Paired Electrocatalytic Oxygenation and Hydrogenation of Organic Substrates with Water as the Oxygen and Hydrogen Source

Article abstract of DOI:10.1002/anie.201903936

The use of water as an oxygen and hydrogen source for the paired oxygenation and hydrogenation of organic substrates to produce valuable chemicals is of utmost importance as a means of establishing green chemical syntheses. Inspired by the active Ni³⁺ intermediates involved in electrocatalytic water oxidation by nickel-based materials, we prepared NiB_x as a catalyst and used water as the oxygen source for the oxygenation of various organic compounds. NiB_x was further employed as both an anode and a cathode in a paired electrosynthesis cell for the respective oxygenation and hydrogenation of organic compounds, with water as both the oxygen and hydrogen source. Conversion efficiency and selectivity of ≥99 % were observed during the oxygenation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid and the simultaneous hydrogenation of p-nitrophenol to p-aminophenol. This paired electrosynthesis cell has also been coupled to a solar cell as a stand-alone reactor in response to sunlight.

Full text of DOI:10.1002/anie.201903936

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Accepted Article
Title: Paired electrocatalytic oxygenation and hydrogenation of organic
substrates using water as oxygen and hydrogen source
Authors: Licheng Sun, Peili Zhang, Xia Sheng, Xiaoyu Chen, Zhiyong
Fang, Jian Jiang, Mei Wang, Fusheng Li, Lizhou Fan,
Yansong Ren, Biaobiao Zhang, Brian Timmer, and Marten
Ahlquist
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To be cited as: Angew. Chem. Int. Ed. 10.1002/anie.201903936
Angew. Chem. 10.1002/ange.201903936
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http://dx.doi.org/10.1002/ange.201903936

10.1002/anie.201903936
Angewandte Chemie International Edition
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Paired electrocatalytic oxygenation and hydrogenation of organic
substrates using water as oxygen and hydrogen source
Peili Zhang,[a,b] Xia Sheng,[a] Xiaoyu Chen,[c] Zhiyong Fang,[b] Jian Jiang,[b] Mei Wang,[b] Fusheng Li,[b]
Lizhou Fan,[a] Yansong Ren,[a] Biaobiao Zhang,[a] Brian J.J. Timmer,[a] Mårten S.G.Ahlquist,[c] Licheng
Sun*[a,b]
Abstract: The use of water as an oxygen and hydrogen source for
the paired oxygenation and hydrogenation of organic substrates to
produce valuable chemicals is of utmost importance as a means of
establishing green chemical syntheses. Inspired by the active Ni3+
intermediates involved in electrocatalytic water oxidation by Ni-based
materials, we prepared NiBx as a catalyst and used water as the
oxygen source for the oxygenations of various organics. NiBx was
further employed as both an anode and cathode in a paired
electrosynthesis cell for the respective oxygenation and
hydrogenation of organic compounds, with water as both the oxygen
and hydrogen source. Conversions efficiencies and selectivities of
coupled attenuated total reflection infrared spectroscopy with NixB
as the catalyst.[3d] To date, the majority of literature reports have
focused on conversions efficiencies and selectivities, while the
water active process, the catalytic active sits and the oxygen atom
transfer mechanism are ambiguity. [3]
In electrocatalytic oxygenation reactions, protons are
generated as a by-product.[4] Recently, these reactions have been
paired with electrocatalytic hydrogen evolution reaction (HER) to
increase the energy conversion efficiency.[3] However, compared
with HER, the organic oxygenation reactions are kinetically
sluggish, especially in the late stages of the reaction, owing to the
decrease in reactant concentrations. Thus, both catalytic
efficiency and electron economy could be improved by pairing
organic oxygenation with a rate-matched organic hydrogenation
to create sustainable chemical synthesis strategies.[4]
≥99%
were achieved during the oxygenation of 5-
hydroxymethylfurfural to 2,5-furandicarboxylic acid and the
simultaneous hydrogenation of p-nitrophenol to p-aminophenol. This
paired electrosynthesis cell has also been coupled to a solar cell as a
stand-alone reactor in response to sunlight.
Herein, the electrocatalytic oxygen atom transfer mechanism
was investigated in 1 M KOH with NiBx (x = 0.40 ± 0.05) as
catalyst and the oxygenation of HMF to 2,5-furandicarboxylic acid
(FDCA) as a model reaction. Experiment results indicated that the
electrogenerated Ni3+ species are the active intermediates.
Furthermore, paired electrolysis system was constructed by
combining the electrocatalytic oxygenation of HMF to FDCA and
the hydrogenation of p-nitrophenol (p-NP) to p-aminophenol (p-
AP). Conversions efficiencies, selectivities and faradic efficiency
as high as ≥99% were achieved on both sides with water as
oxygen and hydrogen source. This paired electrolyser uses
electricity to drive the organic oxygenation and hydrogenation
reactions in aqueous solutions, without the need to handle
hazardous gaseous hydrogen or oxygen or to incorporate
external oxidants/ reductants.
The NiBx working electrode (WE) was prepared by
electroless plating for 2 hours with a nickel foam (NF) substrate
at 90 °C in NaOH aqueous solutions (pH 13.5) containing
Ni(Cl)2·6H2O (125 mM), ethanediamine (750 mM) and NaBH4 (55
mM).[5] The Ni:B atomic ratio (1:0.40 ± 0.05) was verified by
inductively coupled plasma optical emission spectroscopy and the
NiBx loading on the NF surface was 2.47 ± 0.10 mg cm2. Top-
view scanning electron microscopy (SEM) images showed that
NiBx was uniformly deposited on the NF to provide a rough
surface (Figures 1a, 1b). High-resolution transmission electron
microscopy (TEM) images (Figure 1c) suggested that the surface
particles were composed of amorphous nickel boride and nickel.
X-ray photoelectron spectroscopy (XPS) analysis confirmed that
Ni and B were the main components (Figure S1). The Ni 2p3/2
peak at 852.7 eV can be assigned to Ni0, while the B 1s peak at
187.8 eV can be assigned to B0, as expected for nickel borides.[6]
The weak B 1s hump at 192.1 eV and the O 1s peak at 532.5 eV
are due to small amounts of boron oxide (Figures 1j–l).[6b]
Water is an abundant resource on earth and is widely used as
either an oxygen or hydrogen source during naturally occurring
biosynthetic oxygenation and hydrogenation reactions.[1,2]
Inspired by natural systems, we consider water to represent an
ideal source of oxygen and hydrogen instead of high-cost H2 or
chemical oxidants/reductants for catalytic oxygenation and
hydrogenation in green chemical processes.
During the last decade, electrocatalytic oxygenation of
organic compounds to value-added products with water as
oxygen source has started to attract increased attention. Several
interesting electrocatalytic systems have been reported with
improving performance. Ni2P,[3a] Co-P, [3b] Ni3S2, [3c] NixB, [3d] NiFe
LDH, [3e] noble metals (Au and Pd) and their alloys[3f] are used as
efficient electrocatalysts for the oxidation of furanics and other
biomass-derived platform chemicals. Recently, Schuhmann
group provided new insight into the oxidation pathway of 5-
hydroxymethylfurfural (HMF) through operando electrochemistry
[a]
[b]
[c]
Dr. P. Zhang, Dr. X. Sheng, L. Fan, Dr. Y. Ren, Dr. B. Zhang, Dr.
B.J.J. Timmer, and Prof. L. Sun, Department of Chemistry, School of
Engineering Sciences in Chemistry, Biotechnology and Health, KTH
Royal Institute of Technology, 10044 Stockholm, Sweden E-mail:
lichengs@kth.se
Dr. P. Zhang, Z. Fang, J. Jiang, Prof. M. Wang, Dr. F. Li, and Prof. L.
Sun, State Key Laboratory of Fine Chemicals, Institute of Artificial
Photosynthesis, DUT-KTH Joint Education and Research Centre on
Molecular Devices, Dalian University of Technology, 116024 Dalian,
China
X. Chen and Dr. M.S.G. Ahlquist, Department of Theoretical
Chemistry & Biology, School of Engineering Sciences in Chemistry
Biotechnology and Health, KTH Royal Institute of Technology, 10691
Stockholm, Sweden
Supporting information for this article is given via a link at the end of the
document.
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10.1002/anie.201903936
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COMMUNICATION
Figure 2. (a) Raman spectra of NiBx@NF at 0.50 V vs. SHE in 1 M KOH (red)
and the as-prepared NiBx@NF (black); (b) Open-circuit potential versus time
technique used to investigate the lifetime of the electrogenerated Ni3+ species
on the surface of NiBx@NF in 1 M KOH with (red curve) and without (blue curve)
HMF; (c) Changes in Raman spectra of NiBx@NF after the injection of HMF into
the electrolyte.
of FFCA to FDCA occurs at an Eo of 0.109 V vs. SHE. The
reduction potential of Ni3+/Ni2+ is approximately 0.50 V vs. SHE.[9]
Therefore, based on DFT calculations, the oxidizing ability of Ni3+
would be expected to drive each step during the oxidation of HMF
to FDCA. Indeed, chemical oxygenation of HMF with the Ni3+-
complex Ni3O2(OH)4[10] (Figure S4) showed a high yield (≥ 99 %)
of FDAC in aqueous media. The powder X-ray diffraction (XRD)
pattern of the Ni material after oxygenation demonstrated the
formation of Ni(OH)2, which is indicative of the Ni3+ to Ni2+ redox
process responsible for the oxidation (Figure S4).
Figure 1. (a,b) SEM images and (c) TEM image of the as-prepared NiBx@NF;
(d) TEM image and (e–i) elemental mapping of NiBx@NF after controlled
potential electrolysis at 0.50 V vs. SHE; (j–l) high-resolution (j) Ni 2p, (k) B 1s
and (l) O 1s XPS spectra obtained from the as-prepared NiBx@NF; (m–o) high-
resolution (m) Ni 2p, (n) B 1s and (o) O 1s XPS spectra obtained from the
NiBx@NF after controlled potential electrolysis at 0.50 V vs. SHE.
The activity of the electro-generated Ni3+ toward the
oxygenation of HMF in 1 M KOH was further verified by an open-
circuit potential versus time (OCPT) experiment. The change in
the EOCP reflects variations in the WE surface that, in turn, depend
Linear sweep voltammetry (LSV) and in situ Raman
spectroscopy were used to study the formation of the Ni3+ species.
The LSV sweep of NiBx@NF in 1 M KOH shows an oxidation peak
at 0.50 V vs. SHE, corresponds to the Ni2+/Ni3+ oxidation (Figure
S2). After electrolysis at 0.50 V vs. SHE, the surface of the
NiBx@NF was analysed by TEM (Figures 1d – i) and XPS
(Figures. 1m–o). TEM images and TEM mapping demonstrated
that a new shell was generated on the surface of the NiBx particles
(Figures 1d, 1i), while Ni 2p3/2, O 1s and B 1s XPS data indicated
that this shell was composed of a mixture of Ni oxide and Ni
hydroxide (Figures 1m–o). Raman spectra of the NiBx@NF at
0.50 V vs. SHE showed the emergence of a Ni3+-O bending peak
at 471 cm1 and a Ni3+-O stretching peak at 554 cm1,
demonstrating that NiOOH (Ni3+) was the electrogenerated
intermediate (Figure 2a).[7]
on changes in the active species at the electrode-solution
[11]
interface.
In this work, EOCP is associated with the anodic
reaction occurring at the WE surface. The electro-generated Ni3+
species correspond to an EOCP of 0.50 V vs. SHE, while the Ni2+
species correspond to an EOCP of −0.01 V vs. SHE. The surface
Ni was oxidized to Ni3+ at 0.50 V vs. SHE (Ni(OH)2 + OH− →
NiOOH + H2O + e−), followed by a spontaneous transition to Ni2+
(NiOOH + H2O + e− → Ni(OH)2 + OH−) with a lifetime of 1700 s
(Figure 2b). A control OCPT experiment showed that the lifetime
of the electro-generated Ni3+ was shortened to 200 s upon adding
HMF to the electrolyte (Figures 2b, 2c). This accelerated
quenching indicates that the electrochemical generated Ni3+ is the
active intermediate during the oxygenation of HMF.
Initially, the oxidizability of Ni3+ for HMF oxygenation was
The effect of water on the catalytic oxygenation of HMF with
NiBx@NF was assessed by performing trials in acetonitrile
(Figure S5). The blank cyclic voltammogram (CV) curve obtained
with NiBx@NF in acetonitrile showed a Faradaic silent curve
before 2.2 V vs. SHE, indicates difficulty in forming Ni3+ species
without water. The subsequent addition of HMF gave an identical
curve to that produced during the blank CV, indicating that HMF
oxygenation did not proceed without the Ni3+ species. A control
experiment with NiBx@NF in acetonitrile with water produced a
water oxidation current at 1.90 V vs. SHE, demonstrating the
formation of Ni3+. When water was added together with HMF, a
current increase was observed at 1.70 V vs. SHE, assigned to the
oxygenation of HMF. These results show that HMF was
oxygenated, with water serving as the oxygen source, and that
Ni3+ is an essential intermediate.
computationally
and
experimentally
investigated.
The
oxygenation of HMF to FDCA is a three-step process, includes
the oxidation of the hydroxyl and aldehyde groups to carboxylic
acids (Figure S3).[8] The oxidation of HMF to FDCA can proceed
via two pathways, distinguished by the primary oxidation of the
hydroxyl or carbonyl functionality (Figure S3a). The standard
potential (Eo) for each step on both pathways were estimated
using density functional theory (DFT) calculations (Figure S3b).
HMF converts to 5-hydroxymethyl-2-furancarboxylic acid (HMFA)
with an Eo of 0.098 V vs. SHE, while the competitive reaction from
HMF to the dialdehyde 2,5-diformylfuran (DFF) has an Eo of
−0.187 V vs. SHE. Further oxidation of the DFF and HMFA leads
to the formation of 5-formyl-2-furancarboxylic acid (FFCA) with Eo
of 0.119 V and −0.167 V vs. SHE, respectively. The final oxidation
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Figure 3. (a) LSV curves obtained from NiBx@NF in a 1 M KOH with and
without HMF (10 mM); (b) LSV curves of a glassy carbon plate in a 1 M KOH
with and without 10 mM HMF (scan rate, 5 mV s1); (c) the HMF, FDCA and
intermediates concentrations vs. electrolysis time; (d) HPLC chromatograms
acquired at various electrolysis times.
Figure 4. (a) LSV curves obtained from NiBx@NF in 1 M KOH in the absence
and presence of 10 mM p-NP, at a scan rate of 5 mV s1; (b) polarization curves
for a glassy carbon plate in 1 M KOH in the absence and presence of 10 mM p-
NP, at a scan rate of 5 mV s1; (e) [p-NP] and [p-AP] vs. electrolysis time; (f)
HPLC chromatograms acquired at various electrolysis time points.
Based on the previous results, we concluded that the
electrocatalytic oxygenation of HMF with NiBx@NF as WE and
water as an oxygen source occurs through a two-step oxygen
transfer mechanism (Figure S6). First, Ni2+ is electro-oxidized to
Ni3+ with a newly bonded OH– originating from water. Second, the
resulting Ni3+ species, reacts with HMF, DFF and/or HMFA to
efficiency of the electrocatalytic HMF oxygenation was
approximately 99.5 ± 0.5%, based on the electrolysis and the
theoretical charges for the formation of FDCA (Figure S8).
To enhance atom utilization, a cathodic reaction is necessary
to consume the protons generated during the oxygenation of
HMFThe hydrogenation of nitro-compounds to their
produce FDCA, along with the regeneration of Ni2+. In this process, corresponding amines is important for the synthesis of fine
water is the only oxygen source.
chemicals, such as dyes and pigments.[13] In subsequent trials,
the hydrogenation of p-NP to p-AP was used as a model reaction
in conjunction with NiBx/NF as the WE and water as the hydrogen
source.
The electrocatalytic performance of NiBx@NF toward HMF
oxygenation in 1 M KOH is summarized in Figure 3. The LSV
curve of NiBx@NF without HMF shows a Ni2+/Ni3+ oxidation peak
at 0.50 V vs. SHE, followed by a silent region of 0.55–0.75 V vs.
SHE, and the OER beyond 0.75 V vs. SHE.[12] To investigate the
extent to which oxygenation was catalyzed, 10 mM HMF was
added to the electrolyte. The LSV curve shows a similar Ni2+/Ni3+
process at 0.50 V vs. SHE, followed by a significant enhancement
at 0.60 V vs. SHE with a peak current density of 40 mA cm−2,
which is attributed to the HMF oxygenation reaction (Figure 3a).
It is evident that HMF oxygenation is favoured over the OER.
Furthermore, the current density beyond 0.70 V vs. SHE is
attributed to the superposition of HMF oxygenation and the OER.
Control experiments with a glassy carbon plate produced a
Faradaic silent region from 0.20 to 0.80 V vs. SHE both with and
without the HMF (Figure 3b). These results indicate that the
NiBx@NF promoted HMF oxygenation through a electrocatalytic
process. Further research showed that the peak current densities
at 0.60 V vs. SHE increased linearly along with increases in the
HMF concentration (Figures S7). These results suggest that the
oxygenation on the WE surface is a diffusion-controlled process.
Conversion, selectivity and Faradaic efficiency are
investigated during the oxygenation of HMF to FDCA by
chronoamperometry. A constant potential of 0.60 V vs. SHE was
applied during the electrolysis (Figure 3c, 3d). The reaction
process was monitored by high performance liquid
chromatography (HPLC). The results showed that HMF was 99.8
± 0.2% converted to FDCA after 100 min. DFF and FFCA were
identified by HPLC as intermediates. Overall, the oxygenation of
HMF to FDCA is a six electron process,[8,3d] and the Faradaic
The electro-catalytic hydrogenation of p-NP proceeds via
three two-electron-two-proton processes (Figure S9). Under
standard conditions, ΔG was found to be negative (∆G < 0) for
each step, indicating that the hydrogenation of p-NP is an
exergonic process. The reduction potentials for the continuous
reduction reactions are 0.603, 0.333 and 0.719 V vs. SHE (R2NO2
+ 2H+ + 2e– → R2NO + H2O, R2NO + 2H+ + 2e– → R2NHOH,
R2NHOH → R2NH + H2O, R2NH + 2H+ + 2e– → R2NH2, R2NO2 =
p-nitrophenol), and thus occur prior to hydrogen evolution on a
thermodynamic basis. These calculations demonstrate that the
reduction of nitrosamine to hydroxylamine requires the highest
potential of 0.333 V vs. SHE.
In 1 M KOH, NiBx/NF showed an onset potential of –0.90 V
vs. SHE for HER (Figure 4a). After the addition of p-NP, the LSV
curve exhibited an onset potential of 0.60 V vs. SHE, followed
by a current density of 40 mA cm2 at 0.83 V vs. SHE (0 V vs.
RHE). The increased current density beyond 0.90 V vs. SHE is
attributed to the superposition of the hydrogenation reaction and
the HER. These results indicate that the targeted nitro-group
hydrogenation occurred prior to the HER, and that a high Faradaic
efficiency can readily be achieved through controlling the applied
potential. Control experiments with a glassy carbon electrode
showed a similar activity toward p-NP hydrogenation with an
onset potential of 0.65 V vs. SHE (Figure 4b). It is evident that
the hydrogenation of p-NP in 1 M KOH proceeds on an electro-
[14]
reduction mechanism.
Furthermore, a linear relationship was
observed between the p-NP concentration and the corresponding
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An applied potential of 1.40 V was used for further
chronoamperometric tests. In the electrolysis process, the
Faradaic current density gradually decreased to 0 within 240 min,
with a charge build-up of 238 C (Figure 5c). The starting
substrates (HMF and p-NP) were consumed with ≥99%
conversion to the corresponding products (Figures 5d, 5e). The
expected intermediates FFCA and DFF, were also detected by
HPLC (Figure 5d). Furthermore, a Faradaic efficiency of ≥99%
was achieved for each side.
The design of the paired electrolyser is scalable to meet
different requirements. A simple photoelectrochemical-driven
oxygenation and hydrogenation device was created by
connecting solar cells (1.5 V silicon solar panel) and the paired
electrolyser in series (Figure S12). This photovoltaic integrated
electrolyser demonstrated the simultaneous oxygenation of HMF
and hydrogenation of p-NP in an aqueous solution under outdoor
sunlight with high conversion and selectivity (≥99%). In addition,
high conversion and selectivity were also observed when HMF
was replaced with furan-2-carbaldehyde, furan-2-ylmethanol,
pyridine-4-ylmethanol and 4-(hydroxymethyl)phenol as the
compounds undergoing oxygenation, and when p-NP was
replaced with m-NP, o-NP, 4-nitrobenzonitrile and 1-ethynyl-4-
nitrobenzene (Figure S13, S14 and Table S1).
In summary, we have developed a paired electrochemical
system for the oxygenation and hydrogenation of organics to
replace the chemical-driven stoichiometric reactions using
sacrificial reagents. Water was found to be essential as the
oxygen and hydrogen source for these redox reactions in the
paired electrolyser. The as-designed electrochemical cell exhibit
high conversion, selectivity and Faradaic efficiency values at both
the anode and cathode simultaneously, without the involvement
of oxygen and hydrogen. As an example, a conversion efficiency
of ≥99% was achieved during the oxygenation of HMF to FDCA
and the hydrogenation of p-NP to p-AP. The experimental results
show that this paired electrolyser can be extended to other
organic substrates. This new (photo)electrocatalytic cell system is
very promising and should have practical applications in future
green chemical systems using electricity or sunlight as the energy
input and water as both the oxygen and hydrogen sources.
Figure 5. (a) Schematic representation of the paired electrochemical cell; (b)
the LSV curves obtained from the paired electrolyser in 1.0 M KOH in the
absence and presence of organic reactants (scan rate, 5 mV s1); (c) current–
time and charge–time transients during constant potential electrolysis at 1.40 V;
(d) results from analysis of the anode side at various charges; (e) results from
analysis of the cathode side at various charges.
current density (Figure S10), indicating a molecular diffusion
reaction process. The catalytic properties of NiBx@NF during the
hydrogenation
of
p-NP
were
further
explored
by
chronoamperometry. A conversion and selectivity of ≥99% was
achieved after 50 min at the applied potential of 0.83 V vs. SHE
(Figures 4c, 4d, S11). During the catalytic process, no
intermediates were observed by HPLC. A Faradaic efficiency of
approximately 99% was calculated by comparing the charge
consumed in the production of p-AP with the integrated current.
Paired electrolysis combines two desirable half-reactions to
maximize energy efficiency and the formation of useful
products.[15] As previously described, the as-prepared NiBx@NF
exhibited promising catalytic performance during the
electrocatalytic oxygenation and hydrogenation half reactions
under the same conditions. Hence, we integrated these two half-
reactions in an electrolyser to realize paired electrolysis, using the
full potential of water as both an oxygen and hydrogen source
(Figure 5a). The catalytic activities of NiBx@NF during HMF
oxygenation and p-NP hydrogenation in the paired electrolyser
were further evaluated by acquiring polarization curves and
electrolysis (Figure 5). In the absence of HMF and p-NP,
NiBx@NF exhibited HER activity beyond 1.65 V (Figure 5b). The
LSV curve obtained during the paired oxygenation of HMF and
hydrogenation of p-NP (Figure 5b) exhibited an onset potential of
1.10 V and reached a plateau of 50 mA cm2 at 1.5 V. These
results indicate that the paired reactions proceeded preferentially
rather than the hydrogen evolution.
Experimental Section
All electrochemical experiments were performed with a CH Instrument
660E potentiostat. The electrochemical cell contained the sample as a WE,
a platinum foil (4 cm2) as an auxiliary electrode and Hg/HgO (1 M KOH,
Tjaida) as a reference electrode (Eo
= 0.098 V vs. SHE). The
Hg/HgO
reference electrodes were calibrated by measuring the standard hydrogen
electrode (SHE) potential. Potentials were converted to SHE via the Nernst
equation: ESHE = EHg/HgO + 0.059 pH + EoHg/HgO. The internal resistance
between the reference and WE (Ru) was determined by the automatic
current interrupt (Ru = 0.8 ± 0.1 Ω). iR compensation during LSV sweeps
was performed using the automatic current interrupt method, with a value
of 75%×Ru. Chronopotentiometry measurements were performed under
Argon atmosphere (unless stated otherwise) with an H-type cell to
evaluate the catalytic activity. Nafion® 117 membranes were used to
separate the anodic and cathodic compartments.
Acknowledgements
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10.1002/anie.201903936
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COMMUNICATION
We acknowledge the financial support of this work by Swedish
Energy Agency, the Knut & Alice Wallenberg Foundation (KAW
2016.0072), the Swedish Research Council (2017-00935), the
National Basic Research Program of China (973 Program,
2014CB239402) and the Fundamental Research Funds for the
Central Universities (DUT17RC(3)083).
Keywords: electrosynthesis • water • oxygenation •
hydrogenation • green chemical synthesis
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10.1002/anie.201903936
Angewandte Chemie International Edition
COMMUNICATION
Layout 1:
COMMUNICATION
NiBx@NF was employed as both an
anode and cathode in a paired
electrosynthesis cell for the
respective oxygenation and
hydrogenation of organics, with
water as both the oxygen and
hydrogen source. Conversions
efficiencies and selectivities of ≥99%
were achieved during the
Peili Zhang, Xia Sheng, Xiaoyu Chen,
Zhiyong Fang, Jian Jiang, Mei Wang,
Fusheng Li, Lizhou Fan, Yansong
Ren, Biaobiao Zhang, Brian J.J.
Timmer, Mårten S.G.Ahlquist, Licheng
Sun*
Page No. – Page No.
Paired electrocatalytic oxygenation
and hydrogenation of organic
substrates using water as oxygen
and hydrogen source
oxygenation of 5-
hydroxymethylfurfural and the
simultaneous hydrogenation of p-
nitrophenol.
This article is protected by copyright. All rights reserved.