Research Article www.acsami.org
Efficient Electrochemical Water Splitting Catalyzed by Electrodeposited Nickel Diselenide Nanoparticles Based Film Zonghua Pu,† Yonglan Luo,*,† Abdullah M. Asiri,‡ and Xuping Sun*,† †
Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, Sichuan, China ‡ Chemistry Department & Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia S Supporting Information *
ABSTRACT: In this contribution, we demonstrate that electrodeposited nickel diselenide nanoparticles based film on conductive Ti plate (NiSe2/Ti) is an efficient and robust electrode to catalyze both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in basic media. Electrochemical experiments show this electrode affords 10 mA cm−2 at HER overpotential of 96 mV and 20 mA cm−2 at OER overpotential of 295 mV with strong durability in 1.0 M KOH. The corresponding two-electrode alkaline water electrolyzer requires a cell voltage of only 1.66 V to achieve 10 mA cm−2 water-splitting current. This development provides us an attractive non-noble-metal catalyst toward overall water splitting applications.
KEYWORDS: electrodeposition, nickel diselenide, nanoparticles film, water splitting, hydrogen
■
INTRODUCTION With the depletion of fossil fuels and increased environmental concerns, there is an urgent need to search for CO2-free and sustainable energy sources,1,2 and hydrogen has been considered as an ideal alternative.3 Electrochemical water splitting plays a key role in the future sustainable hydrogen production and is divided into two half reactions: hydrogen evolution reaction (HER) at cathode and oxygen evolution reaction (OER) at anode. Water splitting demands a theoretical minimum voltage of 1.23 V, but commercial electrolyzers typically operate at a much higher value of 1.8−2.0 V because both reactions are thermodynamically uphill.4 To make the whole process less energy-intensive, active catalysts are used to overcome the large overpotentials.5 Precious metal-based compounds exhibit the highest catalytic activity (Pt for HER,6 Ir and Ru for OER7), but their high cost hinders widespread applications. Numerous research efforts have thus been put over the past years to make catalysts from earth-abundant transition metals for HER (phosphides,6,8−11 chalcogenides,12−14 carbides,15,16 nitrides16,17) and OER (phosphates,18,19 hydroxides,20−23 oxides,24−27 chalcogenides,28,29 nitrides30). To sustain overall water splitting with minimal overpotentials, the catalysts for HER and OER must work in the same (strongly acidic or alkaline) electrolyte.31 Using a bifunctional catalyst leads to a simplifed system and lower cost. Although proton exchange membrane technique based devices are promising for water splitting, their long-term © 2016 American Chemical Society
viability is questionable because only catalysts based on IrO2 are acid-insoluble with reasonable OER activity.32 It is therefore highly desired to design and make nonprecious metal watersplitting catalysts effcient at alkaline pH, which, however, still is a big challenge with limited success in developing such catalysts, including NiFe layered double hydroxide on nickel foam (NiFe LDH/NF),33 cobalt−cobalt oxide/N-doped carbon hybrids (CoOx@CN),34 porous cobalt phosphide/ cobalt phosphate thin film (PCPTF),35 Ni2P nanoparticles (Ni2P),36 and so forth. More recently, we developed NiSe nanowires film on NF (NiSe/NF) as an active catalyst for water electrolysis, but this work suffers from involvement of timeconsuming hydrothermal process, generation of toxic H2Se, and limited substrate choices for in situ catalyst growth.37 Herein, we report our recent effort toward this direction by growing a nickel diselenide nanoparticles film on conductive Ti plate (NiSe2/Ti) at room temperature through a straightforward and convenient electrodeposition method. When directly used as a catalytic electrode, it is efficient and robust for both HER and OER in basic electrolytes. It demands HER overpotential of 96 mV to approach 10 mA cm−2 and OER overpotential of 295 mV to deliver 20 mA cm−2 in 1.0 M KOH. The alkaline water electrolyzer based on this bifunctional electrode needs a voltage of 1.66 V to show 10 mA cm−2, Received: December 12, 2015 Accepted: January 29, 2016 Published: January 29, 2016 4718
DOI: 10.1021/acsami.5b12143 ACS Appl. Mater. Interfaces 2016, 8, 4718−4723
Research Article
ACS Applied Materials & Interfaces promising its use as a low-cost, efficient, and durable catalyst toward overall water splitting application.
■
EXPERIMENTAL SECTION
Materials. KH2PO4, K2HPO4·3H2O, NiCl2·6H2O, SeO2, and LiCl were bought from Beijing Chemical Corp., Ni(NO3)2·6H2O from Xilong Chemical Co. Ltd., and KOH from Aladdin Ltd. (Shanghai, China). Pt/C (20 wt % Pt on Vulcan XC%72R) and Nafion (5 wt %) were bought from Sigma-Aldrich. All chemicals were used as received, and the water was purified through a Millipore system. Preparation of NiSe2/Ti. NiSe2 films were grown on Ti substrates via room-temperature electrodeposition. Prior to the electrodeposition, Ti plate was washed with ethanol and water several times for removing the surface impurities. Electrodeposition was carried out using using a CHI 660D electrochemical analyzer (CH Instruments, Inc., Shanghai) in a standard three-electrode setup: Ti plate as working electrode, graphite plate as counter electrode, saturated calomel electrode (SCE) as reference electrode, and an aqueous containing 0.065 M NiCl2·6H2O, 0.035 M SeO2 and 0.2 M LiCl as electrolyte. The deposition potential is −0.45 V vs SCE. After 1 h electrodeposition, the resulting black Ti plate was submitted to careful rinsing several times with water and ethanol under ultrasonication, and then air-dried. The NiSe2 loading was determined as 2.5 mg cm−2 using a high-precision microbalance. Preparation of Ni(OH)2/Ti. Ni(OH)2/Ti was prepared as fol-lows. In brief, Ti plate serves as working electrode for room-temperature cathodic electrodeposition of nickel hydroxide under a galvanostatic mode at 1 mA cm−2 for 20 min in 0.02 M Ni(NO3)2 solution. Asobtained nanoparticles film was rinsed several times with water and airdried at room temperatures. Characterizations. X-ray powder diffraction (XRD) analysis was done on a RigakuD/MAX 2550 diffractometer with Cu Kα radiation (λ = 1.5418 Å). Scanning electron microscopy (SEM) analysis was performed on a XL30 ESEM FEG scanning electron microscope at 20 kV. Transmission electron microscopy (TEM) charaterizations were carried out on a HITACHI H-8100 electron microscope (Hita-chi, Tokyo, Japan) at 200 kV. X-ray photoelectron spectrometer (XPS) data were collected on an ESCALABMK II XPS using Mg as the exciting source. Raman data were acquired on a Renishaw 2000 model confocal microscopy Raman spectrometer with a holographic notch filter and a CCD detector (Renishaw Ltd., Gloucestershire, U.K.) at ambient conditions. SERS excitation was provided by 514.5 nm radiation from an argon ion laser with 1 μm spot. The acquisition time for one accumulation was 60 s. The Raman band of a silicon wafer at 520 cm−1 was used to calibrate the spectrometer. Electrochemical Tests. Electrochemical tests were done on a CHI 660D electrochemical analyzer in a three-electrode setup using NiSe2/ Ti, a graphite plate, and a SEC as working, counter and reference electrode, respectively. The reference electrode was calibrated to the reversible hydrogen electrode (RHE) scale in all measurements as follows: E (RHE) = E (SCE) + 1.068 V in 1.0 M KOH and E (RHE) = E (SCE) + 0.655 V in 2.0 M phosphate buffered saline (PBS). The RHE scale was calibrated using two Pt electrodes in a H2 purged electrolyte.
Figure 1. (a) XRD pattern of NiSe2 scratched down from Ti substrate. (b) Crystal structure of NiSe2 in cubic pyrite-type phase (Ni, green; Se, yellow). (c) SEM images for NiSe2/Ti. (d) TEM image of NiSe2 nanoparticles. (e) HRTEM image and (f) SAED pattern taken from NiSe2 nanoparticle.
further shows such nanoparticles are nearly spherical in shape with diameters in the range of 5 to 20 nm. The high-resolution transmission electron microscopy (HRTEM) image reveals well-resolved lattice fringes with a interplanar distance of 0.18 nm indexed to the (311) plane of NiSe2 (Figure 1e). The discrete spots in selected area electron diffraction (SAED) pattern (Figure 1f) are indexed to the (200) and (311) planes of NiSe2 phase. All these results support the formation of NiSe2 nanoparticles film after electrodeposition. As shown in Figure 2a, the XPS survey spectrum of NiSe2/Ti presents the peaks of Ni and Se with signals of C and O elements due to contamination/surface oxidation of the product.38 Figure 2b-2d show the XPS spectra in the Ni 2p, Se 3d, and O 1s regions, respectively. The Ni 2p3/2 and Ni 2p1/2 peaks appear at 855.7 and 873.4 eV, respectively, corresponding to Ni (II) (Figure 2b). In Figure 2c, the Se 3d peak at 54.3 eV implies the presence of Se22− in the deposit and the broad peak at 58.9 eV arises from surface oxidation of Se species.39 The O 1s spectrum (Figure 2d) shows the existence of oxidized Ni species.40 The HER activity of NiSe2/Ti (NiSe2 loading: 2.5 mg cm−2) was evaluated at a scan rate of 5 mV s−1 in 1.0 M KOH. Fe impurity in KOH was removed using reported method.41−43 For comparison, commercial Pt/C (20 wt % Pt/XC-72) deposited on Ti plate with the same loading and bare Ti plate were also tested. Figure 3a shows the corresponding polarization curves. iR compensation based on resistance test was
■
RESULTS AND DISCUSSION The photograph reveals a color change for Ti plate from gray white into black after electrodeposition (Figure S1). The XRD pattern of the deposit presents diffraction peaks well-indexed to the (200), (210), (211), (311), (023), and (321) planes of cubic pyrite-type NiSe2 phase (JCPDS No. 65-1843), with Ni atoms octahedrally bonded to adjacent Se atoms and cornershared octahedra (Figure 1b). The SEM analysis (Figure 1c) shows the full coverage of Ti plate (Figure S2) with NiSe2 nanoparticles film about 1.5 μm in thickness (Figure S3). EDX spectrum indicates a 1:2 atmoic ratio of Ni:Se for the NiSe2 nanoparticles film (Figure S4). The TEM image (Figure 1d) 4719
DOI: 10.1021/acsami.5b12143 ACS Appl. Mater. Interfaces 2016, 8, 4718−4723
Research Article
ACS Applied Materials & Interfaces
for NiSe2/Ti electrode. XPS analysis (Figure S6) for post-HER NiSe2/Ti suggests the presence of Ni(II) and the increased peak intensity of SeOx can be attributed to oxidation of Se at NiSe2 surface in strongly basic medium, which is consistent with our recent NiSe catalyst.37 Further XRD analysis concludes the nanoparticles show unchanged pattern after HER electrolysis (Figure S7). Our NiSe2/Ti electrode also performs well in 2.0 M PBS (pH = 7) with the need of overpotential of 143 mV to drive 2 mA cm−2 (Figure S8). This overpotential is lower than those for other Pt-free HER catalyst in neutral media, including Co-NRCNTs (380 mV),46 H2− CoCat/FTO (385 mV),47 CuMoS4 (210 mV),48 and MoS2/Mo (171 mV).49 To examine the durability of NiSe2/Ti, it was submitted to continuous cyclic voltammetry (CV) scanning between −0.28 and +0.07 V with a scan rate of 100 mV s−1. Only negligible difference is observed for the polarization curves obtained before and after 1000 CV cycles (Figure 3c). Its long-term stability was also tested by electrolysis at a fixed overpotential of 121 mV and the current density remains at 20 mA cm−2 with slightly degradation over 36-h electrolysis (Figure 3d). After electrolysis experiment, the film still maintains its morphological integrity on Ti plate (Figure S9) and ICP-MS analysis reveals the amount of NiSe2 as 2.47 mg cm−2 with a Ni:Se ratio of 1:1.92. These results imply excellent long-term stability of the NiSe2/Ti as a HER electrode in 1.0 M KOH. We next assessed the OER activity of NiSe2/Ti in the same electrolyte. Figure 4a shows the polarization curves for NiSe2/
Figure 2. (a) XPS survey spectrum for NiSe2/Ti. XPS spectra in the (b) Ni 2p, (c) Se 3d, and (d) O 1s regions.
Figure 3. (a) Polarization curves of NiSe2/Ti, Pt/C on Ti plate, and bare Ti plate with a scan rate of 5 mV s−1. (b) Tafel plots of NiSe2/Ti and Pt/C on Ti plate. (c) Polarization curves recorded for NiSe2/Ti before and after 1000 CV cycles at a scan rate of 5 mV s−1. (d) Timedependent current density curve for NiSe2/Ti under static overpotential of 115 mV for 36 h. The electrolyte is 1.0 M KOH.
applied for all polarization curves.44 As observed, Pt/C on Ti plate has excellent activity while bare Ti is not active for the HER. The NiSe2/Ti electrode is efficient for HER with onset overpotential as low as 20 mV and subsequent scanning toward negative potentials leads to sharply rised current density and vigorous evolution of H2 bubbles from electrode surface. This electrode shows 10 mA cm−2 at overpotential of only 70 mV, which is lower than the values for other bifunctional catalysts (210 mV for NiFe LDH/NF,33 232 mV for CoOx@C,34 ∼ 380 mV for PCPTF,35 and ∼300 mV for Ni2P36) in 1.0 M KOH, demonstrating its superior HER activity. Table S1 compares the HER performance of NiSe2/Ti with other non-noble metal HER catalysts. Figure 3b shows the Tafel plots. NiSe2/Ti and Pt/C have Tafel slopes of 82 and 61 mV dec−1, respectively. The roughness factor of the catalytic film was estimated by comparing the double layer capacitances at the solid−liquid interface of bare Ti plate and NiSe2/Ti (Figure S5).45 The capacitances of bare Ti plate and NiSe2/Ti are 2.4 and 27 mF cm−2, respectively, implying a roughness factor of about 11.2
Figure 4. (a) Polarization curves of NiSe2/Ti, RuO2 on Ti plate, and bare Ti plate with a scan rate of 2 mV s−1. (b) Tafel plots of NiSe2/Ti and RuO2 on Ti plate. (c) Polarization curves at a scan rate of 2 mV s−1 recorded for NiSe2/Ti before and after 1000 CV cycles between +1.1 and +1.7 V. (d) Time-dependent current−density curve for NiSe2/Ti under static overpotential of 153 mV for 36 h. The electrolyte is 1.0 M KOH.
Ti, RuO2 on Ti plate with the same catalyst loading, and bare Ti plate. RuO2 on Ti plate is highly active for water oxidation with low onset potential of approximately 1.5 V vs RHE with the need of overpotential of 290 mV to achieve 10 mA cm−2. Bare Ti plate exhibits poor OER activity, but NiSe2/Ti electrode is highly efficient for the OER with the need of overpotential of 295 mV to reach 20 mA cm−2. The oxidation peak at 1.4 V can be ascribed to Ni(II) to Ni(III).50 Although this overpotential is higher than that for NiFe LDH/NF (269 4720
DOI: 10.1021/acsami.5b12143 ACS Appl. Mater. Interfaces 2016, 8, 4718−4723
Research Article
ACS Applied Materials & Interfaces mV)33 and NiSe/NF (270 mV),37 it is still lower than those for some other bifunctional catalysts (320 mV for CoOx@CN,34 ∼310 mV for PCPTF35). Table S2 presents a more detailed comparison of OER performance for NiSe2/Ti with other nonprecious metal OER electrocatalysts. Figure 4b shows the Tafel plots for NiSe2/Ti and RuO2 on Ti plate, and the Tafel slope for NiSe2/Ti (82 mV dec−1) is lower than that for RuO2 on Ti plate (87 mV dec−1). Also note that our OER electrode has excellent long-term electrochemical durability in 1.0 M KOH (Figure 4c and d). OER electrolysis leads to larger aggregated structures with partially exposed Ti substrate (Figure S10) and ICP-MS analysis concludes that the amount of NiSe2 is 2.39 mg cm−2 with Ni:Se atomic ratio of 1:1.87. XPS analysis for post-OER NiSe2/Ti indicates the formation of Ni(III) with decreased peak intensity of Se 3d, as shown in Figure S11. Raman spectra analysis and TEM images (Figure S12) further confirm the formation of amorphous Ni oxo/ hydroxide51,52 after OER electrolysis. Like post-HER nanoparticles, these post-OER ones also shows unchanged XRD pattern (Figure S13). Thus, it is rational to say that Ni oxo/ hydroxide species formed at the surface catalyzes OER in our present study.36,37 We also tested the OER activity of NiSe2/Ti in PBS. As shown in Figure S14, this electrode is also active for OER in neutral media with the need of overpotential of 770 mV to afford 10 mA cm−2. Although early studies have shown that nickel oxide and hydroxide are active OER catalysts in basic media,33,53−57 we found that electrodeposited Ni(OH)2 nanoparticles film on Ti plate58 with similar catalyst loading exhibits much inferior OER activity over NiSe2/Ti in the same electrolyte (Figure S15). The superior OER activity for NiSe2/ Ti could be explained as following: (1) NiSe2/Ti has a roughness factor nearly 3.0 times of that for Ni(OH)2/Ti (Figure S5) and hence exposes more active sites to catalyze OER; (2) the NiSe2 nanoparticles film also plays as a significant role as conducting support13,59 in providing an effective electron path to the NiOOH active species at the surface during OER. The conductive network of NiSe2 nanoparticles could contribute the superior catalytic acitivty. Pt and RuO2 are among the most efficient electrocatalyst for H2 and O2 generation, respectively, but the oxidation of Pt or reduction of RuO2 causes detrimental catalyst deactivation and thus they both cannot perform any bifunctional activity. Based on above results, the NiSe2/Ti was tested as a bifunctional catalyst for full water splitting. An electrolyzer was made in a two-electrode configuration using NiSe2/Ti as anode and cathode for electrolysis in 1.0 M KOH at 25 °C. This NiSe2/ Ti||NiSe2/Ti system offers 10 mA cm−2 at a cell voltage of only 1.66 V (Figure 5a). Movie S1 illustrates vigorous gas evolution on both electrodes at 1.60 V. The use of Pt/C on Ti plate as both electrodes (Pt/C||Pt/C) delivers much diminished watersplitting current while the benchmarking electrolyzer using RuO2 on Ti plate as anode and Pt/C on Ti plate as cathode (RuO2||Pt/C) needs 1.53 V to attain 10 mA cm−2. The cell voltage for NiSe2/Ti||NiSe2/Ti is lower than that for NiFe LDH/NF (1.70 V)33 based electrolysis systems at the same current density. The Tafel slope for NiSe2/Ti||NiSe2/Ti (172 mV dec−1) is lower than that for Pt/C||Pt/C (178 mV dec−1) and higher than that for RuO2||Pt/C (167 mV dec−1), as shown in Figure 5b. Remarkably, this NiSe2/Ti||NiSe2/Ti system maintains high stability during electrolysis (Figure 5c). The generated H2 and O2 was quantitatively mreasured using a calibrated pressure sensor monitoring the pressure change both compartments of a H-type electrolytic cell.6 To determine the
Figure 5. (a) Polarization curves of NiSe2/Ti||NiSe2/Ti, Pt/C||Pt/C, and RuO2||Pt/C for overall water splitting with a scan rate of 2 mV s−1. (b) Corresponding Tafel plots. (c) Chronopotentiometric curve of NiSe2/Ti water-splitting system at 20 mA cm−2. (d) Amount of gas theoretically calculated and experimentally measured versus time for NiSe2/Ti||NiSe2/Ti.
Faradaic efficiency (FE), we compared the amount of experimentally quantified gas with theoretically calculated gas using the chronopotentiometric reaction, and the agreement of both values reveals that both reactions have 100% FE with nearly 2:1 ratio of H2 to O2 (Figure 5d). After overall water splitting, the film on cathode still maintains its full coverage on the Ti plate and ICP-MS analysis reveals the amount of NiSe2 as 2.42 mg cm−2 with a Ni:Se ratio of 1:1.92. Larger aggregated structures appear on anode (Figure S16) and ICP-MS analysis shows the amount of NiSe2 as 2.35 mg cm−2 with a Ni:Se ratio of 1:1.86. Note that Co-doping of such NiSe2 leads to enhanced electrocatalytic activities.60
■
CONCLUSION In summary, electrodeposited NiSe2 nanoparticles based film functions as an active and robust bifunctional catalyst for both HER and OER in strongly basic media. The resulting NiSe2/Ti needs overpotential of 96 mV to drive 10 mA cm−2 for HER and 295 mV to afford 20 mA cm−2 for OER. The two-electrode alkaline water electrolyzer attains 10 mA cm−2 at 1.66 V with excellent stability. Unlike previous NiSe/NF catalytic electrode, a wealth of transition metal chalcogenides film can be, in principle, easily electrodeposited on any conductive substrates. The superior catalytic activity and stability, along with the easy and scalable fabrication process, of this electrode promise its use as a cheap catalyst material toward water electrolysis application. This work also provides us a starting point to explore the utilization of electrodeposited transition metal chalcogenides film as an attractive water-splitting electrode in technological devices for mass production of hydrogen fuel.
■
ASSOCIATED CONTENT
S Supporting Information *
The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acsami.5b12143. Optical photograph; SEM images; EDX, XPS, and Raman spectra; Tables S1 and S2; CVs; XRD pattern; polarization curves (PDF) 4721
DOI: 10.1021/acsami.5b12143 ACS Appl. Mater. Interfaces 2016, 8, 4718−4723
Research Article
ACS Applied Materials & Interfaces
■
(17) Cao, B.; Veith, G. M.; Neuefeind, J. C.; Adzic, R. R.; Khalifah, P. G. Mixed Close-Packed Cobalt Molybdenum Nitrides as Non-noble Metal Electrocatalysts for the Hydrogen Evolution Reaction. J. Am. Chem. Soc. 2013, 135, 19186−19192. (18) Kanan, M. W.; Nocera, D. G. In situ Formation of an OxygenEvolving Catalyst in Neutral Water Containing Phosphate and Co2+. Science 2008, 321, 1072−1075. (19) Lee, S. W.; Carlton, C.; Risch, M.; Surendranath, Y.; Chen, S.; Furutsuki, S.; Yamada, A.; Nocera, D. G.; Shao-Horn, Y. The Nature of Lithium Battery Materials under Oxygen Evolution Reaction Conditions. J. Am. Chem. Soc. 2012, 134, 16959−16962. (20) Hutchings, G. S.; Zhang, Y.; Li, J.; Yonemoto, B. T.; Zhou, X.; Zhu, K.; Jiao, F. In Situ Formation of Cobalt Oxide Nanocubanes as Efficient Oxygen Evolution Catalysts. J. Am. Chem. Soc. 2015, 137, 4223−4229. (21) Song, F.; Hu, X. Ultrathin Cobalt-Manganese Layered Double Hydroxide Is an Efficient Oxygen Evolution Catalyst. J. Am. Chem. Soc. 2014, 136, 16481−16484. (22) Long, X.; Li, J.; Xiao, S.; Yan, K.; Wang, Z.; Chen, H.; Yang, S. A Strongly Coupled Graphene and FeNi Double Hydroxide Hybrid as an Excellent Electrocatalyst for the Oxygen Evolution Reaction. Angew. Chem., Int. Ed. 2014, 53, 7584−7588. (23) Lu, X.; Zhao, C. Electrodeposition of Hierarchically Structured Three-Dimensional Nickel-Iron Electrodes for Efficient Oxygen Evolution at High Current Densities. Nat. Commun. 2015, 6, 6616. (24) Smith, R. D. L.; Prévot, M. S.; Fagan, R. D.; Zhang, Z.; Sedach, P. A.; Siu, M. K.; Trudel, S.; Berlinguette, C. P. Photochemical Route for Accessing Amorphous Metal Oxide Materials for Water Oxidation Catalysis. Science 2013, 340, 60−63. (25) Meng, Y.; Song, W.; Huang, H.; Ren, Z.; Chen, S.; Suib, S. L. Structure-Property Relationship of Bifunctional MnO2 Nanostructures: Highly Efficient, Ultra-Stable Electrochemical Water Oxidation and Oxygen Reduction Reaction Catalysts Identified in Alkaline Media. J. Am. Chem. Soc. 2014, 136, 11452−11464. (26) Jung, J. I.; Jeong, H. Y.; Lee, J. S.; Kim, M. G.; Cho, J. A Bifunctional Perovskite Catalyst for Oxygen Reduction and Evolution. Angew. Chem., Int. Ed. 2014, 53, 4582−4586. (27) Ma, T.; Dai, S.; Jaroniec, M.; Qiao, S. Metal-Organic Framework Derived Hybrid Co3O4-Carbon Porous Nanowire Arrays as Reversible Oxygen Evolution Electrodes. J. Am. Chem. Soc. 2014, 136, 13925− 13931. (28) Zhou, W.; Wu, X.; Cao, X.; Huang, X.; Tan, C.; Tian, J.; Liu, H.; Wang, J.; Zhang, H. Ni3S2 Nanorods/Ni Foam Composite Electrode with Low Overpotential for Electrocatalytic Oxygen Evolution. Energy Environ. Sci. 2013, 6, 2921−2924. (29) Liu, Y.; Cheng, H.; Lyu, M.; Fan, S.; Liu, Q.; Zhang, W.; Zhi, Y.; Wang, C.; Xiao, C.; Wei, S.; Ye, B.; Xie, Y. Low Overpotential in Vacancy-Rich Ultrathin CoSe2 Nanosheets for Water Oxidation. J. Am. Chem. Soc. 2014, 136, 15670−15675. (30) Xu, K.; Chen, P.; Li, X.; Tong, Y.; Ding, H.; Wu, X.; Chu, W.; Peng, Z.; Wu, C.; Xie, Y. Metallic Nickel Nitride Nanosheets Realizing Enhanced Electrochemical Water Oxidation. J. Am. Chem. Soc. 2015, 137, 4119−4125. (31) Hernández-Pagán, E. A.; Vargas-Barbosa, N. M.; Wang, T.; Zhao, Y.; Smotkin, E. S.; Mallouk, T. E. Resistance and Polarization Losses in Aqueous Buffer-Membrane Electrolytes for Water-Splitting Photoelectrochemical Cells. Energy Environ. Sci. 2012, 5, 7582−7589. (32) Danilovic, N.; Subbaraman, R.; Chang, K.; Chang, S. H.; Kang, Y. J.; Snyder, J.; Paulikas, A. P.; Strmcnik, D.; Kim, Y.; Myers, D.; Stamenkovic, V. R.; Markovic, N. M. J. Phys. Chem. Lett. 2014, 5, 2474−2478. (33) Luo, J.; Im, J.-H.; Mayer, M. T.; Schreier, M.; Nazeeruddin, M. K.; Park, N. G.; Tilley, S. D.; Fan, H.; Grätzel, M. Water Photolysis at 12.3% Efficiency via Perovskite Photovoltaics and Earth-Abundant Catalysts. Science 2014, 345, 1593−1596. (34) Jin, H.; Wang, J.; Su, D.; Wei, Z.; Pang, Z.; Wang, Y. In situ Cobalt-Cobalt Oxide/N-Doped Carbon Hybrids As Superior Bifunctional Electrocatalysts for Hydrogen and Oxygen Evolution. J. Am. Chem. Soc. 2015, 137, 2688−2694.
H2 and O2 evolution on NiSe2/Ti electrodes in a twoelectrode setup driven by a DC power supply with a cell voltage of 1.60 V in 1.0 M KOH (AVI)
AUTHOR INFORMATION
Corresponding Authors
*E-mail:
[email protected]. *E-mail:
[email protected]. Notes
The authors declare no competing financial interest.
■
REFERENCES
(1) Bard, A. J.; Fox, M. A. Artificial Photosynthesis: Solar Splitting of Water to Hydrogen and Oxygen. Acc. Chem. Res. 1995, 28, 141−145. (2) Chow, J.; Kopp, R. J.; Portney, P. R. Energy Resources and Global Development. Science 2003, 302, 1528−1531. (3) Nocera, D. G. The Artificial Leaf. Acc. Chem. Res. 2012, 45, 767− 776. (4) Zeng, K.; Zhang, D. Recent Progress in Alkaline Water Electrolysis for Hydrogen Production and Applications. Prog. Energy Combust. Sci. 2010, 36, 307−326. (5) Walter, M. G.; Warren, E. L.; McKone, J. R.; Boettcher, S. W.; Mi, Q.; Santori, E. A.; Lewis, N. S. Solar Water Splitting Cell. Chem. Rev. 2010, 110, 6446−6473. (6) Tian, J.; Liu, Q.; Asiri, A. M.; Sun, X. Self-Supported Nanoporous Cobalt Phosphide Nanowire Arrays: An Efficient 3D HydrogenEvolving Cathode over the Wide Range of pH 0−14. J. Am. Chem. Soc. 2014, 136, 7587−7590. (7) Lee, Y.; Suntivich, J.; May, K. J.; Perry, E. E.; Shao-Horn, Y. Synthesis and Activities of Rutile IrO2 and RuO2 Nanoparticles for Oxygen Evolution in Acid and Alkaline Solutions. J. Phys. Chem. Lett. 2012, 3, 399−404. (8) Popczun, E. J.; McKone, J. R.; Read, C. G.; Biacchi, A. J.; Wiltrout, A. M.; Lewis, N. S.; Schaak, R. E. Nanostructured Nickel Phosphide as an Electrocatalyst for the Hydrogen Evolution Reaction. J. Am. Chem. Soc. 2013, 135, 9267−9270. (9) Popczun, E. J.; Read, C. G.; Roske, C. W.; Lewis, N. S.; Schaak, R. E. Highly Active Electrocatalysis of the Hydrogen Evolution Reaction by Cobalt Phosphide Nanoparticles. Angew. Chem. 2014, 126, 5531− 5534. (10) Liu, Q.; Tian, J.; Cui, W.; Cheng, N.; Asiri, A. M.; Sun, X. Carbon Nanotubes Decorated with CoP Nanocrystals: A Highly Active Non-Noble-Metal Nanohybrid Electrocatalyst for Hydrogen Evolution. Angew. Chem., Int. Ed. 2014, 53, 6710−6714. (11) Jiang, P.; Liu, Q.; Liang, Y.; Tian, J.; Asiri, A. M.; Sun, X. A CostEffective 3D Hydrogen Evolution Cathode with High Catalytic Activity: FeP Nanowire Array as the Active Phase. Angew. Chem., Int. Ed. 2014, 53, 12855−12859. (12) Xu, Y.; Gao, M.; Zheng, Y.; Jiang, J.; Yu, S. Nickel/Nickel(II) Oxide Nanoparticles Anchored onto Cobalt(IV) Diselenide Nanobelts for the Electrochemical Production of Hydrogen. Angew. Chem., Int. Ed. 2013, 52, 8546−8550. (13) Kong, D.; Wang, H.; Lu, Z.; Cui, Y. CoSe2 Nanoparticles Grown on Carbon Fiber Paper: An Efficient and Stable Electrocatalyst for Hydrogen Evolution Reaction. J. Am. Chem. Soc. 2014, 136, 4897− 4900. (14) Morales-Guio, C. G.; Hu, X. Amorphous Molybdenum Sulfides as Hydrogen Evolution Catalysts. Acc. Chem. Res. 2014, 47, 2671− 2681. (15) Cui, W.; Cheng, N.; Liu, Q.; Ge, C.; Asiri, A. M.; Sun, X. Mo2C Nanoparticles Decorated Graphitic Carbon Sheets: BiopolymerDerived Solid-State Synthesis and Application as an Efficient Electrocatalyst for Hydrogen Generation. ACS Catal. 2014, 4, 2658−2661. (16) Chen, W.; Muckerman, J. T.; Fujita, E. Recent Developments in Transition Metal Carbides and Nitrides as Hydrogen Evolution Electrocatalysts. Chem. Commun. 2013, 49, 8896−8909. 4722
DOI: 10.1021/acsami.5b12143 ACS Appl. Mater. Interfaces 2016, 8, 4718−4723
Research Article
ACS Applied Materials & Interfaces (35) Yang, Y.; Fei, H.; Ruan, G.; Tour, J. M. Porous Cobalt-Based Thin Film as a Bifunctional Catalyst for Hydrogen Generation and Oxygen Generation. Adv. Mater. 2015, 27, 3175−3180. (36) Stern, L. A.; Feng, L.; Song, F.; Hu, X. Ni2P as a Janus Catalyst for Water Splitting: the Oxygen Evolution Activity of Ni2P Nanoparticles. Energy Environ. Sci. 2015, 8, 2347−2351. (37) Tang, C.; Cheng, N.; Pu, Z.; Xing, W.; Sun, X. NiSe Nanowire Film Supported on Nickel Foam: An Efficient and Stable 3D Bifunctional Electrode for Full Water Splitting. Angew. Chem., Int. Ed. 2015, 54, 9351−9355. (38) Panneerselvam, A.; Malik, M. A.; Afzaal, M.; O’Brien, P.; Helliwell, M. The Chemical Vapor Deposition of Nickel Phosphide or Selenide Thin Films from a Single Precursor. J. Am. Chem. Soc. 2008, 130, 2420−2421. (39) Huang, S.; He, Q.; Chen, W.; Qiao, Q.; Zai, J.; Qian, X. Ultrathin FeSe2 Nanosheets: Controlled Synthesis and Application as a Heterogeneous Catalyst in Dye-Sensitized Solar Cells. Chem. - Eur. J. 2015, 21, 4085−4091. (40) Biesinger, M. C.; Payne, B. P.; Lau, L. W.; Gerson, A.; Smart, R. X-ray Photoelectron Spectroscopic Chemical State Quantification of Mixed Nickel Metal, Oxide and Hydroxide Systems. Surf. Interface Anal. 2009, 41, 324−332. (41) Trotochaud, L.; Young, S. L.; Ranney, J. K.; Boettcher, S. W. Nickel-Iron Oxyhydroxide Oxygen-Evolution Electrocatalysts: The Role of Intentional and Incidental Iron Incorporation. J. Am. Chem. Soc. 2014, 136, 6744−6753. (42) Smith, A. M.; Trotochaud, L.; Burke, M. S.; Boettcher, S. W. Contributions to Activity Enhancement via Fe Incorporation in Ni(oxy)hydroxide/borate Catalysts for Near-Neutral pH Oxygen Evolution. Chem. Commun. 2015, 51, 5261−5263. (43) Burke, M. S.; Zou, S.; Enman, L. J.; Kellon, J. E.; Gabor, C. A.; Pledger, E.; Boettcher, S. W. Revised Oxygen Evolution Reaction Activity Trends for First-Row Transition-Metal (Oxy)hydroxides in Alkaline Media. J. Phys. Chem. Lett. 2015, 6, 3737−3742. (44) Xing, Z.; Liu, Q.; Asiri, A. M.; Sun, X. Closely Interconnected Network of Molybdenum Phosphide Nanoparticles: A Highly Efficient Electrocatalyst for Generating Hydrogen from Water. Adv. Mater. 2014, 26, 5702−5707. (45) Tian, J.; Liu, Q.; Cheng, N.; Asiri, A. M.; Sun, X. Self-Supported Cu3P Nanowire Arrays as an Integrated High-Performance ThreeDimensional Cathode for Generating Hydrogen from Water. Angew. Chem., Int. Ed. 2014, 53, 9577−9581. (46) Zou, X.; Huang, X.; Goswami, A.; Silva, R.; Sathe, B. R.; Mikmekova, E.; Asefa, T. Cobalt-Embedded Nitrogen-Rich Carbon Nanotubes Efficiently Catalyze Hydrogen Evolution Reaction at All pH Values. Angew. Chem., Int. Ed. 2014, 53, 4372−4376. (47) Cobo, S.; Heidkamp, J.; Jacques, P.-A.; Fize, J.; Fourmond, V.; Guetaz, L.; Jousselme, B.; Ivanova, V.; Dau, H.; Palacin, S.; Fontecave, M.; Artero, V. A Janus Cobalt-Based Catalytic Material for ElectroSplitting of Water. Nat. Mater. 2012, 11, 802−807. (48) Tran, P.; Nguyen, M.; Pramana, S.; Bhattacharjee, A.; Chiam, S.; Fize, J.; Field, M.; Artero, V.; Wong, L.; Loo, J.; Barber, J. Copper Molybdenum Sulfide: a New Efficient Electrocatalyst for Hydrogen Production from Water. Energy Environ. Sci. 2012, 5, 8912−8916. (49) Pu, Z.; Liu, Q.; Asiri, A. M.; Luo, Y.; Sun, X.; He, Y. 3D Macroporous MoS2 Thin Film: in Situ Hydrothermal Preparation and Application as a Highly Active Hydrogen Evolution Electrocatalyst at All pH Values. Electrochim. Acta 2015, 168, 133−138. (50) Louie, M. W.; Bell, A.T. An Investigation of Thin-Film Ni−Fe Oxide Catalysts for the Electrochemical Evolution of Oxygen. J. Am. Chem. Soc. 2013, 135, 12329−12337. (51) Joya, K. S.; Sala, X. In Situ Raman and Surface-Enhanced Raman Spectroscopy on Working Electrodes: Spectroelectrochemical Characterization of Water Oxidation Electrocatalysts. Phys. Chem. Chem. Phys. 2015, 17, 21094−21103. (52) Chang, J.; Xiao, Y.; Xiao, M.; Ge, J.; Liu, C.; Xing, W. Surface Oxidized Cobalt-Phosphide Nanorods As an Advanced Oxygen Evolution Catalyst in Alkaline Solution. ACS Catal. 2015, 5, 6874− 6878.
(53) Wang, J.; Zhong, H.; Qin, Y.; Zhang, X. An Efficient ThreeDimensional Oxygen Evolution Electrode. Angew. Chem., Int. Ed. 2013, 52, 5248−5253. (54) Qiu, Y.; Xin, L.; Li, W. Electrocatalytic Oxygen Evolution over Supported Small Amorphous Ni−Fe Nanoparticles in Alkaline Electrolyte. Langmuir 2014, 30, 7893−7901. (55) Wang, L.; Lin, C.; Huang, D.; Zhang, F.; Wang, M.; Jin, J. A Comparative Study of Composition and Morphology Effect of NixCo1−x(OH)2 on Oxygen Evolution/Reduction Reaction. ACS Appl. Mater. Interfaces 2014, 6, 10172−10180. (56) Gao, M.; Sheng, W.; Zhuang, Z.; Fang, Q.; Gu, S.; Jiang, J.; Yan, Y. Efficient Water Oxidation Using Nanostructured α-NickelHydroxide as an Electrocatalyst. J. Am. Chem. Soc. 2014, 136, 7077− 7084. (57) Kuai, L.; Geng, J.; Chen, C.; Kan, E.; Liu, Y.; Wang, Q.; Geng, B. A Reliable Aerosol-Spray-Assisted Approach to Produce and Optimize Amorphous Metal Oxide Catalysts for Electrochemical Water Splitting. Angew. Chem., Int. Ed. 2014, 53, 7547−7551. (58) Pu, Z.; Liu, Q.; Tang, C.; Asiri, A. M.; Sun, X. Ni2P Nanoparticle Films Supported on a Ti Plate as an Efficient Hydrogen Evolution Cathode. Nanoscale 2014, 6, 11031−11034. (59) Gong, F.; Wang, H.; Xu, X.; Zhou, G.; Wang, Z. In Situ Growth of Co0.85Se and Ni0.85Se on Conductive Substrates as HighPerformance Counter Electrodes for Dye-Sensitized Solar Cells. J. Am. Chem. Soc. 2012, 134, 10953−10958. (60) Liu, T.; Asiri, A. M.; Sun, X. Electrodeposited Co-Doped NiSe2 Nanoparticles Film: A Good Electrocatalyst for Efficient Water Splitting. Nanoscale 2016, DOI: 10.1039/C5NR07170D.
4723
DOI: 10.1021/acsami.5b12143 ACS Appl. Mater. Interfaces 2016, 8, 4718−4723
