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• The g-C 3 N 4 /7Ag/m-CeO 2 composite photocatalyst was successfully synthesized. • The introduction of g-C 3 N 4 nanosheets alleviated the photocorrosion of Ag. • The g-C 3 N 4 /7Ag/m-CeO 2 exhibits higher activity for CO 2 photoconversion. In this work, the ordered mesoporous CeO 2 (m-CeO 2) was successfully fabricated via the nanocasting pathway, through using SBA-15 as a hard template. Besides, g-C 3 N 4 /Ag/m-CeO 2 composite was successfully constructed by calcination method. Meanwhile, the obtained samples were investigated by series of test techniques. The XRD, SEM and TEM results show that the m-CeO 2 and Ag/m-CeO 2 with the ordered mesoporous trait. Besides, the EPR, Raman and XPS results suggest that the oxygen vacancies (O v) and Ce3+ and Ce4+ are in g-C 3 N 4 /Ag/m-CeO 2. In addition, the ordered mesostructure is favorable for the CO 2 molecular movement and adsorption/desorption reaction. The g-C 3 N 4 nanosheets, a promising material possessing suitable conductor band, large specific area, non-toxicity, and outstanding chemical stability, is a candidate semiconductor for CO 2 conversion. The introduction of g-C 3 N 4 nanosheets to Ag/m-CeO 2 overcomes the photocorrosion of Ag nanoparticles and Ag facilitate the transfer of photogenerated electrons. The photocatalytic activity results show that when the loading of Ag is 7 wt%, the g-C 3 N 4 /7Ag/m-CeO 2 composite exhibits the superiority activity for CO 2 photoconversion to CO (13.94 μmol/g) and CH 4 (7.39 μmol/g) under UV-irradiation in 10 h. [ABSTRACT FROM AUTHOR]

Depression is a refractory psychiatric disorder closely associated with dysfunction of the gap junctions (GJs) between astrocytes as well as neuroinflammation. Higenamine (Hig) is a potent cardiotonic ingredient in Fuzi (i.e., Aconitum carmichaeli Debx.) with anti-inflammatory and antioxidant effects, which has a significant protective effect on damaged nerve cells and has great potential for the treatment of neuropsychiatric diseases. Rats were stimulated by chronic unpredictable stress (CUS) for 28 days while given Hig (5, 10, 20 mg/kg) and then analyzed behaviorally by the open field test, sucrose preference test, and forced swimming test. Changes in astrocyte GJs function and morphology were observed by dye transfer and transmission electron microscopy, respectively. Expression and phosphorylation of connexin 43 (Cx43) were analyzed by Western blot. Also, considering the close relationship between depression and neuroinflammation, we determined the inflammatory response in serum with ELISA kits and analyzed the expression of inflammation-related proteins with Western blot. Hig ameliorated CUS-induced depression-like behavior in rats. Hig administration improved gap junctional dysfunction in astrocytes, reduced gap junctional gaps and elevated the expression of Cx43 and decreased the phosphorylation of Cx43. Meanwhile, Hig administration was also able to attenuate the inflammatory response that occurs after CUS in rats. For the role of Cx43 in depression, we did not validate it more deeply in animal models with knockout Cx43. In addition, GJs dysfunction might be associated with the inflammatory response seen in depression, but this needs to be further investigated. Hig ameliorates depression and exerts its antidepressant effect possibly by improving the dysfunctional GJs between astrocytes and the inflammatory response. [Display omitted] • Hig ameliorates CUS-induced depression-like behavior in rats. • Hig increases Cx43 expression and inhibits Cx43 phosphorylation in depressed rats. • Hig plays an antidepressant role by improving the gap junction function between astrocytes. • Hig was able to reduce the inflammatory response seen in depressed rats. [ABSTRACT FROM AUTHOR]

2D/2D heterojunction photocatalyst of CdIn 2 S 4 on nitrogen doped reduced graphene (N-rGO) was fabricated by in situ hydrothermal method. It is noticeable that the flower-like CdIn 2 S 4 photocatalyst composed of film is controlled by the temperature of synthesis process. When CdIn 2 S 4 photocatalyst load on N-rGO, irregular film N-rGO functions as support to disperse the CdIn 2 S 4 , forming the 2D/2D interfacial structure, which is confirmed by SEM, TEM and HRTEM. When the mass fraction of N-rGO is 10%, the binary composite photocatalyst could photodegrade 80% 50 mg/L 2,4-dichlorophenol (2,4-DCP). That is because the heterojunction formed between CdIn 2 S 4 and N-rGO promotes the electron transfer, especially the interfacial contact region. What's more, the N-rGO can efficiently accumulate the 2,4-DCP molecules because of its unique structure, bettering the contact rate between 2,4-DCP and the whole photocatalyst. The possible mechanism of photodegrading 2,4-DCP was discussed and investigated. This work highlights the synergistic effect, especially the harmony between charge transfer and active sites to benefit the photocatalytic performance. A schematic of possible photocatalytic mechanism. Image 1 • 2D/2D CdIn 2 S 4 /N-rGO interfacial heterojunction photocatalyst was obtained by in situ hydrothermal method. • The as-prepared 2D/2D CdIn 2 S 4 /N-rGO materials exhibited extensively enhanced photocatalytic activity for the degradation of 2,4-DCP under visible light irradiation. • The possible process about irregular and looser CdIn 2 S 4 nanosheets formed was given. • Intimate 2D interfacial heterojunction gives more channels to transfer photogenerated carries and N-rGO supplies active sites, bettering photocatalytic performance. A possible mechanism of 2D/2D CdIn 2 S 4 /N-rGO photocatalyst for the enhancement of visible light performance was proposed. [ABSTRACT FROM AUTHOR]

S-scheme heterojunction of In 2 O 3 /H 1.5 CN/2Au was prepared by hydrothermal, acidizing and calcination methods. The two-dimensional thin layer H 1.5 CN avoided the aggregation of In 2 O 3 and completed the S-scheme charge transfer with In 2 O 3. Moreover, Au not only enhanced the visible light absorption capacity of composites but also provided more active sites for CO 2 reduction. [Display omitted] • S-scheme heterojunction of In 2 O 3 /H 1.5 CN/2Au achieve CO 2 photocatalytic conversion to CO and CH 4. • The enhanced photocatalytic activity results from effective interfacial charge migration and separation and increased active sites. • The LSPR effect of Au improves the utilization of visible light. The construction of S-scheme heterojunction is of great significance for the photocatalytic reduction of CO 2. Here, we prepared two-dimensional (2D) ultra-thin g-C 3 N 4 by acidifying the carbon nitride precursor, and used In 2 O 3 to construct a S-scheme heterojunction with 2D g-C 3 N 4 , and finally In 2 O 3 /H 1.5 CN was modified with Au nanoparticles. The physicochemical properties of the prepared materials were studied by SEM/TEM, XPS, DRS, PL and photochemical test. Meantime, the S-scheme charge transfer mechanism was demonstrated by UPS and ESR. As a result, on the one hand, S-scheme heterojunction accelerated the transfer of electrons on the CB of In 2 O 3 to the VB of g-C 3 N 4 , avoided the recombination of photon-generated carrier. On the other hand, Au, as an effective cocatalyst, promoted photoinduced electron transfer and provided more active sites for CO 2 reduction and the local surface plasmon resonance phenomenon caused by Au NPs enhanced the visible light absorption capacity of the composite material. Moreover, 2D thin layer of g-C 3 N 4 played a carrier effect to disperse In 2 O 3 cube. Therefore, In 2 O 3 /H 1.5 CN/2Au had stable CO 2 reduction products, and the yields of CO/CH 4 reached 141.24/77.05 μmol/g. [ABSTRACT FROM AUTHOR]

rGO modified g-C 3 N 4 /R-CeO 2 Multi-interface contact S-scheme heterojunction photocatalyst maximizes the transfer efficiency of photogenerated electron and the CO 2 adsorption ability, thus greatly improving the CO 2 photoreduction performance. [Display omitted] • 2D-1D-2D g-C 3 N 4 /R-CeO 2 /rGO photocatalyst has been prepared for CO 2 photoreduction. • 2D-1D-2D multi-interface contact structure is of help for carrier transfer process. • π-π conjugation effect and Ce4+/Ce3+ transformation facilitate electron transmission. • In-situ FTIR and 13C isotope tracer tests analysis the CO 2 photoreduction mechanism. Construction of multi-interface contact step-scheme (S-scheme) photocatalyst is a promising pathway to achieve high-electron transfer efficiency for photocatalytic CO 2 reduction. In this paper, g-C 3 N 4 nanosheets were selected as the main photocatalyst, rod-like CeO 2 (R-CeO 2) with unique Ce4+→Ce3+ conversion property and rGO were loaded on the g-C 3 N 4 surface to construct 2D-1D-2D sandwich photocatalyst. The yields of CO and CH 4 were about 63.18 and 32.67 μmol/g after 4 h when the rGO/R-CeO 2 /g-C 3 N 4 was used as catalyst, which were about 4 and 6 times higher than that of pure CN, respectively. Cyclic experiments proved that the composite had excellent photocatalytic and material stability. Photoelectrochemical tests showed that the construction of S-scheme electron transfer model and the introduction of rGO can great enhance the electron transmission and separation of photogenerated electron-hole pairs. CO 2 adsorption test identified that the loading of R-CeO 2 and rGO obviously enhanced the CO 2 adsorption ability of pure g-C 3 N 4. Density functional theory (DFT) calculations used to analyze the electron transfer path and the formation of the build-in electric field at the semiconductor interface. In-situ FTIR and 13CO 2 element-tracer detection carried out to research the process of CO 2 photoreduction. A possible multi-interface contact S-scheme electron transfer mechanism for enhanced CO 2 photoreduction activity has been discussed. [ABSTRACT FROM AUTHOR]

• LSPR effect enhanced Z-scheme ZnO/Au/g-C 3 N 4 micro needles film (3-ZAC) has been prepared for the photoreduction of CO 2 into CO under UV–vis light irradiation. • Au NPs at the interface of ZnO/g-C 3 N 4 not only act as the electron-transfer bridge, but also as LSPR excited source to speed up the separation of electron-hole pairs photogenerated in the semiconductors. • DFT calculation and FDTD simulation methods has been used to prove the transfer processes of photogenerated electron. The photoproduction of CO from the photocatalytic CO 2 reduction process has been evidenced from 13C isotope tracer tests. • This work demonstrates the importance of the build-in electric field formed at g-C 3 N 4 /ZnO interface and local electromagnetic field of Au NPs for the photoreduction process, providing an inspiring concept for future advancement in this area. Local Surface Plasma Resonance (LSPR) effect enhanced Z-scheme ZnO/Au/g-C 3 N 4 micro-needles film (3-ZAC) has been prepared for the photoreduction of CO 2 into CO under UV–vis light irradiation. Photoreduction experiments show that 3-ZAC has the excellent photocatalytic performance and reusability. The CO production can be achieved 689.7 μmol/m2 after 8 h reaction time, which is 4.5 higher than that of the pure ZnO film. 13C isotope test shows that CO is produced from CO 2 by photoreduction. DFT calculations confirm that build-in electric field formed at g-C 3 N 4 /ZnO interface effectively promoted the electron transfer efficiency in Z-scheme interface. FDTD simulations prove that Au NPs not only act as electron-transfer bridge, but also as LSPR excited source to speed up the separation of electron-hole pairs. In-situ FTIR technique was used to investigate the CO 2 photoreduction process. The above characteristics together maximize the electron transfer efficiency, which causes the material has enhanced photocatalytic performance. [ABSTRACT FROM AUTHOR]

Pt@CeO 2 /3DCN heterojunction are prepared by calcination method and photoreduction technology. The enhanced photoreduction of CO 2 performance can be ascribed to the synergistic effects of the oxygen vacancies in CeO 2 for CO 2 activation and heterojunction for electron separation. Besides, Pt nanoparticles (NPs) on CeO 2 /3DCN can further promote the transfer of electrons, resulting in higher photocatalytic activity. • The Pt@CeO 2 /3DCN photocatalyst was successfully synthesized. • Pt@45CeO 2 /3DCN exhibit best ability of CO 2 photoreduction under UV light. • The synergy of CeO 2 and 3DCN improves the photocatalytic performance. The conversion of CO 2 into high value-added carbon-based compounds through photocatalytic reduction technology is considered as one of the more promising strategies to solve the greenhouse effect. And construction of heterojunction photocatalysts can promote the separation of photoelectron-hole pairs, so as to achieve higher activity of photocatalytic CO 2 reduction. Hence, Pt@CeO 2 /3DCN heterojunction are prepared by calcination method and photoreduction technology. The photocatalytic results revealed that Pt@CeO 2 /3DCN show better photocatalytic activity for reducing CO 2 into CO and CH 4 , compared with 3DCN. Especially, Pt@45CeO 2 /3DCN shows the maximum photocatalytic activity of 4.69 and 3.03 μmol·h−1·g−1 for CO and CH 4 under UV light irradiation, respectively, and the reduction activity did not decrease significantly after five cycles. The enhanced photoreduction of CO 2 performance can be ascribed to the synergistic effects of the oxygen vacancies in CeO 2 for CO 2 activation and heterojunction for electron separation. Besides, Pt nanoparticles (NPs) on CeO 2 /3DCN can further promote the transfer of electrons, resulting in higher photocatalytic activity. [ABSTRACT FROM AUTHOR]