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Supercapacitors, also known as electrochemical capacitors, are new energy storage components between traditional capacitors and batteries, attracting a great deal of attention in recent years [1]. However, the main problem facing supercapacitors electrode materials is the low energy density. For both EDLCs and pseudocapacitors, electrodes with large surface area, good electrical conductivity and high-mass loading active materials are extremely desired to enhance the capacitance and further storage energy density [2]. Recently, porous oxide films formed on stainless steel (SS) foils attracted attention as promising nanoporous active material due to theoretically high specific capacitance, however, the nanoporous oxide films on SS foils by galvanostatic anodization typically suffer from low capacitance due to the limited layer thickness [3-4], which greatly restricts the mass of active materials thus large number charge storage sites. Therefore, ultra-thick nanostructured anodic films are highly desired to develop high-performance supercapacitors. In the experiments, the SUS 304-type SS foils containing C (0.07 wt%), Cr (17.01wt%), Ni (8.02%) and Fe balance was used as the anodizing substrate. Prior to anodization, all samples were ultrasonically cleaned in acetone and distilled water respectively for 15 minutes followed by air drying. Then, the anodization of SS foils was carried out in ethylene glycol containing 0.1 M distilled water and 0.1 M NH4F using a two-electrode cell. The SS foils worked as anode and graphite plate (2 mm in thickness) as cathode. Both were immersed in as-made electrolyte (10 mm in depth) parallel with each other. The distance between the two electrodes was fixed at 3.5 cm. The potential of 50 V was employed for 1, 2 and 3 h, respectivel. During the anodization process, the long-term anodization was kept by slightly decreasing electrolyte temperature to rescrict the temperature rise. The as-fabricated samples were soaked in 99.9% ethanol for 1 h followed by annealing at 500℃ in air for 3h. Fig.1 presents the SEM images of self-organized porous anodic films formed on the surface of SS foils by constant potential anodization of 50 V for 1, 2 and 3 h, respectively. The formed self-organized pores all exhibited a quasi-honeycomb structure with pore diameters mainly ranging from 45 to 60 nm as shown in Fig. 1a. The thickness of 8.9, 16.8, 26.9 μm anodic layer was respectively formed at 50 V for 1, 2, 3 h as shown in Fig. 1b-d. The achieved maximum thickness is over 7 times higher than the reported value obtained from galvanostatic anodization [5]. However, some cracks were observed across the thick anodic films, which were possibly formed by the residual stress produced during film growing process and further amplified during subsequent annealing process. Fig. 2 (a), (b) and (c) show the C-V curves of the anodic layers formed at 50 V for 1, 2 and 3 h at different scan rates, respectively. Clearly, the C-V curves exhibit a nearly symmetric CV plots when tested as a binder-free electrode, indicating good reversibility of faradaic redox reactions. The anodic layers exhibit the specific area capacitance ~ 81, 157 and 215 mF cm-2 at the current density of 1 mA cm-2. Furthermore, the thickest one surprisingly exhibited the higher area capacitance ~ 215 mF cm-2 at 1 mA cm-2 and ~ 128 mF cm-2 at 4 mA cm-2, and the capacitance still retained 63.9% of its initial value after 1000 cycles. The obtained highest capacitance is 3 times higher than the reported value obtained from galvanostatic anodization [5]. In summary, ultra-thick nanostructured anodic films have been fabricated on 304 stainless steel via long-term constant-potential anodization instead of galvanostatic anodization. The long-term anodization was kept by slightly decreasing electrolyte temperature to rescrict the temperature rise during anodization process. When tested as a binder-free electrode, the formed anodic layers exhibit the highest area capacitance ~ 215 mF cm-2 at 1 mA cm-2, and the capacitance still retained 63.9% of its initial value after 1000 cycles. References [1] B. Sarma, Y.R. Smith, A.L. Jurovitzki, R.S. Ray, S.K. Mohanty, M. Misra, Journal of Power Sources, 236 (2013) 103-111. [2] K.Y. Xie, J. Li, Y.Q. Lai, W. Lu, Z.A. Zhang, Y.X. Liu, L.M. Zhou, H.T. Huang, Electrochemistry Communications, 13 (2011) 657-660. [2] X. Lu, G. Wang, T. Zhai, M. Yu, J. Gan, Y. Tong, Y. Li, Nano Lett, 12 (2012) 1690-1696. [3] K. Kure, Y. Konno, E. Tsuji, P. Skeldon, G.E. Thompson, H. Habazaki, Electrochemistry Communications, 21 (2012) 1-4. [4] H. Asoh, M. Nakatani, S. Ono, Surf Coat Tech, 307 (2016) 441-451. [5] A.A. Yadav, A.C. Lokhande, J.H. Kim, C.D. Lokhande, J Colloid Interface Sci, 473 (2016) 22-27. Figure 1

Supercapacitors, as an energy storage device, have attracted growing interests [1]. Recently, iron oxides (a-Fe2O3 and Fe3O4) have been demonstrated to present comparable pseudocapacitive properties [2]. It was further observed that nanoporous oxide layers have been obtained on various SS substrates by electrochemical anodization process. They can provide more reaction sites due to high surface area, and acceptable electron conductivity due to multiple valence states of formed Fe3O4 for potential supercapacitor electrodes. Meanwhile, it has been envisaged that annealing at various temperatures may induce morphologgical modification and crystal-phase transition, which will strongly influence the supercapacitance behavior [3]. However, the effects of annealing temperature on supercapacitance behavior of anodic oxide films have not been well studied. In the experiments, SUS 304-type SS foils were used as the anode for prorous formation. The anodization of SS foils was carried out in ethylene glycol containing 0.1 M distilled water and 0.1 M NH4F using a two-electrode cell. The SS foils worked as anode and graphite plate as cathode. During the anodization process, the long-term anodization was kept by slightly decreasing electrolyte temperature to rescrict the temperature rise. The as-fabricated samples were soaked in 99.9% ethanol for 1 h followed by annealing at 200-600℃ in air for 3h, respectively. Fig.1 presents the SEM images of self-organized porous anodic films formed on the surface of SS foils by constant potential anodization of 50 V for 1 h, respectively annealed at 200-600℃ in air. The self-organized pores exhibited a quasi-honeycomb structure with pore diameters ranging from 45 to 60 nm as shown in Fig. 1a. As shown in Fig. 1b, the thickness of 8.12 μm anodic layer was formed at 50 V for 1h and some cracks were further clearly observed across the anodic films by the residual stress produced during film growing process and further amplified during subsequent annealing process. Remarkably, the decrease of the pore size from the top to the bottom of the porous anodic film was clearly observed by SEM pictures shown in Fig. 1c, the pore size varies from 53±10nm (top) to 33±7nm (bottom). An anodic etching model will be applied to explain the phenonomenon. XRD spectra further reveals the annealed anodic films own crystalline structures, which are predominantly composed of three phases of hematite (Fe2O3), eskolaite (Cr2O3) and spinel (Fe3O4 and FeCr2O4), which was clearly increased with the increasing annealing temperature. Fig. 2 (a) shows the C-V curves of the anodic layers formed at different annealing temperature. When tested as a binder-free electrode, all C-V curves exhibit a nearly symmetric CV plots, indicating good reversibility of faradaic redox reactions. Clearly, the anodic layer annealed at 400℃ exhibits the maximum specific area capacitance among the five samples, which can be explained by the increased amount of Fe2O3 and Fe3O4. Fig. 2 (b) shows the C-V curves of the anodic layers (400℃) recorded at the scan rates from 5 to 100 mV s-1. The enclosed area under the CV curve increases with the scan rate increases from 5 to 100 mV s-1. Similar results were observed in GCD plots as shown in Fig. 2 (c) and (d). The anodic layers exhibit the specific area capacitance ~ 54.5, 145.3, 80.6 and 18.3mF cm-2 at 1 mA cm-2, resepectively for the annealing temperature from 300-600℃. The optimum one exhibited the higher area capacitance ~ 145.3 mF cm-2 at 1 mA cm-2 and ~ 76 mF cm-2 at 4 mA cm-2, and the capacitance still retained 53.3% of its initial value after 1000 cycles. The Nyquist plots are presented in Fig. 2e to assess the resistance and capacitance of the formed anodic films. The lower resistance of anodic film annealed at 600℃ was attributed to the increased amount of high conductive Fe3O4. In summary, nanostructured anodic films have been fabricated on 304 stainless steel via constant-potential anodization instead of galvanostatic anodization. The supercapacitance behavior of anodic film is strongly dependent on the annealing temperature. When tested as a binder-free electrode, the optimum anodic layers (400℃) exhibit the highest area capacitance ~ 145.3 mF cm-2 at 1 mA cm-2, and the capacitance still retained 53.3% of its initial value after 1000 cycles. References [1] B. Sarma, Y.R. Smith, A.L. Jurovitzki, R.S. Ray, S.K. Mohanty, M. Misra, Journal of Power Sources, 236 (2013) 103-111. [2] K.Y. Xie, J. Li, Y.Q. Lai, W. Lu, Z.A. Zhang, Y.X. Liu, L.M. Zhou, H.T. Huang, Electrochemistry Communications, 13 (2011) 657-660. [3] B. Sarma, A. L. Jurovitzki, Y. R. Smith, R. S. Ray, M. Misra, Journal of Power Sources, 272 (2014) 766-775. Figure 1

Supercapacitors (also known as ultracapacitors) are considered to be the most promising candidate for alternative energy storage/conversion devices [1-3]. However, the low energy density limits their applications that require high cycle life and power density. Compared with pseudocapacitors, the working mechanism of electric double layer capacitors (EDLCs) is a physical process, and it has the advantages of fast charging and discharging, good cycle performance, low cost, and no degradation after tens of thousands of cycles. For EDLCs, highly porous carbon materials are commonly used as supercapacitor electrodes. In recent decades, lots of works has been focused on improving the capacitive performance of porous carbon electrodes by the introduction of good-performance electrode materials. However, the relatively easily produced and low-cost carbon materials with proper porosity and good electrical conductivity are highly desirable. In this work, glucose was firstly used as the precursor to produce porous carbon electrodes by hydrothermal carbonization (HTC) at 260℃, which is accomplished under mild and simple condition and is adaptable for wide feedstocks. Then, the porosity of the carbon electrodes has been improved by chemical activation with different amount of KOH at 800℃. The effects of different mass ratio of glucose to KOH (1:0, 1:1, 1:2, 1:3 and 1:1) on chemical activation efficiency have been studied. Scanning electron microscopy (SEM) images and Raman spectra of the porous carbon electrodes before and after activation are shown Fig. 1. Clearly, the glucose-derived porous carbon exhibits a sphere shape, and the pore structure has been greatly changed before and after KOH activation. It is notable that microspores of the porous carbon sphere were clearly enlarged after activation, and the enlarged mesopores are proper candidate as supercapacitor electrode. Fig. 2 presents the current-voltage (C-V) curves of different glucose-derived porous carbon microelectrodes at different scan rate in 1M Na2SO4electrolyte. For all samples, the CV curves exhibits a symmetric rectangular shape, which indicates the behavior of electric double layer capacitors. The increased corresponding currents of glucose-derived porous carbon indicates the specific capacitance is increased after KOH activation. The specific capacitances of glucose-derived porous carbon with 1:3 (mass ratios of glucose to KOH) is reached 207 F/g. The The electric capacitance is strongly associated with the improved porous structure after KOH activation. References [1] T. Tooming, T. Thomberg, H. Kurig, E. Lust High power density supercapacitors based on the carbon dioxide Activated D-glucose derived carbon electrodes and 1-ethyl-3-methylimidazo-lium tetrafluoroborate ionic liquid , Journal of Power Sources, 280 (2015) 667-677 [2] Y.L. Wang, H.Q. Xuan, G.X. Lin, F. Wang, Z. Chen, X.P. Dong, A melamine-assisted chemical blowing synthesis of N-doped activated carbon sheets for supercapacitor application, Journal of Power Sources, 319 (2016) 262-270 [3] M. Enterría, F.J. Martín-Jimeno, F. Su arez-García, J.I. Paredes, M.F.R. Pereira, J.I. Martinsc, A.Martínez-Alonso, J.M.D. Tasc on, J.L. Figueiredo, Effect of nanostructure on the supercapacitor performance of activated carbon xerogels obtained from hydrothermally carbonized glucose-graphene oxide hybrids, Carbon, 105 (2016) 474-483 Figure 1

Supercapacitors, also known as electrochemical capacitors, are new energy storage components between traditional capacitors and batteries, attracting a great deal of attention in recent years [1]. However, the main problem facing supercapacitors electrode materials is the low energy density. Lots of efforts have been made to increase the electrochemical capacitance of the electrode materials, such as fabricate nanotubes, nanowires, and nano-sheet to develop large-surface-area nanostructured electrodes or mix two or more kind of good electrode materials to produce composite electrodes [2-3]. Therefore, combining large-surface-area nanostructure and good composite electrodes is good potential approach to develop high-performance micro supercapacitors. In this work, highly ordered TiO2 nanotube arrays (TNAs) were firstly fabricated with anodic oxidation method on Ti foils (1 cm × 1 cm), which were used as high-surface-area substrate. The Ti foil was anodized at a constant potential of 50 V for 20 h in a two-electrode system, using an aqueous electrolytic containing 0.25 wt.% NH4F and 2 vol.% H2O. Then, hydrogen electrochemical doping was performed to improve the electric double-layer capacitance of TiO2 nanotube films. TiO2 nanotube films were used as cathodes while the carbon rod as anode. The gap between two electrodes was 2.5cm, and a voltage of 5 V was applied for 30 s in a 0.5 M Na2SO4 solution. Then, nickel oxide was deposited through the whole TiO2 nanotube films in 0.04M NiCl2 through the method of differential pulse voltammetry. Finally, the hydrogenated TiO2/NiO (H-TiO2/NiO) nanotube array composite electrode was successfully fabricated. Fig.1 (a) and (b) presents sannning electron microscope (SEM) images of the TiO2 nanotube films before and after electrochemical hydrogenation. The pristine TiO2 nanotubes have an inner diameter of ∼120 nm and a tube length of about 10um. Obviously, there is significant change of the morphology of TiO2 nanotubes after the electrochemical hydrogenation. Fig.1 (c) and (d) show the SEM images of hydrogenated TiO2 nanotubes after NiO deposition. The narrower inner diameter of TiO2 nanotube obviously indicates NiO was deposited through the inner and outer walls of TiO2 nanotubes. Fig.2 (a), (b) and (c) show the C-V curves of pristine TiO2, H-TiO2 and H-TiO2/NiO nanotube films at different scan rates. Clearly, the C-V curves of pristine TiO2 nanotubes are close to rectangular shape, which exhibits the behavior of electric double layer capacitors. However, the specific capacitance, which was calculated to be 0.6 mF cm-2 at 0.08 mA cm-2, is quite low due to the low corresponding current. The C-V curves of H-TiO2 nanotubes exhibit perfect capacitance behavior of electric double layer capacitors and much higher current response. The specific capacitance was calculated to be 71 mF/cm2 at 0.5 mA cm-2, which was significantly enhanced after hydrogen doping. The C-V curves of H-TiO2/NiO nanotubes exhibit typical pseudo capacitance behavior, and the specific capacitance was calculated to be 285mF/cm2 at 0.5 mA cm-2 after NiO deposition shown in the EDX elemental mapping in Fig.2 (d). In summary, the electrochemical behaviors of pristine TiO2, H-TiO2 and H-TiO2/NiO nanotube films have been fabricated and characterized by SEM and electrochemical measurements. The specific capacitance of TiO2 nanotube films can be greatly enhanced from 0.6 mF cm-2 at 0.08mA cm-2 to 71 mF/cm2 and further 285mF/cm2 at 0.5mA/cm2 after electrochemical hydrogenation and NiO deposition. References [1] Campos J W, Beidaghi M, Hatzell K B, et al. Investigation of carbon materials for use as a flowable electrode in electrochemical flow capacitors[J]. Electrochimica Acta, 2013, 98(16):123–130. [2] Lu X, Zheng D, Zhai T, et al. Large-area manganese oxide nanorod arrays as high-performance electrochemical supercapacitor[J]. Energy & Environmental Science, 2011, 4(8):2915-2921. [3]Gonzalez Z, Ferrari B, Sanchez-Herencia A J, et al. Use of Polyelectrolytes for the Fabrication of Porous NiO Films by Electrophoretic Deposition for Supercapacitor Electrodes[J]. Electrochimica Acta, 2016, 211:110-118. Figure 1

In recent years, environmental problems induced by organic pollutants have become an important problem for our society. Semiconductor photochemical treatment is a potential technology for solving the environmental issues. Therefore, lots of efforts have been devoted to develop high-efficiency visible light assisted semiconductor photocatalysts. Cu2O nanoparticle is a well-known p-type semiconductor with a direct band gap of 2.17eV, which endows it a reasonable alternative for photocatalytic applications [1-3]. However, high recombination rate of the electron-hole pairs excited from Cu2O nanoparticles seriously hinders its practical application. Coupling p-type Cu2O nanoparticles with n-type semiconductor to form a P-N heterojunction for carrier separation and produce appropriate energy level difference for charge transfer from one semiconductor to another is a potential approach to decrease recombination rate for high-efficiency degradation. Graphene-like n-type semiconductor MoS2 multilayered nanoplates are the reasonable alternative due to its tunable bandgap with different layers and large amounts of unsaturated active sites [4-5]. In this work, two-dimensional (2D) MoS2 nanoplates with different multilayer thickness were prepared by liquid exfoliation and gradient centrifugation. Then, the MoS2 nanoplates were utilized to match the energy level of Cu2O nanoparticles to form MoS2/Cu2O nanocomposites, which have been achieved by the method of hydrothermal synthesis. Scanning Electrom Microscope images and X-ray diffraction (XRD) pattern of nanoparticles Cu2O and MoS2/Cu2O nanocomposites are shown in Fig.1. It can be seen that the morphology of Cu2O nanoparticles are truncated octahedron structure and closely attached on MoS2 nanosheets with different thickness, which was obtained at the centrifugation speed of 2000 rpm, 4000 rpm, 6000 rpm and 8000 rpm. The photochemical behaviors of Cu2O nanoparticles and different MoS2/Cu2O nanocomposites are characterized through the degradation behaviors of methyl orange (MO) under visible light irradiation (Fig.2). The experimental results show that the degradation efficiency of MoS2/Cu2O nanocomposites can be improved by optimizing the thickness of MoS2 nanoplates from few layers to bulk. The degradation ratios of MO after 3 h are 57.9%, 61.1%, 92.2%, 95.3%, 93.1%, and correspond respectively to the MoS2/Cu2O nanocomposites in which the MoS2 nanosheets were obtained at the centrifugation speed of 0 rpm, 2000 rpm, 4000 rpm, 6000 rpm and 8000 rpm. The possible reason is that the increasing surface area and bandgap of MoS2 may provide large reaction area and produce appropriate energy level difference, which is beneficial for accelerating the degradation process of methyl orange. In summary, the different MoS2/Cu2O heterojunction nanocomposites were prepared through adjusting the thickness of multilayered MoS2 nanoplates. The results show that the optimized degradation ratio of MO can be greatly improved from 57.9% up to 95.3% after 3h using MoS2/Cu2O nanocomposites in comparison with Cu2O nanoparticles. References [1] J. Singh, M. Srivastava, A. Roychoudhury, D.W. Lee, S.H. Lee, B.D. Malhotra, J. Phys. Chem. B, 117 (2013), 141-152 [2] S. Sun, H. Zhang, L. Tang, X. Zhang, Z. Yang, Phys. Chem. Chem. Phys., 16 (2014), pp. 20424–20428 [3] X.G. Yan, L. Xu, W.Q. Huang, G.F. Huang, Z.M. Yang, S.Q. Zhan, J.P. Long, Mater. Sci. Semicond. Process. 23 (2014), pp. 34–41 [4] Li J, Liu E Z, Ma Y N, et al. Appl. Surf. Sci., 2016, 364:694-702 [5] B. Radisavljevic, A. Radenovic, J. Brivio, V. Giacometti, A. Kis, Nature Nanotechnology, 6 (2011) 147–150. Figure 1

Supercapacitors have attracted significant research interest due to their fast cycling and high power densities, charging and discharging time for millions of cycle [1]. Highly porous carbon materials are commonly used as supercapacitor electrodes due to their high specific surface area and good conductivity. To realize MEMS supercapacitors, a scalable technique for on-chip integrated high-performance microelectrodes are in urgent required. Pyrolyzed patterned photoresist is one attractive way to deposit porous carbon electrode for electrochemical applications. However, current research on pore structure control of photoresist-derived carbon electrodes with large specific capacitance and good cycling performance is rather limited including the problem of uneven porosity [2, 3]. For porous structure control of pyrolyzed photoresist-derived carbon, 200 mg, 300 mg and 400 mg of magnesium citrate nanoparticles were mixed in 10 ml SU-8 photoresist during pyrolysis process respectively.The ultra-thick SU-8 photoresist layer mixed with magnesium citrate was deposited on silicon wafer with multiple spin-coating methods at the rotation speed of 1500 rpm for 35s. Then, the doped SU-8 photoresist was pyrolyzed in a horizontal tube furnace under inert forming gas (95% N2, 5% H2) atmosphere with flow rate of 2000 sccm, which the temperature was programmed from room temperature to 950 oC. Fig. 1 shows the SEM images of pyrolyzed SU-8 photoresist before and after magnesium citrate doping. Fig. 2 presents the Current-Voltage (C-V) curves of carbon microelectrodes at different scan rate in 1M Na2SO4 electrolyte. Clearly, the C-V curves of the carbon electrodes with magnesium citrate doping is more close to symmetric rectangular shape than that without doping, which optimized capacitance is 205mF/cm-2capacitance for the sample (30 mg/ml). Fig. 3 plots the galvanostatic charging and discharging curves of carbon microelectrodes at different current densities. The charging and discharging curve exhibits a near isosceles triangle, which indicates a better irreversible discharging and discharging performance. However, the charging/discharging time of the carbon electrodes with magnesium citrate doping is much longer than that without doping, which indicates the specific surface area of the carbon electrodes was greatly increased after magnesium citrate doping. In summary, carbon microelectrodes derived from pyrolyzed SU-8 photoresist with different doping concentration have been prepared and characterized by SEM and electrochemical technique. The optimized concentration of magnesium citrate nanoparticles in SU-8 photoresist is 30 mg/ml, and optimized capacitance is 205mF/cm-2correspondingly. The high capacitance could be associated with the highly porous structure. References: [1] Jiang S, Shi T, Liu D, et al. Integration of MnO2 thin film and carbon nanotubes to three-dimensional carbon microelectrodes for electrochemical microcapacitors. Journal of Power Sources , 262 (2014): 494-500. [2] Wang S, Hsia B, Carraro C, et al. High-performance all solid-state micro-supercapacitor based on patterned photoresist-derived porous carbon electrodes and an ionogel electrolyte. Journal of Materials Chemistry A 2.21 (2014): 7997-8002. [3] Jin Z, Xun Y, Wei X, et al. Mesoporous carbons derived from citrates for use in electrochemical capacitors. New Carbon Materials, 25.5 (2010): 370-375. Figure 1

Semiconductor photochemical treatment is expected to be a green technology for solving the environmental issues induced by organic pollutants. WO3 are generally considered as an excellent candidate for visible-light photocatalysts [1-3]. However, the activity of pure WO3 has to be improved due to the rapid recombination of the photogenerated electron-hole pairs. In this work, WO3 was loaded with hybrid MoS2-reduced graphene oxide (MoS2-rGO) to form WO3/MoS2-rGOheterojunction composites, in which MoS2 acts as another efficient light absorbing material and rGO as the charge transfer medium to enhance the photocatalytic efficiency [4-5]. In this work, WO3 was prepared by hydrothermal synthesis method with WCl6 as tungsten source and absolute ethanol as solvent, as shown in Fig. 1(a). Clearly, the synthesized WO3 is a monodispersed microsphere structure with an average size of 2-3um. The hybrid MoS2-rGO was prepared by adding graphene during the hydrothermal synthesis process of MoS2 with Na2MoO4·2H2O and thiourea as reacting materials. As shown in Fig. 1(b), the synthesized MoS2 shows a flower-like structure. Finally, the WO3/MoS2-rGO nanocomposites were also prepared by adding the prepared hybrid MoS2-rGO during the hydrothermal synthesis process of WO3. As shown in Fig. 1(c) and (d), the close contact is clearly seen between the microsphere-like WO3 and flower-like hybrid MoS2-rGO, and the second hydrothermal process had no influence on the structure of WO3 and hybrid MoS2-rGO. X-ray diffraction (XRD) patterns and Raman spectra are respectively measured to determine the crystal structure, as shown in Fig.1 (e) and (f). The photochemical behaviors of WO3/MoS2-rGO nanocomposites containing (0, 2%, 5%, 10%, and 20%) of hybrid MoS2-rGO are characterized through the degradation behaviors of rhodamine (RhB) under visible light irradiation (Fig.2). The experimental results clearly show that the degradation efficiency of WO3/MoS2-rGO nanocomposites can be improved by optimizing the mass ratio of WO3 microspheres to hybrid MoS2-rGO flowers. The degradation ratios of RhB after 6 h are 78.2%, 79.5%, 82.6%, 95.6%, 91.8%, correspond respectively to the WO3/MoS2-rGO nanocomposites containing 0, 2%, 5%, 10%, and 20% of hybrid MoS2-rGO. The possible reason is that the formed WO3/MoS2heterojunction structure and charge transfer medium of rGO is beneficial for separating electron-hole pairs for high efficiency degradation In summary, the WO3 microspheres and different WO3/MoS2-rGO nanocomposites have been prepared and characterized through adjusting the mass ratio of WO3 microspheres to hybrid MoS2-rGO flowers. The results show that the optimized degradation ratio of RhB can be greatly improved from 78.2% up to 95.6% after 6h using WO3/MoS2-rGO nanocomposites in comparison with WO3 microspheres. References [1] J. Georgieva, E. Valova, S. Armyanov, N. Philippidis, I. Poulios, S. Sotiropoulos, Journal of Hazardous Materials 211–212 (2012) 30–46. [2] S.Y. Yao, X. Zhang, F.Y. Qu, A. Umar, X. Wu, Journal of Alloys and Compounds 689 (2016) 570–574. [3] S.V. Mohite, V.V. Ganbavle, K.Y. Rajpure, Journal of Alloys and Compounds 655 (2016) 106–113. [4] B. Radisavljevic, A. Radenovic, J. Brivio, V. Giacometti, A. Kis, Nature Nanotechnology, 6 (2011) 147–150. [5] P. Devi, C. Sharma, P. Kumar, M. Kumar, B. K.S. Bansod, M. K. Nayak, M. L. Singla, Journal of Hazardous Materials, 322 (2017) 85–94. Figure 1