Enhanced CO2 Electrolysis with Mn-doped SrFeO3-δ Cathode
- Corresponding author: Li-Zhen GAN, lzgan@fafu.edu.cn
Citation:
Shi-Sheng HOU, Ze-Tong XU, You-Kai ZHANG, Kui XIE, Li-Zhen GAN. Enhanced CO2 Electrolysis with Mn-doped SrFeO3-δ Cathode[J]. Chinese Journal of Structural Chemistry,
;2020, 39(9): 1662-1668.
doi:
10.14102/j.cnki.0254-5861.2011-2672
Solid oxide electrolysers have demonstrated tremendous benefits of using renewable electricity to efficiently convert CO2 into fuel[1-3]. The high operation temperature delivers enhanced dynamic and thermodynamic advantages. By applying an external potential, CO2 can be directly electrolyzed into CO and O2 in an oxygen-ion-conducting solid oxide electrolyser[4-7].
Traditional Ni-YSZ composite electrode has been widely used for CO2 electrolysis; however, the inherent oxidation-reduction instability of Ni–YSZ limits its application when performing direct CO2 electrolysis without reducing gas atmosphere[8-12]. It is reported that CO2 electrolysis using perovskite ceramics electrodes would be highly promising[13]. Perovskite oxide electrode materials have been therefore extensively studied[14, 15], which is due to that perovskite oxides are very good parent materials for tailoring chemical composition through the control of element doping in A and B sites. And some of them have shown long-term stability, carbon deposition resistance, sulfur poisoning resistance and excellent transport properties.
The ABO3-type perovskite oxide could provide layered lattice structure that has huge potential for the cation doping strategy for the development of new electrode materials[16]. Perovskite SrFeO3-δ oxide has been intensively studied as the cathode of solid oxide fuel cells and they have shown good electrochemical performance[17-19]. SrFeO3-δ oxide is a typical conductor while it still demonstrates high conductivity in reducing atmosphere[20]. As a cathode, it has been proven to be effective for steam electrolysis in a solid oxide electrolyser. Enhancing the concentration of oxygen vacancy with dopant would be highly favourable to improve electrode activity. In this case, oxygen defects would not only improve the transport properties but also facilitate the chemisorption of CO2 on oxide surfaces at high temperature.
In this work, we dope Mn into the B-site of SrFeO3-δ lattice to increase oxygen vacancy concentration towards CO2 electrolysis. The electrical properties and surface oxygen exchange coefficient of the materials are investigated. We perform CO2 electrolysis with Mn-doped cathode.
SrFeO3-δ and SrFe0.85Mn0.15O3-δ are synthesized by a solid state reaction method with heat treatment at 1300 ℃[21, 22]. Reduced samples are prepared by treating the samples in 5%H2/Ar at 800~1000 ℃ for 3~5 hours. La0.9Sr0.1Ga0.8-Mg0.2O3-δ (LSGM) electrolyte powders are prepared using a solid state reaction method with heat treatment at 1000 ℃. (La0.8Sr0.2)0.95MnO3-δ (LSM) and Ce0.8Sm0.2O2-δ (SDC) powders are synthesized using a glycine-nitrate combustion method[23, 24]. The phase formation of powder samples is analyzed using X-ray diffraction (D/MAX2500V). About 2.0 g of SrFeO3-δ or SrFe0.85Mn0.15O3-δ powder is pressed into a bar and sintered at 1300 ℃ for 6 h in air for conductivity test using a DC four-terminal method (Keithley 2000)[25]. Electrical conductivity relaxation (ECR) method is used to test the surface oxygen exchange coefficient with oxygen partial pressure shifting between 10-18 and 10-12 atm at 800 ℃[26, 27]. In our work, we use the atmospheres of CO/CO2 by changing the ratio between CO and CO2 to get the two different oxygen partial pressures.
LSGM electrolyte is prepared by pressing the powder sample and sintered at 1500 ℃ for 10 hours in air. SrFeO3-δ/SDC and SrFe0.85Mn0.15O3-δ/SDC slurries are prepared by milling the SrFeO3-δ or SrFe0.85Mn0.15O3-δ with SDC at a weight ratio of 65:35 in alpha-terpineol with suitable cellulose additive. Single cells are assembled using screen printing method and then heat-treated at 1100 ℃. The microstructures of single cells are observed using a scanning electron microscope (SEM, JEOL Ltd). Electrochemical measurement of CO2 electrolysis is recorded using an electrochemical station (IM6, Zahner, Germany). Pure CO2 (50 mL·min-1) is fed to cathode while the anode is exposed to air. The generation of CO is analyzed using an online gas chromatograph (GC2014, Shimazu).
Fig. 1a and 1b present the XRD patterns of the powder samples in oxidized and reduced states, respectively. The SrFeO3-δ is in a tetragonal phase while the Mn-doped SrFe0.85Mn0.15O3-δ in a cubic phase. After reduction, a phase transition to orthorhombic phase is observed both for SrFeO3-δ and SrFe0.85Mn0.15O3-δ[28]. We therefore obtain Sr2Fe2O5 phase which is the active phase for CO2 electrolysis at high temperature. The doping of Mn changes the cell parameters as confirmed by the shift of diffraction peaks. As shown in Table 1, we use iodometric method[24, 29] to analyze the oxygen nonstoichiometry of SrFeO3-δ and SrFe0.85Mn0.15O3-δ in oxidized and reduced states, respectively. The oxygen deficiency is 0.2880 for SrFeO3-δ while it is enhanced to 0.3386 for SrFe0.85Mn0.15O3-δ through doping of Mn in lattice.
Chemical formula | Oxidized (3-δ) | Chemical formula | Reduced (5-δ)/2 | Oxygen loss |
SrFeO3-δ | 2.7227 | Sr2Fe2O5-δ | 2.4347 | 0.2880 |
SrFe0.85Mn0.15O3-δ | 2.6375 | Sr2Fe0.17Mn0.3O5-δ | 2.2989 | 0.3386 |
The oxygen nonstoichiometry is determined using iodometric titration. |
Fig. 2a shows the conductivity of sintered samples in the temperature range of 200 to 800 ℃ in 5%H2/Ar. The SrFeO3-δ and SrFe0.85Mn0.15O3-δ samples show typical p-type conduction in air with conductivity reaching ~8 S·cm-1 at 800 ℃. In reducing atmosphere, the conductivity of the two samples both gradually decreases and finally reaches ~1 S·cm-1. Fig. 2b shows that the doping of Mn significantly reduces the re-equilibrium time in the ECR tests. The conductivity shifts from ~0.6 to 1.6 S·cm-1 for SrFe0.85Mn0.15O3-δ while the conductivity shifts from ~1.2 to 2.2 S·cm-1 for the SrFe0.85Mn0.15O3-δ during the conductivity relaxation test. The doping of Mn leads to the increase of oxygen vacancy, which accordingly decreases the concentration of charge carrier of hole and thereby reduces the mixed conductivity. The surface exchange coefficient, k value, of the SrFe0.85Mn0.15O3-δ samples is enhanced by ~10 times to 3.5 × 10-3 cm·s-1 in contrast to 4.7 × 10-4 cm·s-1 for SrFeO3-δ. The increase of oxygen vacancy is favorable to the enhancement of surface oxygen exchange process that is extremely important to electrode activity.
Fig. 3a shows FT-IR spectrum of the CO2 chemisorption on reduced SrFe0.85Mn0.15O3-δ sample at 800 ℃. The band at 2270~2400 cm-1 is associated with CO2 molecule while the wave number at 1440~1600 cm-1 represents the presence of CO32- on sample surface[6]. The chemisorbed CO2 is therefore supposed to be in an intermediate state between the molecular CO2 and carbonate ions. Fig. 3b shows the temperature programmed desorption of the samples in CO2 atmosphere. It is observed that the chemisorption takes place at ~800 ℃ which is normally close to the decomposition temperature of carbonates. And stronger desorption is observed for the Mn-doped sample which further validates the enhancement of CO2 chemisorption with increased oxygen vacancy concentration on oxide surfaces. We further correlate the desorption volume of CO2 with the surface areas of materials. The adsorption capacity of CO2 is 0.06 and 0.04 mL·mcatal2 for SrFe0.85Mn0.15O3-δ and SrFeO3-δ materials, respectively.
Direct electrolysis of pure CO2 is studied based on SrFeO3-δ and SrFe0.85Mn0.15O3-δ cathodes at 800 ℃. Fig. 4a shows the typical I-V curves of CO2 electrolysis with the two cathodes. For SrFe0.85Mn0.15O3-δ cathode, the current density reaches 0.53 A·cm-2 at 1.6 V which is much higher than 0.44 A·cm-2 based on the SrFeO3-δ cathode under same conditions. This indicates that the Mn-doped cathode enhances CO2 electrolysis through improving electrode activity including surface oxygen exchange process and chemisorption in composite cathode. Fig. 4b shows the short-term performance of CO2 electrolysis under different applied voltages, which further confirms the enhanced current densities with Mn-doped cathode. Fig. 4c and 4d show the production of CO and the Faradaic efficiency with the two cathodes. The production of CO reaches 2.25 mL·min-1·cm-2 for SrFe0.85Mn0.15O3-δ, which is ~20% higher than 1.92 mL·min-1·cm-2 for SrFeO3-δ at 1.5 V. The maximum current efficiency reaches 82.3% and 74.8% for SrFe0.85Mn0.15O3-δ and SrFeO3-δ cathodes at 1.1~1.5 V, respectively.
Fig. 5 presents the AC impedance of CO2 electrolysis recorded at 1.2~1.6 V. In general, the values of Rs are generally stable while the Rp values considerably decrease with the voltage increasing to 1.5 V. We observe the Rp values at 0.62 and 0.46 Ω·cm2 for SrFeO3-δ and SrFe0.85Mn0.15O3-δ cathodes at 1.5 V, respectively, which is comparable to the electrode activity of Sr2Fe1.6Mo0.5O6-δ for CO2 electrolysis[24]. The doping of Mn effectively improves electrode activity and therefore reduces the electrode polarization resistance. Fig. 6a shows the cell microstructure with a configuration of the SrFe0.85Mn0.15O3-δ/LSGM/(La0.8Sr0.2)0.95MnO3-δ, which presents the uniform porous electrode microstructure and very dense electrolyte support. Fig. 6b shows the long-term performance of CO2 electrolysis at 1.3 V at 800 ℃. No degradation is observed even after operation of 100 hours, which further indicates the good stability of the Mn-doped cathode.
In this work, enhanced CO2 electrolysis is achieved with Mn-doped SrFe0.85Mn0.15O3-δ cathode. The doping of Mn increases the concentration of oxygen vacancy and surface oxygen exchange process, which therefore improves the electrode activity toward CO2 splitting. The increase of oxygen vacancy also facilitates the chemisorption of CO2 with the desorption temperature at ~800 ℃. We then demonstrate enhanced CO2 electrolysis with no degradation being observed even after high temperature operation of 100 hours.
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doi: 10.1016/j.ijhydene.2013.12.168
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doi: 10.1016/j.jpowsour.2006.10.006
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doi: 10.1016/j.apcata.2005.08.003
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doi: 10.1016/j.ssi.2010.04.001
Oskouyi, O. E.; Maghsoudipour, A.; Shahmiri, M.; Hasheminiasari, M. Preparation of YSZ electrolyte coating on conducting porous Ni-YSZ cermet by DC and pulsed constant voltage electrophoretic deposition process for SOFCs applications. J. Alloys Compd. 2019, 795, 361–369.
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doi: 10.1039/C2EE22547F
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doi: 10.1016/j.ijhydene.2018.07.148
Tian, Y.; Zhen, H.; Zhang, L.; Chi, B.; Li, J. Direct electrolysis of CO2 in symmetrical solid oxide electrolysis cell based on La0.6Sr0.4Fe0.8Ni0.2O3-δ electrode. J. Electrochem. Soc. 2018, 165, F17–F23.
doi: 10.1149/2.0351802jes
Zhang, L.; Zhu, X.; Cao, Z. Q.; Wang, Z.; Li, W.; Zhu, L.; Li, P.; Huang, X.; Lu, Z. Pr and Ti co-doped strontium ferrite as a novel hydrogen electrode for solid oxide electrolysis cell. Electrochim. Acta 2017, 232, 542–549.
doi: 10.1016/j.electacta.2017.02.168
Li, Z.; Ye, L. T.; Xie, K. Perovskite Sr0.9Fe0.9Zr0.1O3-δ: redox-stable structure, oxygen vacancy, electrical properties and steam electrolysis performance. Chin. J. Struct. Chem. 2018, 37, 65–74.
Gan, L.; Ye, L.; Ruan, C.; Chen, S.; Xie, K. Redox-reversible iron orthovanadate cathode for solid oxide steam electrolyzer. Adv. Sci. 2016, 3, 1500186–6.
doi: 10.1002/advs.201500186
Xiao, G.; Liu, Q.; Wang, S.; Komvokis, V. G.; Amiridis, M. D.; Heyden, A.; Ma, S.; Chen, F. Synthesis and characterization of Mo-doped SrFeO3-δ as cathode materials for solid oxide fuel cells. J. Power Sources 2012, 202, 63–69.
doi: 10.1016/j.jpowsour.2011.11.021
Lu, J.; Zhu, C.; Pan, C.; Lin, W.; Lemmon, J. P.; Chen, F.; Li, C.; Xie, K. Highly efficient electrochemical reforming of CH4/CO2 in a solid oxide electrolyser. Sci. Adv. 2018, 4, eaar5100–10.
doi: 10.1126/sciadv.aar5100
Zhu, C.; Hou, S.; Hu, X.; Lu, J.; Chen, F.; Xie, K. Electrochemical conversion of methane to ethylene in a solid oxide electrolyzer. Nat. Commun. 2019, 10, 1173–8.
doi: 10.1038/s41467-019-09083-3
Maslan, S.; Sira, M.; Skalicka, T.; Bergsten, T. Four-terminal pair digital sampling impedance bridge up to 1M Hz. IEEE Trans. Instrum. Meas. 2019, 68, 1860–1869.
doi: 10.1109/TIM.2019.2908649
Saher, S.; Naqash, S.; Boukamp, B. A.; Hu, B.; Xia, C.; Bouwmeester, H. J. M. Influence of ionic conductivity of the nano-particulate coating phase on oxygen surface exchange of La0.58Sr0.4Co0.2Fe0.8O3-δ. J. Mater. Chem. A 2017, 5, 4991–4999.
doi: 10.1039/C6TA10954C
Li, M.; Sun, Z.; Yang, W.; Hong, T.; Zhu, Z.; Zhang, Y.; Wu, X.; Xia, C. Mechanism for the enhanced oxygen reduction reaction of La0.6Sr0.4Co0.2Fe0.8O3-δ by strontium carbonate. Phys. Chem. Chem. Phys. 2017, 19, 503–509.
doi: 10.1039/C6CP06204K
Schmidt, M.; Campbell, S. J. Crystal and magnetic structures of Sr2Fe2O5 at elevated temperature. J. Solid State Chem. 2001, 156, 292–304.
doi: 10.1006/jssc.2000.8998
Nazzal, A. I.; Lee, V. Y.; Engler, E. M.; Jacowitz, R. D.; Tokura, Y.; Torrance, J. B. New procedure for determination of [Cu-O]+p charge and oxygen-content in high-TC copper oxides. Physica C 1988, 153, 1367–1368.
Myung, J.; Neagu, D.; Miller, D. N.; Irvine, J. T. S. Switching on electrocatalytic activity in solid oxide cells. Nature 2016, 537, 528–531.
doi: 10.1038/nature19090
Zhou, Y.; Zhou, Z.; Song, Y.; Zhang, X.; Guan, F.; Lv, H.; Liu, Q.; Miao, S.; Wang, G.; Bao, X. Enhancing CO2 electrolysis performance with vanadium-doped perovskite cathode in solid oxide electrolysis cell. Nano Energy 2018, 50, 43–51.
doi: 10.1016/j.nanoen.2018.04.054
Vollestad, E.; Strandbakke, R.; Tarach, M.; Catalan-Martinez, D.; Fontaine, M. L.; Beeaff, D.; Clark, D. R.; Serra, J. M.; Norby, T. Mixed proton and electron conducting double perovskite anodes for stable and efficient tubular proton ceramic electrolysers. Nat. Mater. 2019, 18, 752–759.
doi: 10.1038/s41563-019-0388-2
Weng, Z.; Wu, Y.; Wang, M.; Jiang, J.; Yang, K.; Huo, S.; Wang, X. F.; Ma, Q.; Brudvig, G. W.; Batista, V. S.; Liang, Y.; Feng, Z.; Wang, H. Active sites of copper-complex catalytic materials for electrochemical carbon dioxide reduction. Nat. Commun. 2018, 9, 415–8.
doi: 10.1038/s41467-018-02819-7
Zheng, Y.; Wang, J.; Yu, B.; Zhang, W.; Chen, J.; Qiao, J.; Zhang, J. A review of high temperature co-electrolysis of H2O and CO2 to produce sustainable fuels using solid oxide electrolysis cells (SOECs): advanced materials and technology. Chem. Soc. Rev. 2017, 46, 1427–1463.
doi: 10.1039/C6CS00403B
Ye, L.; Zhang, M.; Huang, P.; Guo, G.; Hong, M.; Li, C.; Irvine, J. T. S.; Xie, K. Enhancing CO2 electrolysis through synergistic control of non-stoichiometry and doping to tune cathode surface structures. Nat. Commun. 2017, 8, 14785–8.
doi: 10.1038/ncomms14785
Liu, S.; Liu, Q.; Luo, J. The excellence of La(Sr)Fe(Ni)O3 as an active and efficient cathode for direct CO2 electrochemical reduction at elevated temperatures. J. Mater. Chem. A 2017, 5, 2617–2680.
Meng, X.; Gong, X.; Yang, N.; Yin, Y.; Tan, X.; Ma, Z. F. Carbon-resistant Ni-YSZ/Cu-CeO2-YSZ dual-layer hollow fiber anode for micro tubular solid oxide fuel cell. Int. J. Hydrogen Energy 2014, 39, 3879–3886.
doi: 10.1016/j.ijhydene.2013.12.168
Laosiripojana, N.; Assabumrungrat, S. Catalytic steam reforming of methane, methanol, and ethanol over Ni/YSZ: the possible use of these fuels in internal reforming SOFC. J. Power Sources 2007, 163, 943–951.
doi: 10.1016/j.jpowsour.2006.10.006
Hecht, E. S.; Gupta, G. K.; Zhu, H. Y.; Dean, A. M.; Kee, R. J.; Maier, L.; Deutschmann, O. Methane reforming kinetics within a Ni-YSZ SOFC anode support. Appl. Catal. A 2005, 295, 40–51.
doi: 10.1016/j.apcata.2005.08.003
Hauch, A.; Mogensen, M. Ni/YSZ electrode degradation studied by impedance spectroscopy effects of gas cleaning and current density. Solid State Ionics 2010, 181, 745–753.
doi: 10.1016/j.ssi.2010.04.001
Oskouyi, O. E.; Maghsoudipour, A.; Shahmiri, M.; Hasheminiasari, M. Preparation of YSZ electrolyte coating on conducting porous Ni-YSZ cermet by DC and pulsed constant voltage electrophoretic deposition process for SOFCs applications. J. Alloys Compd. 2019, 795, 361–369.
doi: 10.1016/j.jallcom.2019.04.334
Bidrawn, F.; Kim, G.; Corre, G.; Irvine, J. T. S.; Vohs, J. M.; Gorte, R. J. Efficient reduction of CO2 in a solid oxide electrolyzer. Electrochem. Solid State Lett. 2008, 11, B167–B170.
doi: 10.1149/1.2943664
Xie, K.; Umezawa, N.; Zhang, N.; Reunchan, P.; Zhang, Y.; Ye, J. Self-doped SrTiO3−δ photocatalyst with enhanced activity for artificial photosynthesis under visible light. Energy Environ. Sci. 2011, 4, 4211–4219.
doi: 10.1039/c1ee01594j
Wang, Y.; Liu, T.; Fang, S.; Chen, F. Syngas production on a symmetrical solid oxide H2O/CO2 coelectrolysis cell with Sr2Fe1.5Mo0.5O6-Sm0.2Ce0.8O1.9 electrodes. J. Power Sources 2016, 305, 240–248.
doi: 10.1016/j.jpowsour.2015.11.097
Tsekouras, G.; Neagu, D.; Irvine, J. T. S. Step-change in high temperature steam electrolysis performance of perovskite oxide cathodes with exsolution of B-site dopants. Energy Environ. Sci. 2013, 6, 256–266.
doi: 10.1039/C2EE22547F
Zhu, C.; Hou, S.; Hou, L.; Xie, K. Perovskite SrFeO3-δ decorated with Ni nanoparticles for high temperature carbon dioxide electrolysis. Int. J. Hydrogen Energy 2018, 43, 17040–17047.
doi: 10.1016/j.ijhydene.2018.07.148
Tian, Y.; Zhen, H.; Zhang, L.; Chi, B.; Li, J. Direct electrolysis of CO2 in symmetrical solid oxide electrolysis cell based on La0.6Sr0.4Fe0.8Ni0.2O3-δ electrode. J. Electrochem. Soc. 2018, 165, F17–F23.
doi: 10.1149/2.0351802jes
Zhang, L.; Zhu, X.; Cao, Z. Q.; Wang, Z.; Li, W.; Zhu, L.; Li, P.; Huang, X.; Lu, Z. Pr and Ti co-doped strontium ferrite as a novel hydrogen electrode for solid oxide electrolysis cell. Electrochim. Acta 2017, 232, 542–549.
doi: 10.1016/j.electacta.2017.02.168
Li, Z.; Ye, L. T.; Xie, K. Perovskite Sr0.9Fe0.9Zr0.1O3-δ: redox-stable structure, oxygen vacancy, electrical properties and steam electrolysis performance. Chin. J. Struct. Chem. 2018, 37, 65–74.
Gan, L.; Ye, L.; Ruan, C.; Chen, S.; Xie, K. Redox-reversible iron orthovanadate cathode for solid oxide steam electrolyzer. Adv. Sci. 2016, 3, 1500186–6.
doi: 10.1002/advs.201500186
Xiao, G.; Liu, Q.; Wang, S.; Komvokis, V. G.; Amiridis, M. D.; Heyden, A.; Ma, S.; Chen, F. Synthesis and characterization of Mo-doped SrFeO3-δ as cathode materials for solid oxide fuel cells. J. Power Sources 2012, 202, 63–69.
doi: 10.1016/j.jpowsour.2011.11.021
Lu, J.; Zhu, C.; Pan, C.; Lin, W.; Lemmon, J. P.; Chen, F.; Li, C.; Xie, K. Highly efficient electrochemical reforming of CH4/CO2 in a solid oxide electrolyser. Sci. Adv. 2018, 4, eaar5100–10.
doi: 10.1126/sciadv.aar5100
Zhu, C.; Hou, S.; Hu, X.; Lu, J.; Chen, F.; Xie, K. Electrochemical conversion of methane to ethylene in a solid oxide electrolyzer. Nat. Commun. 2019, 10, 1173–8.
doi: 10.1038/s41467-019-09083-3
Maslan, S.; Sira, M.; Skalicka, T.; Bergsten, T. Four-terminal pair digital sampling impedance bridge up to 1M Hz. IEEE Trans. Instrum. Meas. 2019, 68, 1860–1869.
doi: 10.1109/TIM.2019.2908649
Saher, S.; Naqash, S.; Boukamp, B. A.; Hu, B.; Xia, C.; Bouwmeester, H. J. M. Influence of ionic conductivity of the nano-particulate coating phase on oxygen surface exchange of La0.58Sr0.4Co0.2Fe0.8O3-δ. J. Mater. Chem. A 2017, 5, 4991–4999.
doi: 10.1039/C6TA10954C
Li, M.; Sun, Z.; Yang, W.; Hong, T.; Zhu, Z.; Zhang, Y.; Wu, X.; Xia, C. Mechanism for the enhanced oxygen reduction reaction of La0.6Sr0.4Co0.2Fe0.8O3-δ by strontium carbonate. Phys. Chem. Chem. Phys. 2017, 19, 503–509.
doi: 10.1039/C6CP06204K
Schmidt, M.; Campbell, S. J. Crystal and magnetic structures of Sr2Fe2O5 at elevated temperature. J. Solid State Chem. 2001, 156, 292–304.
doi: 10.1006/jssc.2000.8998
Nazzal, A. I.; Lee, V. Y.; Engler, E. M.; Jacowitz, R. D.; Tokura, Y.; Torrance, J. B. New procedure for determination of [Cu-O]+p charge and oxygen-content in high-TC copper oxides. Physica C 1988, 153, 1367–1368.
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Hao Sun , Xiaoxue Li , Baoyu Wu , Kai Zhu , Yinyi Gao , Tianzeng Bao , Hongbin Wu , Dianxue Cao . Direct regeneration of spent LiFePO4 cathode material via a simple solid-phase method. Chinese Chemical Letters, 2025, 36(6): 110041-. doi: 10.1016/j.cclet.2024.110041
Yajun Hou , Chuanzheng Zhu , Qiang Wang , Xiaomeng Zhao , Kun Luo , Zongshuai Gong , Zhihao Yuan . ~2.5 nm pores in carbon-based cathode promise better zinc-iodine batteries. Chinese Chemical Letters, 2024, 35(5): 108697-. doi: 10.1016/j.cclet.2023.108697
Shenghui Tu , Anru Liu , Hongxiang Zhang , Lu Sun , Minghui Luo , Shan Huang , Ting Huang , Honggen Peng . Oxygen vacancy regulating transition mode of MIL-125 to facilitate singlet oxygen generation for photocatalytic degradation of antibiotics. Chinese Chemical Letters, 2024, 35(12): 109761-. doi: 10.1016/j.cclet.2024.109761
Yuan Dong , Mutian Ma , Zhenyang Jiao , Sheng Han , Likun Xiong , Zhao Deng , Yang Peng . Effect of electrolyte cation-mediated mechanism on electrocatalytic carbon dioxide reduction. Chinese Chemical Letters, 2024, 35(7): 109049-. doi: 10.1016/j.cclet.2023.109049
Wei-Jia Wang , Kaihong Chen . Molecular-based porous polymers with precise sites for photoreduction of carbon dioxide. Chinese Chemical Letters, 2025, 36(1): 109998-. doi: 10.1016/j.cclet.2024.109998
Yuchen Zhang , Lifeng Ding , Zhenghe Xie , Xin Zhang , Xiaofeng Sui , Jian-Rong Li . Porous sorbents for direct capture of carbon dioxide from ambient air. Chinese Chemical Letters, 2025, 36(3): 109676-. doi: 10.1016/j.cclet.2024.109676
Jianjun Fang , Kunchen Xie , Yongli Song , Kangyi Zhang , Fei Xu , Xiaoze Shi , Ming Ren , Minzhi Zhan , Hai Lin , Luyi Yang , Shunning Li , Feng Pan . Break the capacity limit of Li4Ti5O12 anodes through oxygen vacancy engineering. Chinese Journal of Structural Chemistry, 2025, 44(2): 100504-100504. doi: 10.1016/j.cjsc.2024.100504
Jinshu Huang , Zhuochun Huang , Tengyu Liu , Yu Wen , Jili Yuan , Song Yang , Hu Li . Modulating single-atom Co and oxygen vacancy coupled motif for selective photodegradation of glyphosate wastewater to circumvent toxicant residue. Chinese Chemical Letters, 2025, 36(5): 110179-. doi: 10.1016/j.cclet.2024.110179
Ruonan Yang , Jiajia Li , Dongmei Zhang , Xiuqi Zhang , Xia Li , Han Yu , Zhanhu Guo , Chuanxin Hou , Gang Lian , Feng Dang . Grain-refining Co0.85Se@CNT cathode catalyst with promoted Li2O2 growth kinetics for lithium-oxygen batteries. Chinese Chemical Letters, 2024, 35(12): 109595-. doi: 10.1016/j.cclet.2024.109595
Zhuangzhuang Zhang , Yaru Qiao , Jun Zhao , Dai-Huo Liu , Mengmin Jia , Hongwei Tang , Liang Wang , Dongmei Dai , Bao Li . Fluorine-doped K0.39Mn0.77Ni0.23O1.9F0.1 microspheres with highly reversible oxygen redox reaction for potassium-ion battery cathode. Chinese Chemical Letters, 2025, 36(3): 109907-. doi: 10.1016/j.cclet.2024.109907
Ziling Jiang , Shaoqing Chen , Chaochao Wei , Ziqi Zhang , Zhongkai Wu , Qiyue Luo , Liang Ming , Long Zhang , Chuang Yu . Enabling superior electrochemical performance of NCA cathode in Li5.5PS4.5Cl1.5-based solid-state batteries with a dual-electrolyte layer. Chinese Chemical Letters, 2024, 35(4): 108561-. doi: 10.1016/j.cclet.2023.108561
Jian Yang , Guang Yang , Zhijie Chen . Capturing carbon dioxide from air by using amine-functionalized metal-organic frameworks. Chinese Journal of Structural Chemistry, 2024, 43(5): 100267-100267. doi: 10.1016/j.cjsc.2024.100267
Yue Zhang , Xiaoya Fan , Xun He , Tingyu Yan , Yongchao Yao , Dongdong Zheng , Jingxiang Zhao , Qinghai Cai , Qian Liu , Luming Li , Wei Chu , Shengjun Sun , Xuping Sun . Ambient electrosynthesis of urea from carbon dioxide and nitrate over Mo2C nanosheet. Chinese Chemical Letters, 2024, 35(8): 109806-. doi: 10.1016/j.cclet.2024.109806
Xiaxia Xing , Xiaoyu Chen , Zhenxu Li , Xinhua Zhao , Yingying Tian , Xiaoyan Lang , Dachi Yang . Polyethylene imine functionalized porous carbon framework for selective nitrogen dioxide sensing with smartphone communication. Chinese Chemical Letters, 2024, 35(9): 109230-. doi: 10.1016/j.cclet.2023.109230
Weidan Meng , Yanbo Zhou , Yi Zhou . Green innovation unleashed: Harnessing tungsten-based nanomaterials for catalyzing solar-driven carbon dioxide conversion. Chinese Chemical Letters, 2025, 36(2): 109961-. doi: 10.1016/j.cclet.2024.109961