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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]

Novel TiO2 nanosheets co-modified with MoS2 quantum dots (MQDs) and N-doped carbon dots (NCDs), designated MQDs/NCDs/TiO2, were synthesized through a simple and mild process. The MQDs/NCDs/TiO2 nanocomposites exhibited significantly improved efficiency in the photocatalytic degradation of RhB compared to pure TiO2, mainly attributed to the synergy of excellent photoconversion by NCDs and efficient separation and transfer of photogenerated electron–hole pairs induced by the two heterojunctions formed in MQDs/NCDs/TiO2. More interestingly, the degradation rate was further promoted by 2.15 times after adding 2 mmol persulfate to the MQDs/NCDs/TiO2 photocatalytic system. This result is due to the excellent collaboration between the photocatalysis and persulfate activation, in which the persulfate was effectively activated by photogenerated electrons to generate abundant sulfate radicals (SO4˙−) and hydroxyl radicals (˙OH); meanwhile, the electron consumption caused by the persulfate effectually restrained surface electron–hole recombination, inducing more holes (h+) to participate in pollutant degradation. Radical quenching experiments and electron spin resonance spectra show that SO4˙−, ˙OH, ˙O2− and h+ were all in charge of RhB elimination in the MQDs/NCDs/TiO2–PS system. This work may provide guidance for employing dual quantum dots as co-catalysts, cooperating with activated persulfate, to enhance photocatalytic performance in contaminant degradation. [ABSTRACT FROM AUTHOR]

In this work, a novel ternary Ag@Ag2O/BiOCl Z-scheme photocatalyst driven by visible light was successfully fabricated through a simple two-step route in which the Ag@Ag2O cocatalyst was decorated on {001} crystal facets of BiOCl nanosheets. As controls, BiOCl nanosheet, Ag2O nanoparticle and Ag/BiOCl composite were also synthesized by the appropriate means. The as-synthetized samples were investigated by various characterization methods. Compared with the pristine BiOCl, Ag2O and Ag/BiOCl counterparts, the Ag@Ag2O/BiOCl composite exhibited a superior performance towards RhB degradation with an efficiency of 91.2% within 120 min under visible light illumination of which the reaction rate is about 32, 3 and 5 times as much as pristine BiOCl, Ag2O and Ag/BiOCl samples, respectively. The enhanced performance for RhB degradation may be ascribed to a possible Z-scheme junction, which is advantageous to effectively boost interfacial charge transport and depress the photoinduced carrier recombination. The detailed Z-scheme mechanism towards RhB degradation of the Ag@Ag2O/BiOCl composite was also further explored and discussed. [ABSTRACT FROM AUTHOR]

Highlights from the article: Photocatalysis: Microwave-Induced Metal Dissolution Synthesis of Core-Shell Copper Nanowires/ZnS for Visible Light Photocatalytic H2 Evolution (Adv. Keywords: copper nanowires; H2 evolution; microwave synthesis; photocatalysis Copper nanowires, H2 evolution, microwave synthesis, photocatalysis.

A microwave‐induced metal dissolution strategy is developed for in situ synthesis of copper nanowires/ZnS (CuNWs/ZnS) hybrids with core–shell structure. The CuNWs are used as microwave antennas to create local "super‐hot" surfaces to further initiate ZnS crystallization with full coverage on CuNWs. With the help of S2−, the hot metal surface further results in the CuNWs dissolution with promoted Cu+ diffusion and incorporation into the ZnS lattice. With the narrowed bandgap of ZnS and the strongly coupled interface between CuNWs and ZnS created by microwaves, the as‐prepared hybrid composites exhibit an enhanced activity and stability in visible light for the photocatalytic H2 evolution. The corresponding H2 evolution rate reaches up to 10722 µmol h−1 g−1 with apparent quantum efficiency (AQE) of 69% under 420 nm LED irradiation, showing a remarkably high AQE among the noble‐metal free visible light‐driven photocatalysts and demonstrating a promising potential in practical applications to deal with the energy crisis. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) is one of the major pollutants in the air and the removal of dilute NO still faces challenges of low efficiency. Herein, an electron-withdraw groups functionalized metal-organic frameworks (MOFs) was reported as photocatalyst for the efficient removal of NO. The UiO-66 was conferred with nitro groups (-NO 2), showing narrow band gap due to the conjugate with the electron cloud on the benzene ring, leading to deep color of this photocatalyst and high visible light sensitivity. Meanwhile, the electron acceptor -NO 2 greatly increased the adsorption toward electron donor NO molecules. Resultingly, a high NO (550 ppb) removal rate of 83% and 76% were achieved under visible-light irradiation (λ > 400 nm) under dry and moist condition, respectively. This work provides a new strategy for the regulation of MOFs based photocatalysts, which may be applied in the treatment of air pollutants such as NO removal. [Display omitted] • A visible-light-driven Nitro-Functionalized-MOF photocatalyst catalyst was developed. • Electron-withdraw nitro modification highly expanded the visible light adsorption. • The adsorption towards NO was enhanced. • High NO removal rate is achieved at without the accumulation of NO 2. [ABSTRACT FROM AUTHOR]

• Stable, carrier separation tailorable N -CMPs photocatalysts. • Tailorable physicochemical and optoelectronic properties at molecular-level. • The monomers' polarity determining the polymer's photocatalytic reactivity. • High AQY (6.4% at 420 nm) among the newfangled polymer photocatalysts. The molecular design of highly photo-functional polymers with high charge separation efficiency and wide spectral absorption are long term quest for photocatalysis. Herein, we design and develop a series of nitrogen-containing conjugated microporous polymers (N -CMPs) with tailored donor-acceptor units for enhancing charge separation and light harvesting for visible light photocatalytic H 2 production. By alternating the substitution position (o-, m-, or p-) and the number of electron donor (carbazole, diphenylamine) and acceptor (cyano) units on the 3D-core structure, a series of N -CMPs with adjustable donor-acceptor (D-A) charge separation efficiencies and tuneable band gaps in the range of 1.64–2.29 eV were obtained, enabling the precise control of the photocatalytic activity at the molecular level. The optimized N -CMP (4-CzPN) exhibits a higher visible light H 2 production rate at 2103.2 μmol/h·g and the apparent quantum yield (AQY) at 420 nm reaches 6.4%. Furthermore, the 4-CzPN photocatalyst maintains excellent durability and recycling performance under 25 h continued light irradiation. The outstanding photocatalytic performance of the optimized N -CMPs with D -A structure is attributed to the enhanced polarity and conjugated degree of their core structure, which promotes charge separation and light absorption. [ABSTRACT FROM AUTHOR]

A Fenton-like catalyst comprising of hydrophilic mesoporous carbon (HMC) and ferric ions was found very efficiently in degradation organic pollutants under visible light irradiation in the presence of H 2 O 2 . HMC with graphene domains and plenty of oxygen containing groups such as carboxyl groups can cooperate with ferric ions to form a visible light active Fe(III)-HMC configuration. Fe(III)-HMC showed obviously enhanced phenol degradation and mineralization efficiencies than that in dark condition. Acidic condition (pH = 3) is not only more superior in phenol degradation but also in iron leaching in comparison with the case at basic conditions (pH = 4.5–7.0) for Fe(III)-HMC. Total organic carbon (TOC) removal efficiency of five typical organic pollutants show that visible light active Fe(III)-HMC catalyst is more efficient than homogeneous Fenton reagents FeSO 4 /H 2 O 2 excluding the temperature effect. Electron spin resonance (ESR) and electrochemical measurements reveal that the presence of active phenoxyl radicals and ligand to metal charge transfer (LMCT) facilitates the cycling of Fe(III)/Fe(II) and inhibit the side reaction via Haber-Weiss reaction. ·OH radicals rather than O 2− and OOH were proved as the predominantly active oxidant. The proposed Fe(III)-HMC configuration activated by visible light opens up a new strategy for carbon based materials and iron species in Fenton-like chemistry. [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]

Highlights: [•] 3DOM Bi2O3/TiO2 film was prepared by sol–gel method with PS microspheres. [•] Bi2O3-TiO2 heterojunctions realized the low photoelectron-hole recombination. [•] 3DOM structure promoted light-harvesting and facilitated reactant adsorption. [•] Rotating disk reduced light shielding on Bi2O3-TiO2 film in color solution. [•] Visible-light single- and mixed-dyes degradation or Cr6+ reduction was enhanced. [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]

Highlights: [•] A hierarchical BiOCl film was synthesized using a facile way from Bi2O3 film. [•] The growth mechanism was analyzed by FESEM at different reaction time. [•] High UV activity was exhibited on RB removal due to semiconductor photoexitation. [•] It also possessed superior visible light activity for RB sensitization degradation. [•] The photocatalytic mechanisms were investigated under UV and visible light. [Copyright &y& Elsevier]

1T and 2H mixed phase MoS 2 nanobelts was deposited on Ti3+ self-doped TiO 2 nanosheets which exhibits excellent photodegradation performance. [Display omitted] • The 1T-2H MoS 2 /TiO 2−x composite exhibits enhanced photocatalytic degradation activity. • The Ti3+ and oxygen vacancy defects enhance the visible light adsorption of TiO 2. • The heterojunction structure improves the efficiency of charge transfer and separation. • The metalitic 1T phase MoS 2 accelerates charge transfer between 2H MoS 2 and TiO 2−x. A novel 1T-2H MoS 2 /TiO 2−x composite was fabricated via a facial hydrothermal and in-situ chemical reduction process, in which 1T and 2H mixed phase MoS 2 (1T-2H MoS 2) nanobelts were deposited on Ti3+ self-doped TiO 2 (TiO 2−x) nanosheets. This 2D-2D 1T-2H MoS 2 /TiO 2−x composite exhibits excellent photocatalytic degradation performance toward RhB under visible light, which is much higher than that of pristine TiO 2. The remarkably enhanced photocatalytic activity of 1T-2H MoS 2 /TiO 2−x composite can be ascribed to the 2D heterostructure, Ti3+ and oxygen vacancy defects, which enhances the adsorption for pollutants, provides abundant reaction active sites, extends the photoresponse to visible light region, benefits the effective charge separation and transport. Furthermore, the experiment results showed that the metallic 1T phase MoS 2 in 1T-2H MoS 2 /TiO 2−x composite could effectively accelerate charge transfer between 2H phase MoS 2 and TiO 2−x , resulting in enhanced photocatalytic degradation ability. Moreover, a feasible photocatalytic reaction mechanism of 1T-2H MoS 2 /TiO 2−x photocatalytic system was proposed in view of the active species trapping experiments, electron spin resonance tests and energy band analysis. [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]