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1.
Transl Vis Sci Technol ; 8(6): 22, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31788351

RESUMO

Purpose: To investigate the association between changes in arterial blood gases and intraocular pressure (IOP) after acute, short-term exposure to simulated elevation of 4000 m above sea level. Methods: Twenty-five healthy young lowlanders participated in this prospective study. IOP was measured in both eyes with an Accupen tonometer. Arterial blood gas parameters (partial oxygen pressure [PaO2], partial carbon dioxide pressure [PaCO2], pH, and bicarbonate ion [HCO3 -]) were checked using a blood gas analyzer. Measurements were taken at sea level (T1), at 15-minute (T2) and at 2-hour (T3) exposure times to simulated 4000 m above sea level in a hypobaric chamber, and upon return to sea level (T4). Associations between arterial blood gas parameters and IOP were evaluated using multivariate linear regression. Results: PaO2 significantly decreased at T2 and T3, resolving at T4 (P < 0.001). pH significantly increased at T2 and returned to baseline at T3 (P = 0.004). Actual and standard bicarbonate ion both dropped with IOP at T3 and T4. IOP significantly decreased from 16.4 ± 3.4 mm Hg at T1 to 15.1 ± 2.1 mm Hg (P = 0.041) at T3 and remained lower (14.9 ± 2.4 mm Hg; P = 0.029) at T4. IOP was not correlated with pH. Multivariate linear regression showed that lower IOP was associated with lower standard bicarbonate ion (beta = -1.061; 95% confidence interval, -0.049 to -2.074; P = 0.04) when adjusted for actual bicarbonate and diastolic blood pressure. Conclusions: Hypobaric hypoxia triggers plasma bicarbonate ion reduction which, rather than pH, may decrease aqueous humor formation and subsequently cause IOP reduction. These findings may shed light on the mechanism of IOP regulation at high altitude. Translational Relevance: Hypoxia-triggered reduction in plasma bicarbonate ion may decrease aqueous humor production, leading to IOP reduction at high altitude. These findings may provide new insight into a potential mechanism of IOP regulation. Hypobaric hypoxia at high altitude is an environmental factor that can reduce IOP and, therefore, deserves further study.

2.
ACS Appl Mater Interfaces ; 11(47): 44186-44195, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31692330

RESUMO

This work reports the synthesis of core-shell structured Au@C composite through a simple one-step laser ablation technique. The results demonstrate that the Au@C with a mean nanosphere size of ∼8.0 nm is composed of a spherical shaped Au core and 1-2 layered graphitic carbon shell with abundant defects. As a nitrogen reduction reaction (NRR) electrocatalyst, the Au@C gives a large NH3 yield rate of 241.9 µg h-1 mgcat.-1 with a high faradaic efficiency of 40.5% at -0.45 V versus reversible hydrogen electrode in a 0.1 M Na2SO4 electrolyte (pH = 6.3) under ambient conditions, surpassing the performances of most aqueous-based NRR electrocatalysts recently reported. The 15N labeling experimental results demonstrate that the produced NH3 is undoubtedly originated from the NRR process catalyzed by Au@C. The superior NRR performance of Au@C can be ascribed to the ultrathin carbon layer, effectively inhibiting the aggregation of Au nanospheres during the NRR, and the abundant defects such as carbon vacancies existed in the ultrathin carbon layer, providing additional NRR catalytic active sites. Our theoretical calculation results further confirm the role of carbon vacancies in the electrocatalytic NRR.

3.
Adv Mater ; 31(49): e1906051, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31621962

RESUMO

Selective hydrogenation of quinoline and its derivatives is an important means to produce corresponding 1,2,3,4-tetrahydroquinolines for a wide spectrum of applications. A facile and efficient "laser irradiation in liquid" technique to liberate the inaccessible highly dispersed CoNx active sites confined inside N-doped carbon nanotubes is demonstrated. The liberated CoNx sites possess generic catalytic activities toward selective hydrogenation of quinoline and its hydroxyl, methyl, and halogen substituted derivatives into corresponding 1,2,3,4-tetrahydroquinolines with almost 100% conversion efficiency and selectivity. This laser irradiation treatment approach should be widely applicable to unlock the catalytic powers of inaccessible catalytic active sites confined by other materials.

4.
Chem Commun (Camb) ; 55(82): 12376-12379, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31559991

RESUMO

We report a pyrolysis-phosphorization approach to fabricate carbon nanotubes with embedded CoP nanoparticles (CoP/CNs) using ZIF-67 as a precursor for electrocatalytic nitrogen (N2) reduction to ammonia (NH3) under ambient conditions. The results demonstrate that the as-synthesized CoP/CNs as electrocatalysts exhibit high electrocatalytic activity toward the N2 reduction reaction (NRR), affording a large NH3 yield rate of 48.9 µg h-1 mgcat.-1 with a faradaic efficiency (FE) of 8.7% at -0.4 V (vs. RHE) in 0.1 M Na2SO4 electrolyte. The 15N isotopic labelling experiments confirm that the NH3 obtained is indeed from the CoP/CN catalyzed NRR process. Our theoretical calculation results reveal that the N2 molecules prefer to be adsorbed on the highly unsaturated three coordinated Co sites of the CoP(112) plane following an associative distal hydrogenation process.

5.
Angew Chem Int Ed Engl ; 58(46): 16644-16650, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31497911

RESUMO

As a metal-free nitrogen reduction reaction (NRR) photocatalyst, g-C3 N4 is available from a scalable synthesis at low cost. Importantly, it can be readily functionalized to enhance photocatalytic activities. However, the use of g-C3 N4 -based photocatalysts for the NRR has been questioned because of the elusive mechanism and the involvement of N defects. This work reports the synthesis of a g-C3 N4 photocatalyst modified with cyano groups and intercalated K+ (mCNN), possessing extended visible-light harvesting capacity and superior photocatalytic NRR activity (NH3 yield: 3.42 mmol g-1 h-1 ). Experimental and theoretical studies suggest that the -C≡N in mCNN can be regenerated through a pathway analogous to Mars van Krevelen process with the aid of the intercalated K+ . The results confirm that the regeneration of the cyano group not only enhances photocatalytic activity and sustains the catalytic cycle, but also stabilizes the photocatalyst.

6.
Coron Artery Dis ; 30(7): 473-480, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31464729

RESUMO

OBJECTIVE: Approximately, 10-20% of patients with drug eluting stent (DES) in-stent restenosis (ISR) will develop recurrent ISR; yet, the optimal management of recurrent DES-ISR is unknown. We sought to compare the outcomes of recurrent DES-ISR treated with drug eluting balloons (DEB) to those with repeated implantation of new-generation DES. METHODS: A total of 172 patients with recurrent DES-ISR were enrolled and stratified into two cohorts: the repeated DES implantation (Re-DES) group and the DEB group. The primary endpoint was the 1-year incidence of major adverse cardiovascular events (MACE). RESULTS: Ninety-three patients treated with DEB and 79 patients with Re-DES implantation were analyzed. Both groups had comparable baseline characteristics. Lesser residual stenosis was achieved in the Re-DES group (11.3 ± 3.2% vs. 22.4 ± 4.3%; P = 0.00) than in the DEB group. However, the incidence of MACE and target lesion revascularization (TLR) were less in the DEB group (17.2% vs. 32.9%; P = 0.02 and 15.1% vs. 27.8%; P = 0.04, respectively). For the ≥3 metal-layered DES-ISR subgroup, DEB drastically reduced the incidences of MACE and TLR compared with Re-DES (20.0% vs. 57.9%; P = 0.02 and 16.0% vs. 47.4%; P = 0.04, respectively). Survival analysis demonstrated that MACE-free survival was significantly higher in the DEB group compared with the Re-DES group, whether the metal layers were ≥3 or 2. Multivariate analysis revealed that the risk factors of MACE were diabetes mellitus, ≥3 metal-layered DES ISR, and repeat DES deployment. CONCLUSIONS: For recurrent DES-ISR, DEB may improve clinical outcomes compared with Re-DES implantation, especially for ≥3 metal-layered DES-ISR.

7.
Nanoscale ; 11(25): 12161-12168, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31197303

RESUMO

Frequent oil spill accidents and ever-increasing oily wastewater have become serious global environmental problems. To enhance the oil-sorption capacity and simplify the oil-recovery process, the construction of various advanced oil sorbents and oil-collecting devices is of great technological importance. Herein, a three-dimensional (3D) porous carbon-based hybrid monolith has been successfully fabricated, in which cobalt based metal-organic framework (Co-MOF) nanosheets are firstly immobilized on a carbon foam (CF) skeleton (denoted as Co-MOFs/CF) via a facile vapor-phase hydrothermal (VPH) technique followed by carbonation treatment under a N2 atmosphere into Co@C/CF. The resulting Co@C/CF hybrid monolith exhibits an exceptional oil/water separation ability, including high sorption capacity (from 85 to 200 times its own weight toward various solvents and oils), easy collection and remarkable recyclability, as reflected by no obvious reduction in uptake capacity even after 20 cycles of repeated operation. More significantly, the oil-collecting device based on the proposed carbon-based hybrid monolith can rapidly, efficiently, and continuously collect oil from water surfaces, making it a promising candidate for oil-spill remediation.

8.
BMC Cardiovasc Disord ; 19(1): 109, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088360

RESUMO

BACKGROUND: The rational length of stay following non-complicated percutaneous coronary intervention (PCI) for Non-ST elevation myocardial infarction (NSTEMI) patients remains controversial. Few studies have examined the impact of early discharge on short-term outcomes in NSTEMI patients, but short-time discharge is not uncommon in real world practice. This study examined the impact of short time discharge following non-complicated PCI on 30-day net adverse clinical events in NSTEMI patients. METHODS: This retrospective study enrolled 1424 consecutive patients with NSTEMI diagnoses who underwent non-complicated PCI. Of these patients, 432 were discharged early (< 24 h), whereas the remaining 992 NSTEMI patients underwent routine discharge. The primary end points of the study were the net adverse clinical events including major adverse cardiac or cerebral events or access site vascular/bleeding complications within 30 days. The differences between the two groups were analyzed after propensity score matching to reduce selection bias. RESULTS: The incidence of crude 30-day net adverse events was numerically higher in the long-time discharge group at 11.6% (115/992) compared with 8.6% (37/432) in the short-time discharge group, although this difference was not significant (P = 0.09). This difference was mainly due to lesser radial access selected in the long-time discharge group (827/932, 83.4% vs. 387/432, 89.5%, P < 0.0005). After PS matching to balance the access difference, there was no significant difference in the incidence of the events mentioned above between two groups. CONCLUSIONS: If an NSTEMI patient undergoes PCI without any procedural or hospital complications, short-time discharge after successful PCI would be feasible and safe in selected NSTEMI patients.

9.
Phys Chem Chem Phys ; 21(11): 5950-5955, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30815666

RESUMO

It is highly attractive but challenging to develop earth-abundant electrocatalysts for nitrogen (N2) fixation. Here, by using density functional theory (DFT), we systematically investigate various single transition metal atom (Ti, V, Cr, Mn, Fe, Co, Ni, Ru, Rh and Pd) modified MoP surfaces as potential N2 reduction electrocatalysts for ammonia (NH3) synthesis. Through comparison of the stabilities of metal atom modified MoP, the adsorption energies and the bond lengths of N2 on different atom modified MoP, we select Mn and V as two candidates and study in detail the possible N2 reduction reaction (NRR) pathways for Mn-MoP and V-MoP. Our results revealed that Mn-MoP and V-MoP exhibit energy change values of 0.95 eV and 0.65 eV, respectively, with the first hydrogenation step being the potential-limiting step. Mn-MoP can efficiently suppress *H adsorption and reduce the competition of the hygrogen evolution reaction (HER) with the NRR; whereas, V-MoP cannot. Therefore, Mn-MoP is a better catalyst to realize the nitrogen reduction reaction. Overall, this work takes one step toward the NRR possibility of transition metal phosphides and provides some important insights and guidance to experiments.

10.
J Colloid Interface Sci ; 542: 269-280, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30763894

RESUMO

Environmental concern associated with excess fluoride has intrigued the unceasing exploration of new multifunctional hybrid materials to mitigate any undesirable consequence to human health. Herein, a novel hybrid monolith has been successfully fabricated via a facile in-situ growth strategy for highly efficient defluoridation from contaminated waters, in which homogeneously dispersed UiO-66 particles are perfectly anchored on three dimensional (3D) porous carbon foam (CF). Benefiting from fully exposed active sites, excellent pore accessibility and efficient mass transport, the integrated UiO-66/CF hybrid monolith exhibits fast adsorption kinetics, and outstanding uptake capacity toward fluoride as high as 295 mg g-1, which greatly outperforms the previously reported adsorbents. Furthermore, the fluoride removal efficiency of the spent monolith can reach up to 70% after four cycles, accompanied by facile separation nature and outstanding water stability. More significantly, the resulting UiO-66/CF packed column (0.36 g) can continuously treat 400 mL of F- solution with 6.2 mg L-1 before the breakthrough point occurs, highlight its potential feasibility for fluoride removal in the practical applicability.

11.
Chemistry ; 25(23): 5904-5911, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30767346

RESUMO

Electrosynthesis of NH3 through the N2 reduction reaction (NRR) under ambient conditions is regarded as promising technology to replace the industrial energy- and capital-intensive Haber-Bosch process. Herein, a room-temperature spontaneous redox approach to fabricate a core-shell-structured Au@CeO2 composite, with Au nanoparticle sizes below about 10 nm and a loading amount of 3.6 wt %, is reported for the NRR. The results demonstrate that as-synthesized Au@CeO2 possesses a surface area of 40.7 m2 g-1 and a porous structure. As an electrocatalyst, it exhibits high NRR activity, with an NH3 yield rate of 28.2 µg h-1 cm-2 (10.6 µg h-1 mg-1 cat. , 293.8 µg h-1 mg-1 Au ) and a faradaic efficiency of 9.50 % at -0.4 V versus a reversible hydrogen electrode in 0.01 m H2 SO4 electrolyte. The characterization results reveal the presence of rich oxygen vacancies in the CeO2 nanoparticle shell of Au@CeO2 ; these are favorable for N2 adsorption and activation for the NRR. This has been further verified by theoretical calculations. The abundant oxygen vacancies in the CeO2 nanoparticle shell, combined with the Au nanoparticle core of Au@CeO2 , are electrocatalytically active sites for the NRR, and thus, synergistically enhance the conversion of N2 into NH3 .

12.
Chem Commun (Camb) ; 55(20): 2952-2955, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30778469

RESUMO

Here, we report the synthesis of Cu-doped CeO2 nanorods (denoted as Cu-CeO2-x, x represents the mass content (wt%) of the doped Cu) by a facile hydrothermal method, followed by thermal treatment in an H2/Ar atmosphere. As the electrocatalyst, Cu-CeO2-3.9 with a large surface area of 95.2 m2 g-1 and mesoporous structure exhibits high electrocatalytic activity toward the N2 reduction reaction (NRR), delivering an NH3 yield rate of 5.3 × 10-10 mol s-1 cm-2 and a faradaic efficiency of 19.1% at -0.45 V (vs. RHE) in a 0.1 M Na2SO4 electrolyte (pH = 6.3), much higher than the NRR performance achieved with pure CeO2 nanorods. The Cu doping can effectively tune the concentration of multiple oxygen vacancies in CeO2, thus resulting in significantly improved NRR activity.

13.
Chem Commun (Camb) ; 55(16): 2344-2347, 2019 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-30724313

RESUMO

Commercial carbon fiber cloth treated at 450 °C in air (CFC-450) possesses low C[double bond, length as m-dash]O content, exhibiting outstanding oxygen evolution activity in 1.0 M KOH electrolyte with an overpotential of 224 mV at current density of 10 mA cm-2. Meanwhile, we observed an electrochemical corrosion phenomenon associated with the carbon fiber cloth electrocatalyst during the OER tests, especially under high static potentials.

14.
Adv Mater ; 31(11): e1808341, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30672034

RESUMO

Biomass is the most abundant renewable resource on earth and developing high-performance nonprecious selective hydrogenation (SH) catalysts will enable the use of biomass to replace rapidly diminishing fossil resources. This work utilizes ZIF-67-derived nitrogen-doped carbon nanotubes to confine Co nanoparticles (NPs) with Co-Nx active sites as a high-performance SH catalyst. The confined Co NPs with Co-Nx exhibit excellent catalytic activity, selectivity, and stability toward a wide range of biomass-derived compounds. Such active sites can selectively hydrogenate aldehyde, ketone, carboxyl, and nitro groups of biomass-derived compounds into value-added fine chemicals with 100% selectivity. The reported approach could be adopted to create other forms of catalytically active sites from other nonprecious metals.

15.
Dalton Trans ; 47(48): 17276-17284, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30427348

RESUMO

Water is inevitably associated with the production of bio-derived platform molecules, but most supported metallic catalysts have poor water compatibility. Although there have been a great number of investigations regarding the hydrogenation of bio-derived unsaturated compounds in the organic phase, the reactions that proceed in water are still quite challenging. Herein, we report the synthesis of a supported nickel catalyst (Ni-LN650) by the reduction of the perovskite-type oxide LaNiO3 precursor at 650 °C. The derived catalyst affords attractive activity in the hydrogenation of furfural by using water as the reaction medium, in which furfural is completely converted into tetrahydrofurfuryl alcohol with the highest productivity of 289.7 mmol gNi-1 h-1 at 120 °C and 1 MPa of H2 within 5 h of reaction. The Ni-LN650 catalyst also exhibits good stability and renewability in a cycle test, stemming from the self-regeneration peculiarity of the perovskite-type oxide precursor. Moreover, the catalyst can also demonstrate high activity in the aqueous-phase hydrogenation of various aldehydes, alkenes and carboxylic acids in a series of experiments. Due to the merits of usability in water, the renewability and wide application scope, the Ni-LN650 catalyst can be treated as a promising candidate for the catalytic conversion of bio-derived platform molecules into high value-added fuels and chemicals.

16.
Sensors (Basel) ; 18(11)2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30441871

RESUMO

A joint resource allocation algorithm to minimize the system outage probability is proposed for a decode-and-forward (DF) two-way relay network with simultaneous wireless information and power transfer (SWIPT) under a total power constraint. In this network, the two sources nodes exchange information with the help of a passive relay, which is assumed to help the two source nodes' communication without consuming its own energy by exploiting an energy-harvesting protocol, the power splitting (PS) protocol. An optimization framework to jointly optimize power allocation (PA) at the source nodes and PS at the relay is developed. Since the formulated joint optimization problem is non-convex, the solution is developed in two steps. First, the conditionally optimal PS ratio at the relay node for a given PA ratio is explored; then, the closed-form of the optimal PA in the sense of minimizing the system outage probability with instantaneous channel state information (CSI) is derived. Analysis shows that the optimal design depends on the channel condition and the rate threshold. Simulation results are obtained to validate the analytical results. Comparison with three existing schemes shows that the proposed optimized scheme has the minimum system outage probability.

17.
Water Res ; 147: 223-232, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30312795

RESUMO

In an effort to provide early warnings for the occurrence of eutrophication, it is highly desirable to develop an accurate and efficient technique to ensure continuous monitoring of dissolved reactive phosphorus (DRP) in the aquatic environment from the viewpoint of environmental management. Herein, a new diffusive gradient in thin film (DGT) technique was developed and evaluated for in situ measurement of DRP in waters, in which Zr-based metal organic frameworks (MOFs, UiO-66) were utilized as aqueous binding agent (abbreviated as UiO-66 DGT). As expected, the UiO-66 DGT demonstrated high uptake capacity towards phosphorus (20.8 µg P cm-2). Meanwhile, an excellent linearity between the accumulated DRP mass and deployment time over 5 d (R2 = 0.996) was obtained regardless of high or low phosphate solution. In addition, effective diffusion coefficients (D) of DRP increased exponentially with increasing ionic strengths (R2 = 0.99). Based on the rectified D, the performance of the UiO-66 DGT was independent of solution pH (6.5-8.5) and ionic strengths (ranging from 0.01 to 100 mmol L-1). Furthermore, field deployments of the UiO-66 DGT were undertaken in a natural eutrophic lake (Lake Chaohu, China). It was noteworthy that DRP could be continually accumulated by the UiO-66 DGT for more than 14 d and good agreements were obtained between the concentrations measured by DGT (CDGT) and those by ex situ chemical extraction method in solution (Csol), as reflected by CDGT/Csol of 0.9-1.1. In situ determination of DRP speciation was also carried out at different sites across Lake Chaohu. Overall, this study contributed to a better constructing of liquid binding phase DGT for the measurement of DRP in waters, facilitating the widespread application of the UiO-66 DGT as a routine monitoring technique and for large-scale environmental analysis.


Assuntos
Estruturas Metalorgânicas , Fósforo , China , Difusão , Monitoramento Ambiental , Zircônio
18.
Chem Commun (Camb) ; 54(79): 11188-11191, 2018 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-30229239

RESUMO

Nitrogen-free commercial carbon cloth treated at 450 °C in air possesses abundant defects, exhibiting superior electrocatalytic activity for the nitrogen reduction reaction (NRR) with an NH3 yield of 2.59 × 10-10 mol cm-2 s-1 and a Faradaic efficiency of 6.92% at -0.3 V (vs. RHE) in 0.1 M Na2SO4 + 0.02 M H2SO4.

19.
J Colloid Interface Sci ; 532: 37-46, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30077065

RESUMO

We investigate the possibility of utilizing benzyl alcohol oxidation reaction to replace sluggish oxygen evolution reaction (OER) for the charging process in a rechargeable zinc-air battery, catalyzed by NiCo alloy nanoparticles supported on activated carbon (NiCo/AC) with the multifunctional electrocatalytic activities of the oxygen reduction, oxygen evolution and benzyl alcohol oxidation reactions. As an electrocatalyst for the oxygen reduction reaction (OER), NiCo/AC exhibits superior catalytic activity with an onset potential of 0.85 V (vs. RHE), a half-wave potential of 0.74 V (vs. RHE) and a large limiting current density of 4.65 mA cm-2 at 0.2 V (vs. RHE). Moreover, NiCo/AC also demonstrates the electrocatalytic oxidation activities toward water and benzyl alcohol, moreover, the benzyl alcohol oxidation reaction is more thermodynamically and kinetically favourable with 254 mV smaller overpotential than water oxidation at 10 mA cm-2. Owing to these advantages, NiCo/AC as air cathode material is assembled into a home-made rechargeable zinc-air battery, resulting an almost 200 mV lower charging voltage at the current density of 50 mA cm-2 in the presence of 0.1 M benzyl alcohol compared to the battery without benzyl alcohol, consequently obtaining 10.5% energy saving at the charging current density of 50 mA cm-2 with high durability.

20.
ACS Appl Mater Interfaces ; 10(37): 31394-31403, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30141620

RESUMO

We present the self-assembly synthesis of core-shell structure Au/CeO2 composites with different Au loadings through a spontaneous chemical redox approach at an ambient temperature utilizing HAuCl4 and Ce(NO3)3 as reaction substrates in an alkaline environment. The results demonstrate that the as-synthesized Au/CeO2 composites exhibit spherical shape morphologies with porous structures, composed of Au nanoparticle (∼10 nm) cores and CeO2 nanoparticle shells with abundant oxygen vacancies. The introduction of Au nanoparticles in CeO2 not only effectively improves the visible light utilization efficiency but also provides rich surface catalytic active sites for highly efficient visible light photocatalysis. As visible light photocatalysts (λ > 400 nm), the as-synthesized Au/CeO2 composites with the Au loading amount ≥4.0 wt % exhibit high conversion and selectivity (∼100%) of benzyl alcohol to benzaldehyde under the given experimental conditions. Moreover, Au/CeO2 also shows a general applicability as a visible light photocatalyst for the selective oxidation of other alcohols to corresponding aldehydes or ketones. The photocatalytic mechanism studies indicate that the photoelectrons/holes produced from the photoexcited Au and the formed superoxide radicals in the oxygen vacancies of CeO2 synergistically contribute to the high performance of the selective photocatalytic oxidation of alcohols to aldehydes or ketones.

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