In-situ fabrication of Bi_(2)S_(3)/BiVO_(4)/Mn_(0.5)Cd_(0.5)S-DETA ternary S-scheme heterostructure with effective interface charge separation and CO_(2) reduction performance

Exploring new and efficient photocatalysts to boost photocatalytic CO_(2) reduction is of critical importance for solar-to-fuel conversion.In this study,through the in-situ growth method,a series of S-scheme mechanism Bi_(2)S_(3)/BiVO_(4)/Mn_(0.5)Cd_(0.5)S-DETA nanocomposites with good photocatalytic activity were synthesized.The extremely small size of Mn_(0.5)Cd_(0.5)S-DETA nanoparticles provides more active sites for photocatalytic reactions.In order to solve the serious shortcomings of sulfide photo-corrosion,BiVO_(4) were introduced as oxidation catalyst to consume too many holes and improve the stability of the material.In addition,the in-situ growth method produces the reduction cocatalyst Bi_(2)S_(3) during the BiVO_(4) and Mn_(0.5)Cd_(0.5)S-DETA recombination process,thereby improving the efficiency of charge transfer at their interface contact.The ternary composite unveils a higher CO_(2)-reduction rate(44.74μmol g^(−1) h^(−1))comparing with pristine BiVO_(4)(14.11μmol g^(−1) h^(−1)).The enhanced photocatalytic CO_(2) reduction performance is due to the special interface structure of the S-scheme Bi_(2)S_(3)/BiVO_(4)/Mn_(0.5)Cd_(0.5)S-DETA photocatalyst,which facilitates the charge separation at the interface and improves its photocatalytic activity and stability.

Visible-Light-Promoted Formation of C-C and C-P Bonds Derived from Evolution of Bromoalkynes under Additive-Free Conditions:Synthesis of 1,1-Dibromo-1-en-3-ynes and Alkynylphosphine Oxides

Main observation and conclusion The controllable achievement of C-C and C-P bond formations is developed via visible-light-promoted bromoalkyne dimerization or its further transformation with secondary phosphine oxides.The 1,1-dibromo-1-en-3-ynes are formed when bromoalkyne is exposed to visible-light.While alkynylphosphine oxides are generated when bromoalkynes are mixed with secondary phosphine oxides.

Palladium-catalyzed tandem hydrocarbonylative cycloaddition for expedient construction of bridged lactones

A palladium-catalyzed tandem carbonylative lactonization and cycloaddition reaction of 2-vinyl acetophenones with alkenes and CO has been established.This reaction enables an efficient conversion of the easily available alkenes to various bridged lactones through intermolecular cycloaddition.

A hierarchical Bi-MOF-derived BiOBr/Mn_(0.2)Cd_(0.8)S S-scheme for visible-light-driven photocatalytic CO_(2) reduction

S-scheme heterojunctions have promising applications in photocatalytic CO_(2) reduction due to their unique structure and interfacial interactions,but improving their carrier separation efficiency and CO_(2) adsorption capacity remains a challenge.In this work,highly dispersed MOF-BiOBr/Mn_(0.2) Cd_(0.8) S(MOF-BiOBr/MCS)S-scheme heterojunctions with high photocatalytic CO_(2) reduction performance were constructed.The intimate contact between the MCS nano-spheres and the nanosheet-assembled MOF-BiOBr rods,driven by the internal electric field,accelerates the charge transfer along the S-scheme pathway.Moreover,the high specific surface area of MOFs is preserved to provide abundant active sites for reaction/adsorption.The formation of MOF-BiOBr/MCS S-scheme heterojunction is confirmed by theoretical calculations.The optimum MOF-BiOBr/MCS shows excellent activity in CO_(2) reduction,affording a high CO evolution rate of 60.59µmol h^(−1) g^(−1).The present work can inspire the exploration for the construction of effective heterostructure photocatalysts for photoreduction CO_(2).

A Direct Route to Tetrahydropyridazine Derivatives via DMAP-Catalyzed [4+2] Annulation of Allenoates with Arylazosulfones

Herein,a DMAP-catalyzed[4+2]annulation ofα-substituted allenoates with arylazosulfones is reported,which affords facile access to tetrahydropyridazine derivative in synthetically useful yields.This reaction features mild conditions and good functional group tolerance.Moreover,the resultant products can be readily transformed into pyridazin-3-one derivatives in the presence of DDQ.

乙基修饰的氮化碳增强光催化CO_(2)转化

光催化剂的表面官能团对光生载体的转移和反应的活性位点起着关键作用,对光催化转化过程影响很大.因此,合理准确地调控表面基团可以极大地优化光催化性能.本文通过引入给电子能力强的乙基,对氮化碳(g-C_(3)N_(4))未聚合的NH_(2)基团进行优化.通过X射线光电子能谱证实了乙基包埋的成功.时间分辨光谱和密度泛函理论(DFT)计算证实了光生载流子沿有利方向变化.最后,Gibbs自由能表明,乙基改性的氮化碳具有显著降低的CO_(2)转化为*COOH的能垒.其CO_(2)到CO的转化率为47.08μmolg^(-1)h^(-1).本研究为通过优化表面官能团来提高光催化剂性能的研究提供了可靠参考.

In_(2)O_(3)/Bi_(19)Br_(3)S_(27)S型异质结增强光催化CO_(2)还原

近年来,半导体催化剂因其较强的氧化还原能力和较好的稳定性而受到广泛关注.然而,光生电子和空穴对易复合和低氧化性导致单一半导体催化剂难以实现实际应用.深入研究表明,S型异质结具有独特的电子和空穴分离机理、强大的氧化还原能力和较强的载流子分离驱动力.本研究以在In_(2)O_(3)纳米球上生长的Bi_(19)Br_(3)S_(27)纳米花为原料,采用水热法合成了In_(2)O_(3)/Bi_(19)Br_(3)S_(27)梯形异质结.这种梯形异质结有效地促进了光生电荷载流子的分离和转移.结果表明,In_(2)O_(3)/Bi_(19)Br_(3)S_(27)复合材料对CO_(2)的还原产率高达28.36μmol h^(-1)g^(-1),分别是In_(2)O_(3)和Bi_(19)Br_(3)S_(27)的19和3.5倍.此外,通过原位漫反射红外傅里叶变换光谱对参与光催化反应的中间体进行了研究,揭示了光催化还原CO_(2)的反应过程.本工作为构建S型异质结光催化剂增强CO_(2)催化还原的方法提供了较好的研究思路.

Visible-light-induced chemoselective reactions of quinoxalin-2(1H)-ones with alkylboronic acids under air/N_(2) atmosphere

A visible-light-induced chemoselective reactions of quinoxalin-2(1 H)-ones with alkylboronic acids in the presence of air(O_(2)) and N_(2)atmosphere was developed under transition-metal free conditions, providing 3-alkylquinoxalin-2(1H)-ones and 3,4-dihydroquinoxalin-2(1H)-ones, respectively. The overall strategy accommodates a broad scope of substituted quinoxalin-2(1H)-ones and alkylboronic acids with good to excellent product yields.

Review on inorganic-organic S-scheme photocatalysts

The inorganic-organic S-scheme heterojunction photocatalyst demonstrates exceptional light absorption capacity,high photogenerated charge separation efficiency,and remarkable redox ability,while also inheriting diverse advantages of both inorganic and organic semiconductors.This paper provides a comprehensive review of recent advances in photocatalysis in relation to the inorganic-organic S-scheme heterojunction photocatalyst.Firstly,the fundamental aspects and benefits of the S-scheme heterojunction photocatalyst are outlined,followed by a discussion of several synthetic techniques for producing the inorganic-organic S-scheme heterojunction photocatalyst,as well as various advanced characterization methods that can verify the S-scheme heterojunction photocatalyst in both steady-state and transient processes.The impact of the inorganic-organic S-scheme heterojunction photocatalyst is illustrated with examples in fields such as carbon dioxide reduction,water splitting for hydrogen production,hydrogen peroxide synthesis,nitrogen fixation,organic pollutant degradation,organic transformation,and sterilization.Finally,suggestions are presented for designing the inorganic-organic S-scheme heterojunction photocatalyst and enhancing its photocatalytic performance.Undoubtedly,the inorganic-organic Sscheme heterojunction photocatalyst has emerged as a prominent and promising technology in the field of photocatalysis.

Single-layer crystalline triazine-based organic framework photocatalysts with different linking groups for H_(2)O_(2)production

Harnessing solar energy for photocatalytic hydrogen peroxide(H_(2)O_(2))synthesis represents a pinnacle of environmentally-sensitive and sustainable methodologies.While single-layer crystalline triazine-based organic frameworks(CTFs)are known for their prodigious photocatalytic potential in H_(2)O_(2)generation,ramifications of the connecting group within the triazine ring(TR)on underlying photocatalytic mechanism warrant deeper exploration.In this study,we simulate three distinct CTFs characterized by different TR linkers:CTF-1(benzene group(BG)),CTF-2(horizontally-oriented naphthyl group(NGH)),and CTF-DCN(vertically-oriented naphthyl group(NGV)).These diverse TR linkers profoundly modulate the absorption band edge of CTFs,subsequently dictating the orientation and constitution of the frontier orbitals.Such modulation plays a decisive role in determining the requisite energy for photoexcitation in CTFs,orchestrating the generation and distribution of photo-induced electrons and holes.Remarkably,the NGV linkage imparts CTF-DCN with unparalleled light ab-sorption,superior charge separation efficiency,and the lowest energy barrier for associated reactions.Through this investigation,we illuminate the pivotal influence of TR linkers in sculpting the photocatalytic dynamics of CTFs,providing fresh perspectives for architecting CTFs with amplified photocatalytic prowess in H_(2)O_(2)synthesis.

S-scheme Porous g-C_(3)N_(4)/Ag_(2)MoO_(4)Heterojunction Composite for CO_(2)Photoreduction

Utilizing solar energy to achieve artificial photosynthesis of chemical fuel is prevalent in tackling excessive CO_(2)emission and fossil fuel depletion.Grievous charge recombination and weak redox capability aggravate the CO_(2)photoreduction performance.Engineering tailored morphology and constructing matched heterostructure are two significant schemes to ameliorate the CO_(2)photoconversion efficiency of g-C_(3)N_(4)-based composite.Herein,a novel S-scheme ultrathin porous g-C_(3)N_(4)(UPCN)/Ag_(2)MoO_(4)(AMO)composite was designed by in-situ growing tetragonalα-AMO nanoparticles(NPs)(5-30 nm)on UPCN nanosheets(NSs).The S-scheme charge transfer route endows UPCN/AMO with fast charge separation and strong redox capability,demonstrated by X-ray photoelectron spectroscopy(XPS),photoelectrochemical tests,steady-state and time-resolved photoluminescence(PL)spectra,and DFT calculations.The UPCN/AMO composite exhibits elevated CO_(2)photoreduction performance with CO and CH_(4)yield rates of 6.98 and 0.38μmol g^(-1)h^(-1),which are 3.5 and 2.9 folds higher than that of pristine UPCN,respectively.Finally,the CO_(2)photoreduction intermediates are analyzed,and the CO_(2)photoreduction mechanism is discussed.This work provides a reference for various g-C_(3)N_(4)-based composites applied in artificial photosynthesis.

Graphitic carbon nitride/antimonene van der Waals heterostructure with enhanced photocatalytic CO_(2) reduction activity

Photocatalytic reduction of CO_(2) into valuable fuels is one of the potential strategies to solve the carbon cycle and energy crisis.Graphitic carbon nitride(g-C_(3)N_(4)),as a typical two-dimensional(2D)semiconductor with a bandgap of∼2.7 eV,has attracted wide attention in photocatalytic CO_(2) reduction.However,the performance of g-C_(3)N_(4) is greatly limited by the rapid recombination of photogenerated charge carriers and weak CO_(2) activation capacity.Construction of van der Waals heterostructure with the maximum interface contact area can improve the transfer/seperation efficiency of interface charge carriers.Ultrathin metal antimony(Sb)nanosheet(antimonene)with high carrier mobility and 2D layered structure,is a good candidate material to construct 2D/2D Sb/g-C_(3)N_(4) van der Waals heterostructure.In this work,the density functional theory(DFT)calculations indicated that antimonene has higher carrier mobility than g-C_(3)N_(4) nanosheets.Obvious charge transfer and in-plane structure distortion will occur at the interface of Sb/g-C_(3)N_(4),which endow stronger CO_(2) activation ability on di-coordinated N active site.The ultrathin g-C_(3)N_(4) and antimonene nanosheets were prepared by ultrasonic exfoliation method,and Sb/g-C_(3)N_(4) van der Waals heterostructures were constructed by self-assembly process.The photoluminescence(PL)and time-resolved photoluminescence(TRPL)indicated that the Sb/g-C_(3)N_(4) van der Waals heterostructures have a better photogenerated charge separation efficiency than pure g-C_(3)N_(4) nanosheets.In-situ FTIR spectroscopy demonstrated a stronger ability of CO_(2) activation to^ (∗)COOH on Sb/g-C_(3)N_(4) van der Waals heterostructure.As a result,the Sb/g-C_(3)N_(4) van der Waals heterostructures showed a higher CO yield with 2.03 umol g^(−1) h^(−1),which is 3.2 times that of pure g-C_(3)N_(4).This work provides a reference for activating CO_(2) and promoting CO_(2) reduction by van der Waals heterostructure.

Recent advances in special morphologic photocatalysts for NO_(x)removal

The significant increase of NO_(x)concentration causes severe damages to environment and human health.Light-driven photocatalytic technique affords an ideal solution for the removal of NO_(x)at ambient conditions.To enhance the performance of NO_(x)removal,1D,2D and 3D photocatalysts have been constructed as the light absorption and the separation of charge carriers can be manipulated through controlling the morphology of the photocatalyst.Related works mainly focused on the construction and modification of special morphologic photocatalyst,including element doping,heterostructure constructing,crystal facet exposing,defect sites introducing and so on.Moreover,the excellent performance of the photocatalytic NO_(x)removal creates great awareness of the application,which has promising practical applications in NO_(x)removal by paint(removing NO_(x)indoor and outdoor)and pavement(degrading vehicle exhausts).For these considerations,recent advances in special morphologic photocatalysts for NO_(x)removal was summarized and commented in this review.The purpose is to provide insights into understanding the relationship between morphology and photocatalytic performance,meanwhile,to promote the application of photocatalytic technology in NO_(x)degradation.