Finding long-term solutions to meet the growing energy demands of the human society is one of the greatest challenges of our age. Photocatalysis, a topic of many decades of attention, has recently received renewed and more intense interest in developing innovative solutions towards achieving our sustainability goal. Though immensely inspired by natural photosynthesis, the research on artificial photosynthesis is still in its early stage, and many technological challenges must be solved before it can be applied to large-scale. It has been widely recognized that it is necessary to develop advanced materials and new molecules assembled preferably from earth abundant elements as efficient photocatalysts to accomplish the complex process of solar energy driven water splitting and carbon dioxide reduction. Nanotechnology certainly plays a pivotal role in enabling a rational design of the structures, interfaces and surfaces with controllable features at a length scale comparable to chemical reactions, as shown in this Thematic Series.
See also the Thematic Series:
Electrocatalysis on the nm scale
Figure 1: XRD patterns of (a) pure ZnIn2S4; (b) 0.5 wt % NiS/ZnIn2S4.
Figure 2: TEM images of (a) ZnIn2S4; (b) NiS/ZnIn2S4 and (c) HRTEM image of NiS/ZnIn2S4 (inset: EDS).
Figure 3: XPS spectra of NiS/ZnIn2S4 and ZnIn2S4 (a) survey spectrum and high-resolution spectra for (b) S 2p...
Figure 4: UV–vis diffraction spectra of the pure ZnIn2S4 and 0.25 wt %, 0.5 wt %, 1.0 wt %, 2.0 wt % NiS/ZnIn2...
Figure 5: Amount of hydrogen evolution over (a) pure ZnIn2S4; (b) 0.2 wt % MoS2/ZnIn2S4; (c) mechanical mixtu...
Figure 6: Photocatalytic hydrogen evolution rate over pure ZnIn2S4; ZnIn2S4 with different amounts of NiS: 0....
Figure 7: Amount of hydrogen evolved over 0.5 wt % NiS/ZnIn2S4 system in a 15 h photocatalytic reaction. (Rea...
Figure 8: XRD patterns of 0.5 wt % NiS/ZnIn2S4 (a) before and (b) after photocatalytic hydrogen evolution rea...
Scheme 1: Schematic illustration of proposed mechanism for photocatalytic hydrogen evolution over NiS/ZnIn2S4...
Figure 1: XRD patterns of Pt@TiO2 and Pt/TiO2 samples.
Figure 2: TEM and SEM images of the Pt@TiO2 sample. (A) (B) TEM images of Pt@TiO2, (C) HRTEM images of Pt@TiO2...
Figure 3: UV–vis diffuse reflectance spectra of the Pt@TiO2 and Pt/TiO2 samples.
Figure 4: The H2 yield from Pt@TiO2 and Pt/TiO2 for water splitting under irridiation with the given for 2 h ...
Figure 5: Schematic illustration of the photocatalytic H2 generation by ErB-sensitized Pt@TiO2 core–shell nan...
Figure 1: (a) Powder XRD pattern of cerium oxide nanospheres. (b) Wide-scan XPS survey spectrum. (c) High-res...
Figure 2: (a) UV–vis diffuse reflectance spectra of cerium oxide nanospheres (black), 7 nm CeO2 (red) nanopow...
Figure 3: (a) TEM and (b) HRTEM images of the mesoporous cerium oxide nanospheres. (c) Nitrogen adsorption–de...
Figure 4: Comparison of RhB concentrations over time at 554 nm, after photocatalytic degradation with mesopor...
Figure 5: (a) Photocatalytic degradation of RhB over time at 554 nm, in the absence of scavengers (black), an...
Figure 1: The spectrum of: (a) UV–vis absorption of V-Ti/MCM-41, and emission of (b) 200 W mercury arc lamp, ...
Figure 2: The low-angle XRD pattern of V-Ti/MCM-41.
Figure 3: The HRTEM images of V-Ti/MCM-41 photocatalyst.
Figure 4: Summary of the V K-edge characterization of V-Ti/MCM-41 with references by XANES and proposed struc...
Figure 5: Time course of the photo-epoxidation of propylene with molecular oxygen under UV–visible light irra...
Figure 6: Time course of the photo-epoxidation of propylene with molecular oxygen under artificial sunlight (...
Figure 7: The correlation between UV-light intensity (200 W mercury arc lamp) and C3H6 consumption rate and P...
Figure 8: Time course of the photo-epoxidation of propylene with molecular oxygen under UV light for C3H6 con...
Figure 9: The PO formation rate, C3H6 consumption rate and PO selectivity over V-Ti/MCM-41 versus the normali...
Figure 10: The TGA weight loss curves V-Ti/MCM-41 photocatalyst using O2 as the sweep gas: (a) fresh catalyst ...
Figure 1: XRD patterns of (a) Cd0.1Zn0.9S, (b) Ag(0.01)-doped Cd0.1Zn0.9S, (c) Ag(0.03)-doped Cd0.1Zn0.9S, an...
Figure 2: XRD patterns of (a) Cd0.1Zn0.9S, (b) Ag(0.01)-doped Cd0.1Zn0.9S, (c) Ag(0.03)-doped Cd0.1Zn0.9S, an...
Figure 3: FESEM images of (a) Cd0.1Zn0.9S, (b) Ag(0.01)-doped Cd0.1Zn0.9S, (c) Ag(0.03)-doped Cd0.1Zn0.9S (d)...
Figure 4: FESEM images of (a) Cd0.1Zn0.9S, (b) Ag(0.01)-doped Cd0.1Zn0.9S, (c) Ag(0.03)-doped Cd0.1Zn0.9S (d)...
Figure 5: DR UV–visible spectra of (a) Cd0.1Zn0.9S, (b) Ag(0.01)-doped Cd0.1Zn0.9S, (c) Ag(0.03)-doped Cd0.1Zn...
Figure 6: DR UV–visible spectra of (a) Cd0.1Zn0.9S, (b) Ag(0.01)-doped Cd0.1Zn0.9S, (c) Ag(0.03)-doped Cd0.1Zn...
Figure 7: Photocatalytic hydrogen evolution on Cd0.1Zn0.9S (filled circles), Ag(0.01)-doped Cd0.1Zn0.9S (empt...
Figure 8: DR UV–visible spectra of (a) fresh and (b) used Ag(0.01)-doped Cd0.1Zn0.9S prepared by the hydrothe...
Figure 9: Photocatalytic hydrogen evolution on Cd0.1Zn0.9S (filled circles), Ag(0.01)-doped Cd0.1Zn0.9S (empt...
Figure 1: FESEM images of as-synthesized samples (a) PZ, (b) AZ21, (c) AZ410 and (d) AZ510 showing the effect...
Figure 2: XRD patterns of as-synthesized ZnO and Ag–ZnO samples prepared with varying AgNO3 concentrations an...
Figure 3: (a) Low-magnification TEM image of ZnO nanostructures in sample PZ. (b) HRTEM image showing lattice...
Figure 4: (a) Selected area diffraction pattern from Ag–ZnO hybrid nanostructures and in the inset low magnif...
Figure 5: EFTEM images taken from the same area of a TEM image indicating the locations of different atoms ac...
Figure 6: (a) UV-visible absorption spectra of samples AZ210, AZ310, AZ410 and AZ510 with varying Ag concentr...
Figure 7: UV–visible absorption spectra showing the temporal evolution of the degradation of MB upon sun-ligh...
Figure 8: Schematic band diagram of Ag–ZnO hybrid nanostructure showing the charge redistribution processes t...
Figure 9: (a,b) Kinetics of MB photodegradation by Ag–ZnO hybrid plasmonic nanostructures with different Ag n...
Figure 1: XRD patterns of Ag2CrO4 samples prepared by different methods: (a) microemulsion, (b) precipitation...
Figure 2: SEM images of Ag2CrO4 samples obtained from different methods: (a) microemulsion, (b) precipitation...
Figure 3: TEM (a) and HRTEM (b) images of Ag2CrO4 sample prepared by microemulsion method. The inset of (b) i...
Figure 4: Nitrogen adsorption-desorption isotherms and corresponding pore size distribution curves (inset) of...
Figure 5: UV–visible diffuse reflectance spectra, the calculated band gaps (upper right inset) and the corres...
Figure 6: Band structure plots (a) and density of states (b) for Ag2CrO4.
Figure 7: Photocatalytic degradation of MB aqueous solution over Ag2CrO4 samples prepared by (a) microemulsio...
Figure 8: Cycling test of the photocatalytic degradation under visible-light irradiation of a MB aqueous solu...
Figure 9: (a) SEM image, (b) TEM image, (c) XRD pattern, and (d) UV–visible spectrum of Ag2CrO4 after five ci...
Scheme 1: Reaction scheme for the loading of GQDs onto TNAs via covalent bonding.
Figure 1: (a) TEM image of GQDs, (b) AFM image of GQDs with corresponding height profile, (c) UV–vis absorpti...
Figure 2: FESEM images of (a,b) pristine TNAs and (c,d) GQDs/TNAs; TEM images of (e) pristine TNAs and (f) GQ...
Figure 3: XRD patterns of (a) Ti foil, (b) TNAs and (c) GQDs/TNAs.
Figure 4: UV–vis absorption spectra of (a) TNAs, (b) amine-functionalized TNAs and (c) GQDs/TNAs.
Figure 5: Photodegradation of methylene blue for TNAs and GQDs/TNAs under visible light irradiation.
Figure 6: Photocurrent responses of (a) TNAs and (b) GQDs/TNAs under visible-light irradiation. The potential...
Figure 1: Schematic steps for the photocatalytic reactions occuring on the surface of a semiconductor. Adapte...
Figure 2: Schematic diagram illustrating the principle of charge transfer between CdS and TiO2.
Figure 3: Photoinduced charge separation and transport in a) TiO2 particulate film and b) TiO2 nanotube array...
Figure 4: Schematic diagrams illustrating (a) the architecture and (b) the corresponding energy diagram of do...
Figure 5: Proposed charge transfer mechanism for the visible-light-irradiated gold nanoparticle−TiO2 system. ...
Figure 6: Photoelectrochemical properties of the TiO2 NTPC and Au/TiO2 NTPC and schematic diagram of SPR char...
Figure 7: Proposed mechanisms for the carbon nanotube-mediated enhancement of photocatalysis. a) Carbon nanot...
Figure 8: Schematic drawing illustrating the mechanism of charge separation and photocatalytic process over Z...
Figure 9: Photocatalytic mechanism for TiO2–carbon nanodots under visible-light illumination. Reprinted from [112]...
Figure 10: The schematic procedures for the preparation of nitrogen-doped Ti0.91O2 nanosheets. TBA+: tetrabuty...
Scheme 1: Self-assembly of the H3[{Bi(dmso)3}4V13O40] cluster 1. An ortho-vanadate (VO43−) template allows th...
Figure 1: UV–vis spectroscopic data for the bismuth vanadium oxide cluster H3[{Bi(dmso)3}4V13O40] (1, red lin...
Figure 2: Photooxidative performance of 1 under anaerobic (blue triangles) and aerobic (red circles) conditio...
Figure 3: Photooxidative performance of 1 depending on the presence of EtOH under aerobic and anaerobic condi...
Figure 4: Quantum effiencies Φ for the homogeneous photooxidation of indigo by 1 in the visible range between...
Figure 5: Recyclability of 1 as a homogeneous indigo photooxidation catalyst under anaerobic conditions. Run ...
Figure 1: FESEM and TEM images of (a,c) CN, and (b,d) CNS samples. The inset of (b) is an enlarged FESEM imag...
Figure 2: (a) Optical absorption spectra of CN and CNS. Inset shows the Tauc plots for bandgap determination,...
Figure 3: Schematic illustration of (a) electron–hole separation at the CN/CNS heterojunction interface, (b) ...
Figure 4: (a) FESEM image of CN/CNS heterostructure, (b) XRD and (c) nitrogen adsorption–desorption isotherms...
Figure 5: TEM (a) and HRTEM (b) images of a CN/CNS heterostructure.
Figure 6: (a) Photoluminescence of CN, CNS and CN/CNS in aqueous solution. (b) Current density–voltage (J–V) ...
Figure 1: UV–vis spectra of (a) GO, (b) RGO4, (c) RGO12, (d) RGO24, and (e) RGO36 solution (20 μg mL−1). The ...
Figure 2: (A) ATR-IR spectra of GO-p, RGO4-p and RGO24-p, (B) XPS spectra of C1s for GO-p, RGO4-p and RGO24-p...
Figure 3: Chemical structure of EY.
Figure 4: Fluorescence spectra of EY-RGOx in TMA solution. The inset shows the fluorescence spectrum of EY in...
Figure 5: Transient absorption decay of 3EY* followed at 580 nm for (A) EY, (B) EY−GO, (C) EY−RGO4, and (D) E...
Figure 6: Photocatalytic H2 evolution of EY sensitized GO and RGOx. Conditions: 30 μg mL−1 GO or RGOx; 1.45 ×...
Figure 7: (A) The effect of the pH value on the photocatalytic activity of EY-RGO24/Pt. Conditions: 30 μg mL−1...
Figure 8: AQY of the EY-RGO24/Pt photocatalyst plotted as a function of the wavelength of the incident light....
Scheme 1: Schematic diagram of the reduction of GO by irradiation.
Figure 9: TEM images of GO (A), RGO24 (B), RGO24 with deposited Pt (C), and HRTEM image of deposited Pt (D). ...
Scheme 2: Proposed mechanism for the photocatalytic hydrogen evolution of a EY-RGOx/Pt system under visible l...
Figure 1: Schematic diagram of TNT-based DSSCs under back side light illumination (Inset SEM image indicates ...
Figure 2: Photocurrent–voltage characteristics of N719-DSSCs fabricated by using 3.3 μm, 11.5 μm, and 20.6 μm...
Figure 3: IPCE spectrum of the N719-DSSCs fabricated by using 3.3 μm, 11.5 μm, and 20.6 μm TNT arrays.
Figure 4: Experimental impedances of the N719-DSSCs fabricated using 3.3 μm, 11.5 μm, and 20.6 μm TNT arrays....
Figure 5: (a) A schematic diagram of charge separation driven by the electric field intensity as a function o...
Figure 6: Calculated absorption and reflectance of the DSSCs with different TNT lengths by using GTMM: (a) 3....
Figure 7: Calculated charge generation rate of the DSSCs with different TNT lengths using GTMM under 1 sun co...
Figure 1: Basic principle for overall water splitting over semiconductor photocatalysts. Reprinted with permi...
Figure 2: Illustration of mesoporous wall on the anti-photocorrosion of sulfide photocatalyst.
Figure 3: Proposed mechanism for charge transfer in Fe/Ni co-doped MCM-41. Reprinted with permission from [21]. C...
Figure 4: Proposed photocatalytic charge separation process over the band-structure controlled NiS/Cd0.5Zn0.5...
Figure 5: CdS nanoparticle enwrapped by the surrounding TNTs showed a significant enhancement of charge separ...
Figure 6: Morphological evolution of Cu2O prepared with different reaction times, (a) 30 min, (b) 60 min, (c)...
Figure 7: Enhanced light absorption ascribed to multiple light reflections in the nanosheet-based hierarchica...
Figure 8: Schematic illustration for the charge separation in CdS/mesoporous ZTP. Reprinted with permission f...
Figure 9: Photocatalytic mechanism over Ni-doped ZnIn2S4 with plenty of curved nanosheets. Reprinted with per...
Figure 10: Illustration of twin-induced 1D long range ordered homojunctions over Cd0.5Zn0.5S with alternative ...
Figure 1: ORTEP representation of the molecular structure of 1 in the crystal (hydrogen atoms are omitted for...
Figure 2: XRD pattern of Ta2O5 nanoparticles calcined at 750 °C for 4 h.
Figure 3: SEM image of Ta2O5 nanoparticles calcined at 750 °C for 4 h.
Figure 4: Size and distribution of TOPO-coated Ta2O5 nanoparticles in chloroform dispersion.
Figure 5: TEM image of the TOPO-coated Ta2O5 nanoparticles. The scale bar corresponds to 200 nm.
Figure 6: Thermogravimetry (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (...
Figure 7: Solid state diffuse reflectance UV–vis spectra of Ta2O5 nanoparticles.
Figure 8: Calculation of band gap of Ta2O5 nanoparticles by Tauc plot.
Figure 9: BET surface area plot of the calcined Ta2O5 nanoparticles.
Figure 10: Degradation of rhodamine B by UV irradiation at 0.8 mg/mL catalyst loading.
Figure 11: Effect of the concentration of Ta2O5 nanoparticles on the rate of degradation of rhodamine B.
Figure 12: Effect of dye concentration on photocatalytic degradation.
Figure 13: Effect of dye concentration on photocatalytic degradation.
Figure 14: Effect of the pH value on the rate of degradation of rhodamine B.
Figure 15: Effect of the calcination temperature on the rate of degradation of rhodamine B.
Figure 1: FTIR (a) and XPS (b) spectra of GO, G-SO3 and G-SO3 after photocatalytic hydrogen evolution
Figure 2: Raman (a) and XRD (b) spectra of GO (black), G-SO3 (red) and G-SO3 after photocatalytic hydrogen ev...
Figure 3: Photocatalytic hydrogen evolution with different graphene (a) and cobalt salts (b) at pH 10.86 in H2...
Figure 4: Photocatalytic hydrogen evolution as a function of the CoSO4 (a), G-SO3 (b), EY (c) and TEOA (d) co...
Figure 5: The TEM images nanoparticles after irradiation with (a–c) or without (d–f) G-SO3.
Figure 6: CV spectra of the 4.0 × 10−3 mol/L CoSO4 + 0.2 mol/L K2SO4 solution (black), 4.0 × 10−3 mol/L CoSO4...
Scheme 1: Schematic illustration of the photocatalytic hydrogen evolution process.