Yong Chen

The development of high-efficiency and low-cost catalysts for hydrogen release from chemical hydrogen-storage materials is essential for the hydrogen-economy paradigm. Herein, we report a facile and controllable method to fabricate a series of Co-doped nickel phosphides and their corresponding nanohybrids with graphene oxide (GO) as highly efficient, robust and noble-metal-free catalysts for ammonia borane hydrolysis. The incorporation of Co into Ni2P effectively optimizes the electronic structures of Ni2−xCoxP catalysts to enhance their interaction with AB and simultaneously facilitate the hydroxyl activation of AB, resulting in the reduction of the reaction energy barrier and thus substantial improvement of the catalytic rate.

Self-Supported Cedarlike Semimetallic Cu3P Nanoarrays as a 3D High-Performance Janus Electrode for Both Oxygen and Hydrogen Evolution under Basic Conditions

Co-reporter:Chun-Chao Hou, Qian-Qian Chen, Chuan-Jun Wang, Fei Liang, Zheshuai Lin, Wen-Fu Fu, and Yong Chen

ACS Applied Materials & Interfaces 2016 Volume 8(Issue 35) pp:23037

Publication Date(Web):August 25, 2016

DOI:10.1021/acsami.6b06251

There has been strong and growing interest in the development of cost-effective and highly active oxygen evolution reaction (OER) electrocatalysts for alternative fuels utilization and conversion devices. We report herein that semimetallic Cu3P nanoarrays directly grown on 3D copper foam (CF) substrate can function as effective electrocatalysts for water oxidation. Specifically, the surface oxidation-activated Cu3P only required a relatively low overpotential of 412 mV to achieve a current density of 50 mA cm–2 and displayed a small Tafel slope of 63 mV dec–1 in 0.1 M KOH solution, on account of the collaborative effect of large roughness factor (RF) and semimetallic character. Following that, investigations into the mechanism revealed the formation of a unique active phase during the water oxidation process in which conductive Cu3P was the core covered with a thin copper oxide/hydroxide layer. Moreover, this Cu3P 3D electrode was also applied to the hydrogen evolution reaction (HER) and showed good catalytic performance and stability under the same basic conditions.Keywords: copper phosphide; electrocatalysis; hydrogen evolution; oxygen evolution; water splitting

Incorporation of a [Ru(dcbpy)(bpy)2]2+ photosensitizer and a Pt(dcbpy)Cl2 catalyst into metal–organic frameworks for photocatalytic hydrogen evolution from aqueous solution

Co-reporter:Chun-Chao Hou, Ting-Ting Li, Shuang Cao, Yong Chen and Wen-Fu Fu

Journal of Materials Chemistry A 2015 vol. 3(Issue 19) pp:10386-10394

Publication Date(Web):08 Apr 2015

DOI:10.1039/C5TA01135C

A molecular photosensitizer [Ru(dcbpy)(bpy)2]2+ (dcbpy = 2,2′-bipyridyl-5,5′-dicarboxylic acid) and a proton reduction catalyst Pt(dcbpy)Cl2 were successfully incorporated into a highly robust metal–organic framework (MOF) of Zr(IV)6O4(OH)4(bpdc)6 (bpdc = 4,4′-biphenyldicarboxylic acid) by making use of a mix-and-match approach. The molecular integrity of the Ru and Pt complexes within the MOFs was demonstrated by a variety of techniques, including XRD, BET, TGA, SEM, TEM, HAADF-STEM, EDX, DRUS and XPS. This di-component Ru–Pt@UIO-67 MOF assembly allows a facile arrangement of the photosensitizer and the reduction catalyst with close spatial proximity, promotes the electron transfer between them, and thus leads to a significantly improved hydrogen evolution activity in aqueous solution at pH 5.0 upon visible light irradiation. This Ru–Pt@UIO-67 system represents the first example of MOFs functionalized with two different transition metal complexes, which can be used as a photosensitizer and catalyst, respectively, for hydrogen generation from water.

Enhanced photocatalytic H2-evolution by immobilizing CdS nanocrystals on ultrathin Co0.85Se/RGO–PEI nanosheets

Co-reporter:Shuang Cao, Yong Chen, Lei Kang, Zheshuai Lin and Wen-Fu Fu

Journal of Materials Chemistry A 2015 vol. 3(Issue 36) pp:18711-18717

Publication Date(Web):19 Aug 2015

DOI:10.1039/C5TA04910E

We herein report a novel noble-metal-free photocatalytic H2-production system by immobilizing CdS nanocrystals on ultrathin Co0.85Se/graphene nanosheets. The well-designed composite material was prepared by a simple solvothermal method and achieved a dramatically enhanced H2-evolution performance when compared with other bulk counterparts. Under optimal conditions, the H2-evolution efficiency can reach up to 17.60 μmol mg−1 h−1 after 10 h of LED visible light irradiation, which is comparable to that of noble Pt nanoparticles (18.60 μmol mg−1 h−1). It is proposed that the unusual catalytic rate arises from the special nanostructure of Co0.85Se and a positive synergetic effect between Co0.85Se and graphene. The results show that the ultrathin Co0.85Se which possesses a half-metallic character is a promising noble-metal-free cocatalyst for practical photocatalytic hydrogen production application.

Cobalt phosphide as a highly active non-precious metal cocatalyst for photocatalytic hydrogen production under visible light irradiation

Co-reporter:Shuang Cao, Yong Chen, Chun-Chao Hou, Xiao-Jun Lv and Wen-Fu Fu

Journal of Materials Chemistry A 2015 vol. 3(Issue 11) pp:6096-6101

Publication Date(Web):03 Feb 2015

DOI:10.1039/C4TA07149B

Cobalt phosphide (Co2P) is found, for the first time, to be a novel cocatalyst for efficient photocatalytic hydrogen evolution for a system containing CdS nanorods as a photocatalyst and DL-mandelic acid as an electron donor in water. Under optimal conditions, the H2-production rate can reach up to 19373 μmolh−1 g−1 after 10 h of LED light irradiation. Meanwhile, DL-mandelic acid can be oxidized to benzoylformic acid by the photo-generated holes of CdS nanorods, providing a green and economic way to synthesize benzoylformic acid from DL-mandelic acid.

Spectacular photocatalytic hydrogen evolution using metal-phosphide/CdS hybrid catalysts under sunlight irradiation

Co-reporter:Shuang Cao, Yong Chen, Chuan-Jun Wang, Xiao-Jun Lv and Wen-Fu Fu

Chemical Communications 2015 vol. 51(Issue 41) pp:8708-8711

Publication Date(Web):16 Apr 2015

DOI:10.1039/C5CC01799H

A highly efficient and robust heterogeneous photocatalytic hydrogen evolution system was established for the first time by using the CoP/CdS hybrid catalyst in water under solar irradiation. The H2-production rate can reach up to 254000 μmol h−1 g−1 during 4.5 h of sunlight irradiation, which is one of the highest values ever reported on CdS photocatalytic systems in the literature.

Ultrafine CoP Nanoparticles Supported on Carbon Nanotubes as Highly Active Electrocatalyst for Both Oxygen and Hydrogen Evolution in Basic Media

Co-reporter:Chun-Chao Hou, Shuang Cao, Wen-Fu Fu, and Yong Chen

ACS Applied Materials & Interfaces 2015 Volume 7(Issue 51) pp:28412

Publication Date(Web):December 7, 2015

DOI:10.1021/acsami.5b09207

The development of low-cost and highly active electrocatalysts for two half reactions: H2 and O2 evolution reactions (HER and OER), is still a huge challenge to realize water splitting. Herein, we report that CoP nanoparticles (NPs) can act as a bifunctional catalyst for both HER and OER. Particularly, ultrafine CoP NPs decorated on N-doped multiwalled carbon nanotube (MWCNT) exhibit remarkable catalytic performance for OER in 0.1 M NaOH aqueous solution, with a low onset overpotential of 290 mV, a Tafel slope of 50 mV dec–1, an overpotential (η) of 330 mV at 10 mA cm–2, and approximately 100% Faradaic efficiency, paralleling the performance of state-of-the-art Co-based OER catalysts including Co3O4, CoSe2, and Co–Pi. The hybrid catalyst is capable of maintaining a high catalytic current density for at least 10 h without any loss of catalytic activity. Meanwhile, the noble-metal-free catalyst also shows good activity and duarability for HER under the same basic condition.Keywords: cobalt phosphide; electrocatalysis; hydrogen evolution; oxygen evolution; water splitting

Long-Lived Excited States of Zwitterionic Copper(I) Complexes for Photoinduced Cross-Dehydrogenative Coupling Reactions

Co-reporter:Dr. Bin Wang;Dr. Deepak Prakash Shelar;Xian-Zhu Han;Ting-Ting Li;Dr. Xiangguo Guan;Dr. Wei Lu;Dr. Kun Liu;Dr. Yong Chen;Dr. Wen-Fu Fu;Dr. Chi-Ming Che

Chemistry - A European Journal 2015 Volume 21( Issue 3) pp:1184-1190

Publication Date(Web):

DOI:10.1002/chem.201405356

Abstract

Four heteroleptic copper(I) complexes containing phenanthroline and monoanionic nido-carborane-diphosphine ligands have been prepared and structurally characterized by various spectroscopic techniques and X-ray diffraction. These complexes exhibit intense absorptions in the visible range and excited-state lifetimes on the microsecond scale. Their application in visible-light-induced cross-dehydrogenative coupling reactions was investigated. Preliminary studies showed that one of the four copper(I) complexes is an efficient catalyst for photoinduced oxidative CH functionalization using oxygen as oxidant. Furthermore, α-functionalized tertiary amines were obtained in good-to-excellent yields by light irradiation (λ>420 nm) of a mixture of our Cu^I complex, tertiary amines, and a variety of nucleophiles (nitroalkane, acetone, or indoles) under aerobic conditions. Electron paramagnetic resonance measurements provided evidence for the formation of superoxide radical anions (O₂^−⋅) rather than singlet oxygen (¹O₂) during these photocatalytic reactions.

Enhanced visible light photocatalytic activity and mechanism of BiPO4 nanorods modified with AgI nanoparticles

Co-reporter:Huifang Ye, Haili Lin, Jing Cao, Shifu Chen, Yong Chen

Journal of Molecular Catalysis A: Chemical 2015 Volume 397() pp:85-92

Publication Date(Web):February 2015

DOI:10.1016/j.molcata.2014.11.005

•AgI modified BiPO4 was synthesized by deposition–precipitation method.•AgI nanoparticles dramatically enlarged the visible light absorption of BiPO4.•AgI/BiPO4 exhibited higher photocatalytic activity than AgI and BiPO4.•BiPO4 acted as an electron trap in the separation process of photocarriers.A novel visible-light-driven AgI/BiPO4 composite was synthesized by a facile room temperature deposition–precipitation method. The structures, morphologies, components and optical properties of the obtained samples were systematically characterized using X-ray powder diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, UV–vis diffuse reflectance spectroscopy and Brunauer–Emmett–Teller surface area. The loading of AgI nanoparticles endowed BiPO4 with good visible light absorption and excellent visible light photocatalytic activity for degrading rhodamine B. The kapp value of AgI/BiPO4 for degrading rhodamine B was 0.044 min−1, which was three times that of pure AgI. Besides, AgI/BiPO4 maintained good stability in the recycling process. The outstanding photocatalytic activity could be mainly attributed to the fast separation of electron–hole pairs, ensured by the enhanced photocurrent intensity, by using BiPO4 as a highly efficient electron trap.The novel AgI/BiPO4 composite synthesized by deposition–precipitation method presented excellent photocurrent intensity, photocatalytic activity as well as stability under visible light irradiation (λ > 420 nm) owing to the good visible light absorption and efficient electron–holes separation via BiPO4 electron trapping role.

Improved Photocurrents for Water Oxidation by Using MetalOrganic Framework Derived Hybrid Porous Co3O4@Carbon/BiVO4 as a Photoanode

Co-reporter:Chun-Chao Hou;Ting-Ting Li;Dr. Yong Chen;Dr. Wen-Fu Fu

ChemPlusChem 2015 Volume 80( Issue 9) pp:1465-1471

Publication Date(Web):

DOI:10.1002/cplu.201500058

Abstract

Efforts to improve the overall efficiency of photoelectrochemical water splitting by promoting interfacial charge transfer and suppressing electron–hole recombination remain a challenge. Highly porous Co₃O₄@carbon derived from metal–organic frameworks was successfully embedded on the surface of BiVO₄ nanosheets. The Co₃O₄@carbon/BiVO₄ composites were fully characterised by a variety of techniques, including powder XRD, diffuse reflectance UV/Vis spectroscopy, BET surface area calculations, SEM, TEM, energy-dispersive X-ray spectroscopy, high-angle annular dark-field scanning TEM, and X-ray photoelectron spectroscopy. The construction of a heterojunction between porous Co₃O₄ (p-Co₃O₄) and BiVO₄ significantly promoted charge transfer and suppressed the recombination of holes and electrons. Consequently, the p-Co₃O₄@carbon/BiVO₄ photoanode demonstrated approximately tenfold higher photocurrent density relative to bare BiVO₄ and bulk Co₃O₄/BiVO₄ for water oxidation under the same conditions. Also, this system displayed good durability for water oxidation and could be recycled at least three times without any loss of catalytic activity.

Platinum(II) Schiff Base Complexes as Photocatalysts for Visible-Light-Induced Cross-Dehydrogenative Coupling Reactions

Co-reporter:Dr. Deepak Prakash Shelar;Ting-Ting Li;Dr. Yong Chen;Dr. Wen-Fu Fu

ChemPlusChem 2015 Volume 80( Issue 10) pp:1541-1546

Publication Date(Web):

DOI:10.1002/cplu.201500157

Abstract

Four phosphorescent platinum(II) Schiff base complexes are screened for application in visible-light-induced cross-dehydrogenative coupling (CDC) reactions. Preliminary studies show that, among the four platinum(II) complexes, Pt3 is an efficient catalyst for CDC reactions with oxygen as an oxidant. Light irradiation (λ>420 nm) on a mixture of the Pt^II complex, tertiary amine, and a variety of nucleophiles (nitroalkanes, ketones, or indoles) under aerobic conditions gives α-functionalized tertiary amines in good to excellent yields. The photoluminescence quenching experiment reveals that the CDC reaction is initiated by photoinduced electron transfer from N-phenyltetrahydroisoquinoline to the Pt^II complex. Further, electron spin resonance (ESR) measurements clearly indicate the formation of superoxide radical anions (O₂^.−) rather than singlet oxygen (¹O₂) during the photocatalytic reaction.

Bodipy dyes bearing oligo(ethylene glycol) groups on the meso-phenyl ring: tuneable solid-state photoluminescence and highly efficient OLEDs

Co-reporter:Cui-Lian Liu, Yong Chen, Deepak P. Shelar, Cong Li, Gang Cheng and Wen-Fu Fu

Journal of Materials Chemistry A 2014 vol. 2(Issue 28) pp:5471-5478

Publication Date(Web):19 May 2014

DOI:10.1039/C4TC00720D

Borondipyrromethene (Bodipy) dyes with strong solid-state photoluminescence are highly desirable for their applications in OLEDs. In this work, a series of meso-(4-R–C6H4)-substituted Bodipy dyes (R = H for B1; R = (OCH2CH2)nOCH2CH3, n = 0–3 for B2–B5, respectively) were prepared through an acid-catalyzed reaction. The flexible ether groups attached to the periphery of B2–B5 are expected to influence the molecular arrangement and intermolecular interactions in solid state. Crystallographic analysis of B1–B4 reveals that the meso-phenyl ring is almost orthogonal to the indacene plane. Intermolecular π–π interactions are observed in B1 but absent in B2–B4. As a consequence, the dye B1 is weakly emissive in solid state, while B2–B4 emit strongly in the red region with emission quantum yields of up to 0.33. The PMMA films doped with B2 show two separated emission peaks, and their relative intensity is concentration dependent, leading to the fluorescence color varying from greenish yellow to red as the concentrations successively increased from 5 to 80 wt%. The formation of dimers in the ground state is found to be responsible for the red emission in the condensed state. Efficient OLEDs were fabricated by doping 2 wt% B2–B4 as emitters and gave high luminance, current efficiency, and external quantum efficiency of up to 920 cd m−2, 8.00 cd A−1, and 2.15%, respectively.

Highly efficient photocatalytic hydrogen evolution by nickel phosphide nanoparticles from aqueous solution

Co-reporter:Shuang Cao, Yong Chen, Chuan-Jun Wang, Ping He and Wen-Fu Fu

Chemical Communications 2014 vol. 50(Issue 72) pp:10427-10429

Publication Date(Web):24 Jul 2014

DOI:10.1039/C4CC05026F

Monodispersed nickel phosphide (Ni2P) nanoparticles were for the first time applied to photocatalytic hydrogen evolution from lactic acid aqueous solution under visible light LED irradiation using CdS nanorods as a photosensitizer. The system exhibited high photocatalytic hydrogen-generating activity and excellent stability in aqueous acidic media.

Naphthyridine–BF2 complexes with an amide-containing di-2-picolylamine receptor: Synthesis, structures and photo-induced electron transfer

Co-reporter:Yun-Ying Wu, Yong Chen, Wei-Hua Mu, Xiao-Jun Lv, Wen-Fu Fu

Journal of Photochemistry and Photobiology A: Chemistry 2013 Volume 272() pp:73-79

Publication Date(Web):15 November 2013

DOI:10.1016/j.jphotochem.2013.08.015

•Two novel naphthyridine–BF2 compounds with an amide-containing di-2-picolylamine (DPA) receptor were synthesized.•The photophysical properties were elucidated which are in line with the results of CV measurements and DFT calculations.•Fluorescence increase was realized by coordination of DPA with a second BF2 unit or metal ions.Two novel naphthyridine–BF2 compounds with an amide-containing di-2-picolylamine (DPA) receptor, namely 4 and 5, were synthesized and structurally characterized by various spectroscopic techniques and X-ray diffraction crystallography. The crystal structures of both mononuclear 4 and dinuclear 5 possessed a N,O-chelated naphthyridine–BF2 core, and the second BF2 unit in 5 was ligated to a basic amido N-atom together with a tertiary amine in the DPA part. The spectroscopic properties of 4 and 5 were investigated in various solvents and the difference between them was rationalized by the intramolecular charge transfer (ICT) and photo-induced electron transfer (PET) mechanism. Cyclic voltammetry measurements and theoretical calculations were carried out, and the results were in agreement with their spectral data.Two novel naphthyridine−BF2 compounds with an amide-containing di-2-picolylamine receptor were synthesized and structurally characterized, which displayed various fluorescent properties due to photo-induced electron transfer as evidenced by both cyclic voltammetry measures and theoretical calculations.

Large Stokes Shift Induced by Intramolcular Charge Transfer in N,O-Chelated Naphthyridine–BF2 Complexes

Co-reporter:Yun-Ying Wu, Yong Chen, Gao-Zhang Gou, Wei-Hua Mu, Xiao-Jun Lv, Mei-Ling Du, and Wen-Fu Fu

Organic Letters 2012 Volume 14(Issue 20) pp:5226-5229

Publication Date(Web):October 10, 2012

DOI:10.1021/ol302347m

Novel N,O-chelated naphthyridine–BF2 complexes with push–pull structures have been synthesized and characterized. Spectral investigations on these complexes reveal that photoinduced intramolecular charge transfer occurs and results in a large Stokes shift, which is further supported by density functional theory based theoretical calculations.

Rapid synthesis of ultralong Fe(OH)3:Cu(OH)2 core–shell nanowires self-supported on copper foam as a highly efficient 3D electrode for water oxidation

Co-reporter:Chun-Chao Hou, Chuan-Jun Wang, Qian-Qian Chen, Xiao-Jun Lv, Wen-Fu Fu and Yong Chen

Chemical Communications 2016 - vol. 52(Issue 100) pp:NaN14473-14473

Publication Date(Web):2016/12/01

DOI:10.1039/C6CC08780A

One-dimensional core–shell nanowire materials have recently received great attention as durable catalysts for water splitting. Herein we report the facile and rapid synthesis of ultralong Fe(OH)3:Cu(OH)2 core–shell nanowires grown in situ on an open 3D electrode to function as a highly efficient electrocatalyst for water oxidation. It only requires an overpotential of ∼365 mV to reach a 10 mA cm−2 current density in 1.0 M KOH. As far as we know, this shows the best result amongst Cu-based heterogeneous OER systems reported to date.

Bodipy dyes bearing oligo(ethylene glycol) groups on the meso-phenyl ring: tuneable solid-state photoluminescence and highly efficient OLEDs

Co-reporter:Cui-Lian Liu, Yong Chen, Deepak P. Shelar, Cong Li, Gang Cheng and Wen-Fu Fu

Journal of Materials Chemistry A 2014 - vol. 2(Issue 28) pp:NaN5478-5478

Publication Date(Web):2014/05/19

DOI:10.1039/C4TC00720D

Spectacular photocatalytic hydrogen evolution using metal-phosphide/CdS hybrid catalysts under sunlight irradiation

Co-reporter:Shuang Cao, Yong Chen, Chuan-Jun Wang, Xiao-Jun Lv and Wen-Fu Fu

Chemical Communications 2015 - vol. 51(Issue 41) pp:NaN8711-8711

Publication Date(Web):2015/04/16

DOI:10.1039/C5CC01799H

Enhanced photocatalytic H2-evolution by immobilizing CdS nanocrystals on ultrathin Co0.85Se/RGO–PEI nanosheets

Co-reporter:Shuang Cao, Yong Chen, Lei Kang, Zheshuai Lin and Wen-Fu Fu