z. Deng, Z. Li, Chin. J. Catal., 2019, 40, 335–342.
[39] R. Shen, L. Zhang, X. Chen, M. Jaroniec, N. Li, X. Li, Appl. Catal. B,
2020, 266, 118619.
[23] N. ten Brummelhuis, C. Diehl, H. Schlaad, Macromolecules, 2008,
41, 9946–9947.
[24] K. Griesbaum, Angew. Chem. Int. Ed., 1970, 9, 273–287.
[25] J. Justynska, Z. Hordyjewicz, H. Schlaad, Polymer, 2005, 46,
12057–12064.
[40] D. Ren, R. Shen, Z. Jiang, X. Lu, X. Li, Chin. J. Catal., 2020, 41, 31–40.
[41] R. Shen, J. Xie, Q. Xiang, X. Chen, J. Jiang, X. Li, Chin. J. Catal., 2019,
40, 240–288.
[42] Z. W. Zhang, Q. H. Li, X. Q. Qiao, D. Hou, D. S. Li, Chin. J. Catal., 2019,
40, 371–379.
[26] L. Herczynska, L. Lestel, S. Boileau, J. Chojnowski, S. Polowinski,
Eur. Polym. J., 1999, 35, 1115–1122.
[43] B. Chai, C. Liu, C. Wang, J. Yan, Z. Ren, Chin. J. Catal., 2017, 38,
2067–2075.

416
Xinglin Wang et al. / Chinese Journal of Catalysis 42 (2021) 409–416
[44] L. Ye, J. Fu, Z. Xu, R. Yuan, Z. Li, ACS Appl. Mater. Interfaces, 2014, 6,
3483–3490.
[47] A. P. M. Robertson, M. F. Haddow, I. Manners, Inorg. Chem., 2012,
51, 8254–8264
[45] P. Kalisman, Y. Kauffmann, L. Amirav, J. Mater. Chem. A, 2015, 3,
3261–3265.
[48] X. H. Yang, R. T. Davison, S. Z. Nie, F. A. Cruz, T. M. Tristan, V. M.
Dong, J. Am. Chem. Soc., 2019, 141, 3006–3013.
[46] L. Xu, Deng X, Z. Li, Appl. Catal. B, 2018, 234, 50–55.
Ir2S3/ZnIn2S4催化下可见光诱导发生的烯烃/炔烃的高效硫氢化反应: Ir2S3的作用
王星林, 李媛媛, 李朝晖
福州大学化学学院, 能源与环境光催化国家重点实验室光催化研究室, 福建福州350116
摘要: C–S键的构建在化学中具有非常重要的意义. 利用硫醇和烯烃/炔烃的硫氢化反应来构建C‒S键是一种绿色、可持续
和低成本的方法. 本文以ZnCl2, InCl3, 硫代乙酰胺为前驱体, 在微量IrCl3存在条件下, 通过一步溶剂热法制备得到了含有不
同Ir摩尔比(0.5 mol%, 1 mol%和2 mol%)的Ir2S3/ZnIn2S4纳米复合材料, 并考察了它在可见光下诱导烯烃/炔烃的硫氢化反应
中的催化性能. 以苄基硫醇和苯乙炔的硫氢化反应为模型反应, 发现在ZnIn2S4中引入微量的Ir2S3可明显提升其性能, 其中
以0.5 mol% Ir2S3/ZnIn2S4为催化剂时反应性能最佳; 反应15 h后苄基硫醇的转化率为97%, 苄基苯乙烯基硫醚的产率为
95%, 明显高于以未修饰的ZnIn2S4为催化剂时的转化率和产率. 在反应中加入自由基捕获剂TEMPO之后可淬灭该反应, 表
明与未修饰的ZnIn2S4相同, 以Ir2S3/ZnIn2S4复合材料催化的硫氢化反应同样是由硫醇自由基诱发的反应. 这种微量Ir2S3对
ZnIn2S4上光诱导硫氢化反应的提升作用在所考察的多个系列底物的反应中都有不同程度的体现, 尤其对于一些空间体积
较大的底物, 其提升作用尤为明显, 表明微量Ir2S3的存在对ZnIn2S4上光诱导硫醇和烯烃/炔烃硫氢化反应的提升作用具有
普适性. 通过研究负载不同助催化剂(MoS2, NiS和Pd)的ZnIn2S4纳米复合材料在烯烃/炔烃硫氢化反应中的性能及其电化学
交流阻抗, 我们发现, Ir2S3的存在可促进ZnIn2S4上光生电子空穴的分离, 从而有利于巯基自由基的生成, 同时还抑制了副物
氢气的产生, 因此, 烯烃/炔烃的硫氢化反应性能显著提高. 该文提出了一种在可见光下利用半导体光催化来构建C‒S键的
绿色途径, 对于理解和设计新的光催化有机合成反应体系具有一定的指导意义.
关键词: 光催化; 硫化铱/ZnIn2S4; 烯烃; 炔烃; 硫氢化反应
收稿日期: 2020-05-19. 接受日期: 2020-06-25. 出版日期: 2021-03-05.
*通讯联系人. 电话/传真: (0591)22865855; 电子信箱: zhaohuili1969@yahoo.com
基金来源: 国家自然科学基金(21872031, U1705251); 闽江学者特聘教授科研启动基金.
本文的电子版全文由Elsevier出版社在ScienceDirect上出版(http://www.sciencedirect.com/science/journal/18722067).