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The exfoliation of bulk C3N4 (BCN) into ultrathin layered structure is an effective strategy to boost photocatalytic efficiency by exposing interior active sites and accelerating charge separation and transportation. Herein, we report a novel nitrate anion intercalation‐decomposition (NID) strategy that is effective in peeling off BCN into few‐layer C3N4 (fl‐CN) with tailored thickness down to bi‐layer. This strategy only involves hydrothermal treatment of BCN in diluted HNO3 aqueous solution, followed by pyrolysis at various temperatures. The decomposition of the nitrate anions not only exfoliates BCN and changes the band structure, but also incorporates oxygen species onto fl‐CN, which is conducive to O2 adsorption and hence relevant chemical processes. In photocatalytic O2 reduction under visible light irradiation, the H2O2 production rate over the optimal fl‐CN‐530 catalyst is 952 μmol g−1 h−1, which is 8.8 times that over BCN. More importantly, under full arc irradiation and in the absence of hole scavenger, CH4 can be photocatalytically oxidized by on‐site formed H2O2 and active oxygen species to generate value‐added C1 oxygenates with high selectivity of 99.2 % and record‐high production rate of 1893 μmol g−1 h−1 among the metal‐free C3N4‐based photocatalysts. [ABSTRACT FROM AUTHOR]

Achieving the complete mineralization of persistent pollutants in wastewater is still a big challenge. Here, we propose an efficient photo‐self‐Fenton reaction for the degradation of different pollutants using the high‐density (Ag: 22 wt %) of atomically dispersed AgCo dual sites embedded in graphic carbon nitride (AgCo−CN). Comprehensive experimental measurements and density functional theory (DFT) calculations demonstrate that the Ag and Co dual sites in AgCo−CN play a critical role in accelerating the photoinduced charge separation and forming the self‐Fenton redox centers, respectively. The bimetallic AgCo−CN exhibited excellent photocatalytic performance toward the phenol even under extreme conditions due to an efficient degradation pathway and in situ generation of the hydrogen peroxide producing the main active oxygen species (⋅OH and 1O2) and showed long‐term activity in a self‐design photo‐Filter reactor for the purification of the phenol. Our discoveries pave the way for the design of efficient single‐atoms photocatalysts‐based photo‐self‐Fenton reaction for recalcitrant pollutant treatment. [ABSTRACT FROM AUTHOR]

Highly effective photocatalysts for the hydrogen‐evolution reaction were developed by conferring the linkers of NH2‐MIL‐125(Ti), a metal–organic framework (MOF) constructed from TiOx clusters and 2‐aminoterephthalic acid (linkers), with active copper centers. This design enables effective transfer of electrons from the linkers to the transient Cu2+/Cu+ centers, leading to 7000‐fold and 27‐fold increase of carrier density and lifetime of photogenerated charges, respectively, as well as high‐rate production of H2 under visible‐light irradiation. This work provides a novel design of a photocatalyst for hydrogen evolution using non‐noble Cu2+/Cu+ as co‐catalysts. [ABSTRACT FROM AUTHOR]

In this study, ZIF-8-modified g-C3N4 (ZIF-8/g-C3N4) composites were successfully synthesized by hydrothermal reaction. The properties of the ZIF-8/g-C3N4 composites were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (UV-vis DRS) and photoluminescence (PL) spectroscopy. The results indicated that the ZIF-8 grew on the surface of the g-C3N4, forming closely contacted interfaces between the ZIF-8 and the g-C3N4 component. The photocatalytic performance of the ZIF-8/g-C3N4 composites was evaluated through the photodegradation of Rhodamine B (RhB). The results showed that 99.8% of RhB was degraded by the ZIF-8/g-C3N4 composite with 3 wt% of ZIF-8 in 60 min under simulated sunlight, which was much higher than that of pure g-C3N4 and ZIF-8. This highly enhanced photocatalytic activity of the ZIF-8/g-C3N4 composites can be mainly attributed to strong interfacial interaction promoting the photo-generated electron–hole separation and migration. The results of radical scavenger experiments showed that ṖO2− and h+ were the dominant reactive species in the photocatalytic reaction. In addition, the ZIF-8/g-C3N4 composites showed excellent stability over several reaction cycles. Finally, a possible Z-scheme photocatalytic mechanism was proposed based on the experimental results. [ABSTRACT FROM AUTHOR]

Abstract: Hierarchical photocatalytic composite BiOBr@graphene oxide@melamine foam was developed by using a solvothermal process. In this composite, the graphene oxide‐wrapped melamine foam acted as the substrate for supporting the catalyst, and the BiOBr nanosheets stably combined with the graphene oxide surface in a uniform distribution. This composite could be floated on the solution surface to inhibit the light shielding effect of colorful organic pollutants. Furthermore, the graphene oxide‐wrapped melamine foam provided mass transfer channels for organics and enriched the organics in its 3D structure. BiOBr nanosheets presented efficient photodegradation of organics and solved the problem of adsorption saturation of graphene oxide@melamine foam. Graphene oxide could further improve the light utilization, inhibit the recombination of charges, and enrich the organics. In view of the synergistic effect of adsorption and photocatalysis, this catalyst system realized the efficient removal of the organic rhodamine B and presented the promoted amount of contaminant removal with increased rhodamine B concentration. [ABSTRACT FROM AUTHOR]

A new type of ZIF-67/ZnO hybrid coated on Co foil was prepared via an electrochemical etching and hydrothermal processes for photoelectrocatalytic sterilization. The thorn-like ZnO nanorods in the photoanode films play an important role of capturing bacteria from solution. The porous ZIF-67 with high specific surface area efficiently adsorbed the leaked K+ ions assisted by the hERG release, and realizes the visible-light photocatalytic activity with the generation of charge carriers. The visible-light photoelectrocatalytic antibacterial effect on ZIF-67/ZnO hybrid is further promoted by applying a potential to the photoelectrode to promote the separation and transfer of charge carriers. As a result, the visible-light photoelectrocatalytic antibacterial effect was powerful for rapid destroy of cell integrity. At the same time, the decomposition of bacteria cell was also facilitated to further accelerate the K+ leakage. Thus, the simultaneous process of destroying cell membrane integrity and leaking K+ ions is achieved during the photoelectrocatalytic process, leading to the complete destruction of bacteria. This photoelectrocatalytic antibacterial system based on ZIF-67/ZnO@Co foil offers a potential way for sterilization application in the future. [Display omitted] • ZIF-67/ZnO@Co foil acted as photoanode for photoelectrocatalytic sterilization. • Destroy of cell integrity and leakage of K+ ions were simultaneously achieved. • E. coli bacteria was anchored and captured by thorn-like ZnO nanorods. • ZIF-67 realized visible-light photocatalytic inactivation via charge carriers. • ZIF-67 induced efficient K+ adsorption assisted by release of K+ channel protein. [ABSTRACT FROM AUTHOR]

Mesoporous titanium nitride (TiN) microspheres with tunable chamber structures were synthesized through NH3 nitridation of organotitania obtained via solvothermal alcoholysis. Owing to high content of organic species in organotitania, which stabilized the original structure and also promoted the nitridation at low temperature, TiN duplicated the solid, yolk-shell, and hollow chambers of organotitania in NH3 nitridation and also formed the mesoporous structure after removing organic species. During visible light-induced photocatalytic water splitting, the yolk-shell TiN demonstrated a higher H2 evolution efficiency than the solid, hollow, and crushed TiN; the yolk-shell TiN obtained through N2 nitridation; and other semiconductor photocatalysts reported so far without the aid of noble metals. This could be attributed mainly to the narrow energy band gap for absorbing visible light, high surface area, and excellent electrical conductivity, which facilitated light harvesting, reactant adsorption, and photoelectron-hole separation to suppress their recombination. Moreover, it could be easily recycled and thus used repetitively. [ABSTRACT FROM AUTHOR]

A novel bifuntional RuO 2 @TiO 2 @Pt photocatalyst was designed by control-assembling TiO 2 hollow spheres with RuO 2 and Pt deposited onto outer and inner shell surfaces, respectively. This RuO 2 @TiO 2 @Pt was used in coupled photocatalytic H 2 production and organic pollutant degradation, which showed the synergetic effect between photocatalytic oxidation and reduction. Meanwhile, the RuO 2 facilitated the transfer and collection of photo-induced holes generated from TiO 2 , followed by oxidizing organic pollutants for degradation. Similarly, the Pt promoted the transfer and enrichment of photoelectrons, which favored the proton reduction to H 2 as a cocatalyst. Thus, the RuO 2 @TiO 2 @Pt exhibited very high activity owing to the enhanced light harvesting through multiple reflections in the TiO 2 hollow chamber, the rapid separation corresponding to the low recombination of photoelectron-hole and the cooperative promoting effect from RuO 2 and Pt cocatalysts in photocatalytic oxidation and reduction. [ABSTRACT FROM AUTHOR]

The compound Bi 7 O 9 I 3 has been considered as a promising candidate for organic dye degradation in wastewater, but it has relatively low photocatalytic activity and difficulties in the recycling processes. In this work, a novel floating 3D porous Bi 7 O 9 I 3 /N-doped graphene aerogel (Bi 7 O 9 I 3 /NGA) composite was successfully synthesized through a facile hydrothermal route. The Bi 7 O 9 I 3 /NGA composite exhibited highly enhanced photocatalytic performance toward degrading rhodamine B under visible-light irradiation, which increased 6.0 and 2.3 times compared with the Bi 7 O 9 I 3 and Bi 7 O 9 I 3 /GA, respectively. The enhancement of photocatalytic degradation activity could be ascribed to the extensively promoted charge generation and migration efficiency, visible light utilization ability and reactive oxygen species production. Besides, the special 3D macroscopic block structure of Bi 7 O 9 I 3 /NGA allowed it to float, making it easy to recycle. The photocatalytic degradation efficiency of Bi 7 O 9 I 3 /NGA composite still could reach up to 92.7% after four consecutive cycles and presented satisfactory stability and reusability. Moreover, a possible photocatalytic degradation mechanism was revealed by radical species trapping and semi-quantitative analyses experiments. [ABSTRACT FROM AUTHOR]

A mesocrystal ZnCo 2 O 4 on reduced graphene oxide (rGO) nano-composite was successfully synthesized by a low-temperature annealing of bimetal organic frameworks on rGO. In this nano-composite, rGO nanosheets worked as the two-dimensional support to significantly improve the dispersity and conductivity of nano-composites. The mesoporous ZnCo 2 O 4 crystal derived from ZnCo-ZIF worked as the main active sites with the optimized Zn/Co ratio to ensure an ideal valence band structure as well as enhanced visible-light harvesting properties. The as-prepared rGO@ZnCo 2 O 4 nano-composites showed a remarkable activity in visible-light photocatalytic NO oxidation with the conversion of 83.8% under visible light and 92.6% under simulated solar light. It also exhibited a higher stability than that of N-doped TiO 2 , thereby making this nano-composite as a promising and stable photocatalyst for environmental remediation. [ABSTRACT FROM AUTHOR]

The hybrid Ag/TiO 2 -N photocatalyst was prepared via a supercritical solvothermal process in ethanol fluid. The simultaneous achievement of reduction of Ag + ions and N-doping in silver-ammonia complex solution led to the uniform distribution of Ag nanoparticles stably combined with the surface of TiO 2 -N substrate. As a result, the visible-light photocatalytic inactivation of Acinetobacter baumannii was facilitated via the enhanced visible light harvesting and the high separation efficiency of photo-induced charge carriers. By means of the main active species of   O 2 − radical, the synergistic effect of Ag nanoparticles and TiO 2 -N could induce the structure change of bacteria with the leakage of K + ions as well as the mineralization of cell membrane with the elimination of self-repair function, leading to the final cell death. In comparison, the bactericidal activity of Ag nanoparticles and TiO 2 -N under UV light irradiation was due to the intrinsic efficiency and the high light harvesting, respectively. The photothermal effect of Ag nanoparticles in the near-IR light region could be possibly remained by TiO 2 -N substrate to achieve the antibacterial activity. Furthermore, Ag/TiO 2 -N photocatalyst played great bactericidal effect for kinds of bacteria, implying the applicable future to the medical disinfection. [ABSTRACT FROM AUTHOR]

A solar-light double illumination photoelectrocatalytic cell (SLDIPEC) was fabricated for autonomous CO 2 reduction and O 2 evolution with the aid of photosystem II (PS-II, an efficient light-driven water-oxidized enzyme from nature) and utilized in a photoanode solution. The proposed SLPEC system was composed of Cu foam as the photoanode and p-Si nanowires (Si-NW) as the photocathode. Under solar irradiation, it exhibited a super-photoelectrocatalytic performance for CO 2 conversion to methanol, with a high evolution rate (41.94 mmol/hr), owing to fast electron transfer from PS-II to Cu foam. Electrons were subsequently trapped by Si-NW through an external circuit via bias voltage (0.5 V), and a suitable conduction band potential of Si (− 0.6 eV) allowed CO 2 to be easily reduced to CH 3 OH at the photocathode. The constructed Z-scheme between Cu foam and Si-NW can allow the SLDIPEC system to reduce CO 2 (8.03 mmol/hr) in the absence of bias voltage. This approach makes full use of the energy band mismatch of the photoanode and photocathode to design a highly efficient device for solving environmental issues and producing clean energy. [ABSTRACT FROM AUTHOR]

A multifunctional C/N-ZnO/Bi 2 WO 6 Z-scheme heterojunction was fabricated by ZIF-8 derived C/N-ZnO and Bi 2 WO 6 for improving the visible light absorption performance and accelerating the carriers transfer due to the doping of C/N and addition of residual C species. [Display omitted] • C/N-doped ZnO with residual C species was developed by regulated pyrolysis of ZIF-8. • The bandgap of ZnO was regulated by doping C/N. • Coordination adsorption between Zn2+ and antibiotic accelerate removal of pollutants. • Constructing a Z-scheme heterojunction by residual C as an electron transfer medium. A multifunctional Z-scheme C/N-ZnO/Bi 2 WO 6 (CZB) photocatalyst was fabricated by ZIF-8 derived C/N-ZnO and Bi 2 WO 6 via a regulated pyrolysis. The obtained photocatalysts were characterized and the photocatalytic activity was investigated by degrading antibiotics. Especially, the composite with 5% mass ratio of C/N-ZnO (5-CZB) exhibited the best photocatalytic activity for tetracycline, enrofloxacin and norfloxacin under visible light irradiation and degradation efficiency was 4.48, 2.43 and 2.79 times higher than pure Bi 2 WO 6 , respectively. That was mainly due to the doping of C/N in ZnO structure from the pyrolysis of ZIF-8 regulated the band gap and improved the photoresponse ability. Meanwhile, the residual C species as an electron transfer medium were conducive to constructing Z-scheme heterojunction between ZnO and Bi 2 WO 6. The synergistic effect leaded to the extension of light response range and acceleration of the carriers transfer. The tests showed that •O 2 – and h+ were the dominant active species to decomposed antibiotic molecules. Additionally, coordination adsorption between Zn2+ in CZB composites and antibiotic molecules is beneficial to removal the pollutants, which provides an interesting approach for designing photocatalysts. [ABSTRACT FROM AUTHOR]

Highlights: [•] Au quantum dots enhanced rutile TiO2 was obtained. [•] Photocatalytic NO pollutant removal at room temperature was studied. [•] Cooperative promoting effects form Au and TiO2 were studied. [•] Significantly enhanced photocatalytic activity was obtained. [Copyright &y& Elsevier]

Abstract: Bi2MoO6 hollow microspheres with cage-like pores on the outer shell were synthesized by aerosol-spraying with glucose as a template. The aerosol-spraying temperature and the amount of glucose played key roles in determining the crystal phase and the Bi2MoO6 morphology including outer shell thickness and number of cage-like pores on the outer shell. The photocatalytic degradation of rhodamine B under visible-light irradiation was examined which revealed that the reaction followed first order kinetics with respect of rhodamine B concentration and rhodamine B was completely degraded into CO2 via de-ethylation process with the formation of 5 intermediates. The as-prepared Bi2MoO6 exhibited high activity owing to the high surface area and additionally because of multiple light reflections in the hollow chamber. [Copyright &y& Elsevier]

C@Fe 2 C/TiO photocatalytic CO 2 realizes C–C coupling to produce C2 fuel mainly due to the formation of a Z-scheme heterojunction between Fe 2 C and TiO, which changes the electron transmission path, and the CO* generated by TiO induces the production of C2. [Display omitted] • A novel C@Fe 2 C/TiO ternary composite catalyst is prepared. • The catalyst exhibits high activity under simulated sunlight with main-product of C 2 H 4. • The catalyst could be excited by NIR lights. CO 2 conversion is of great industrial importance in reducing green-house effect and reusing carbon-resource. Most studies are focused on the thermocataltic CO 2 conversion, which usually performs over noble metal catalysts at high temperature and pressure. Recently, photocatalytic CO 2 conversion has caused increasing attention owing to the energy save, low-cost and clean reaction route. The key problem is to design photocatalysts high activity and strong durability. Here, we choose to prepare a novel C@Fe 2 C/TiO ternary composite catalyst by reducing organic compounds under an ammonia atmosphere. During CO 2 reduction reaction in aqueous solution, the catalyst exhibits high activity under simulated sunlight with main-product of C 2 H 4 (35.483 μmol g-1h−1). Even irradiating with near-infrared lights, the catalytic conversion still proceeds successfully, but the main-product turns to be CH 4 (18.315 μmol g-1h−1). Based on the chanracterizations and DFT calculation, the high activity could be attributed to the cooperation between the Fe 2 C catalyst toward C 2 H 4 and the TiO 2 photocatalyst. Specially, C@Fe 2 C/TiO could be excited by NIR lights owing to the narrow-energy band gap. More importantly, the photoelectrons could be easily separated from holes owing to the presence of the Z-scheme heterojunctions, leading to the enhanced photocatalytic activity. This work provides new insights to understand the CO 2 reduction reaction mechanism to develop photocatalysts. [ABSTRACT FROM AUTHOR]

• A ternary bridge chain W 2 N/C/TiO photocatalyst realizes NIR light driven water splitting. • The production of hydrogen and oxygen is achieved without the the sacrificial reagent. • The AQE for W 2 N/C/TiO for NIR light water splitting can reach as high as 2.14%. Photocatalysts that can not only harvest broader solar irradiation (from UV to near infrared (NIR) light region) but also achieve higher solar-to-hydrogen conversion efficiency are critical for solar hydrogen economy. In this research, we report a ternary bridge chain W 2 N/C/TiO photocatalyst for the first time to realize an efficient and stable visible and NIR light driven water splitting. This photocatalyst can realize overall water splitting using bifunctional mechanism with hydrogen (H 2) generation part and oxygen (O 2) generation part. The optimal H 2 and O 2 generation rates based on the W 2 N/C/TiO photocatalyst are 2.01 and 1.11 μmol g-1h−1 under the irradiation of NIR light (λ > 700 nm). In this new photocatalyst, W 2 N and TiO were integrated into nanosized carbon fibers that serve as H 2 and O 2 evolution active sites. And the hydrogen apparent quantum efficiency (AQE) for W 2 N/C/TiO composite photocatalyst for NIR light water splitting can reach as high as 2.14% at 700 ± 15 nm. This research indicates that W 2 N/C/TiO photocatalyst can be effective under broaden (Ultraviolet, Visible and Near-Infrared) light. Combining interfacial and electrochemical characterizations, we have found that W 2 N/C/TiO photocatalyst can efficiently separate charges through the interfaces between C/W 2 N and C/TiO and harvest low energy photons in NIR region. Because of the bridge chain structure among W 2 N, C, and TiO electron transfer from W 2 N to TiO via C can promote charge separation and impede the recombination of photo-generated electron and hole pairs. It is therefore that this bridge chain structured W 2 N/C/TiO nanofiber photocatalyst can be a promising material for overall water splitting due to the capacity to utilize a broader solar spectrum. [ABSTRACT FROM AUTHOR]