Deciphering the potassium storage phase conversion mechanism of phosphorus by combined solid-state NMR spectroscopy and density functional theory calculations

Phosphorus is the potential anode material for emerging potassium-ion batteries(PIBs)owing to the highest specific capacity and relatively low operation plateau.However,the reversible delivered capacities of phosphorus-based anodes,in reality,are far from the theoretical capacity corresponding to the formation of K3P alloy.And,their underlying potassium storage mechanisms remain poorly understood.To address this issue,for the first time,we perform high-resolution solid-state31P NMR combined with XRD measurements,and density functional theory calculations to yield a systemic quantitative understanding of(de)potassiation reaction mechanism of phosphorus anode.We explicitly reveal a previously unknown asymmetrical nanocrystalline-to-amorphous transition process via rP←→(K_(3)P_(11),K_(3)P_(7),beta-K_(4)P_(6))←→(alpha-K4P6)←→(K_(1-x)P,KP,K_(4-x)P3,K_(1+x)P)←→(amorphous K4P3,amorphous K3P)that are proceed along with the electrochemical potassiation/depotassiation processes.Additionally,the corresponding KP alloys intermediates,such as the amorphous phases of K_(4)P_(3),K_(3)P,and the nonstoichiometric phases of“K_(1-x)P”,“K_(1+x)P”,“K_(4-x)P_(3)”are experimentally detected,which indicating various complicated K-P alloy species are coexisted and evolved with the sluggish electrochemical reaction kinetics,resulting in lower capacity of phosphorus-based anodes.Our findings offer some insights into the specific multi-phase evolution mechanism of alloying anodes that may be generally involved in conversion-type electrode materials for PIBs.

Research progress in electrospinning engineering for all-solid-state electrolytes of lithium metal batteries

Owing to safety issue and low energy density of liquid lithium-ion batteries(LIBs),all-solid-state lithium metal batteries(ASLMBs)with unique all-solid-state electrolytes(SEs)have attracted wide attentions.This arises mainly from the advantages of the SEs in the suppression of lithium dendrite growth,long cycle life,and broad working temperature range,showing huge potential applications in electronic devices,electric vehicles,smart grids,and biomedical devices.However,SEs suffer from low lithiumion conductivity and low mechanical integrity,slowing down the development of practical ASLMBs.Nanostructure engineering is of great efficiency in tuning the structure and composition of the SEs with improved lithium-ion conductivity and mechanical integrity.Among various available technologies for nanostructure engineering,electrospinning is a promising technique because of its simple operation,cost-effectiveness,and efficient integration with different components.In this review,we will first give a simple description of the electrospinning process.Then,the use of electrospinning technique in the synthesis of various SEs is summarized,for example,organic nanofibrous matrix,organic/inorganic nanofibrous matrix,and inorganic nanofibrous matrix combined with other components.The current development of the advanced architectures of SEs through electrospinning technology is also presented to provide references and ideas for designing high-performance ASLMBs.Finally,an outlook and further challenges in the preparation of advanced SEs for ASLMBs through electrospinning engineering are given.

Synthesis,Crystal Structure and Photoluminescence of a Dinulear Copper Complex

A binuclear cuprous complex [Cu（μ-I）（NPPh）]2（1,NPPh = 1-（2-（diphenylphosphanyl）phenyl）-3-phenyl-4,5-dihydro-1 H-pyrazole） was synthesized and characterized by elemental analysis,NMR and X-ray single-crystal structure analysis.It crystallizes in triclinic space group P2_1/n with a = 10.7520（3）,b = 18.1860（5）,c = 11.8487（3） ？,β = 91.864（2）,V = 2315.61（11） ？~3,Z = 4,Mr = 594.87,Dc = 1.706 g/cm^3,F（000） = 1176.0,μ = 12.582 mm（-1）,GOOF = 1.048,the final R = 0.0289 and wR = 0.0670 for 3787 observed reflections with I 〉 2σ（I）.The Cu atoms in the complex are four-coordinated and adopt distorted tetrahedral coordination geometry.In the solid state,the complex exhibits greenish yellow photoluminescence with a peak maximum of 533 nm,a decay time of 34 μs,and a photoluminescence quantum yield of 63.6% at room temperature,respectively.

Syntheses and Crystal Structures of Two New Supramolecular Architectures Constructed from the Main Group Metal Chloride and Protonated 2-(3-Pyridyl)benzimidazole

The reactions of SbCl3 and HgCl2 with 2-（3-pyridyl）benzimidazole （PyBIm） in solution acidified with HCl have been investigated. The PyBIm ligands are protonated into 2-（3-pyridinio）benzimidazolium （H2PyBIm） cations and the corresponding metal ions are bonded with chloride atoms into coordination anions, forming two new coordination compounds, namely, （H2PyBIm）（SbCl5） 1 and （H2PyBIm）2（Hg2Cl8） 2. Both compounds were characterized by X-ray crystallography. Crystal data for 1： triclinic, space group P1^- with a = 5.7030（7）, b = 9.0625（11）, c = 16.5929（18） A, α = 91.808（7）°, β = 93.234（6）, γ = 99.216（7）°, C12H11N3SbCl5, Mr = 496.24, V = 844.44（17） A^3, Z = 2, Dc = 1.952 g/cm^3, μ（MoKα） = 2.419 mm^-1, F（000） = 480, the final R = 0.0496 and wR = 0.1382 for 3433 observed reflections （I 〉 2σ（I））. Crystal data for 2： monoclinic, space group P21/c with a = 7.8061（5）, b = 15.8127（9）, c = 12.2435（9） , β = 91.955（4）o, C24H22N6Hg2Cl8, Mr = 1079.26, V = 1510.40（17） 3, Z = 2, Dc = 2.373 g/cm3, μ（MoKα） = 10.889 mm-1, F（000） = 1008, the final R = 0.0293 and wR = 0.0562 for 2854 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that the antimony（III） is five-coordinated, exhibiting a slightly distorted square-pyramidal coordination geometry; while in 2, a dimeric [Hg2Cl8]^4-anion consists of two trigonal bipyramids sharing two common edges. The organic cations and coordination anions are connected into a one-dimensional belt and a two-dimensional sheet through N-H···Cl hydrogen bonding interactions in compounds 1 and 2, respectively; both are further aggregated into 3D frameworks by strong π-π contacts.

Pre-fixing defects in carbon framework for revealing the active sites of oxygen reduction reaction at nitrogen-doped carbon nanotubes

Nitrogen-doped carbon-based materials are promising non-platinum group metal electrocatalysts for the oxygen reduction reaction(ORR).Understanding their ORR active sites is vital for the rational design and development of nitrogen-doped carbon-based electrocatalysts with enhanced catalytic efficiency and selectivity.However,the conclusive analysis of the ORR mechanism of nitrogen-doped carbon-based electrocatalysts remains a grand challenge because the catalysts have a complex inhomogeneous structure.Here,we elucidate this problem using nitrogen-doped carbon nanotubes framework catalysts with fixed defect concentrations prepared by pre-thermal treatment at a low temperature.The generation of defects under high-temperature treatment was effectively suppressed to enable a simple model for ORR mechanism study.A correlation between ORR pathways and the different nitrogen species in the nitrogen-doped carbon catalysts was revealed through a combination of structural and electrochemical properties investigations.Besides,our results also demonstrate the importance of defects for ORR.We believe that the results will provide instructive guidance for designing and developing novel carbon nanomaterials for ORR.

Synthesis and Crystal Structure of a Two-dimensional Cadmium Complex Based on Terephthalate and 1-Methyl-2,2'-bibenzimidazole

The title complex, [Cd（MeHbibzim）（1,4-bdc）]n （1, MelToibzim = 1-methyl-2,2＇- bibenzimidazole, 1,4-bdc = terephthalate）, was synthesized with hydrothermal reactions. The compound crystallizes in monoclinic, space group C2/c with a = 9.822（4）, b = 18.510（7）, c = 22.372（9） A, β = 98.359（6）°, C23H16CdN4O4, Mr = 524.81, V= 4024（3） A3, Z = 8, Dc. = 1.733 g/cm3, μ（MoKa） = 1.126 mm-1, F（000） = 2096, the final R = 0.0597 and wR = 0.1374 for 3906 observed reflections （1 〉 2σ（I））. X-ray diffraction analysis reveals that the Cd atom is coordinated by two nitrogen atoms from the chelating MeHbibzim and three carboxyl oxygen atoms from three terephthalate ligands, thus forming a distorted square pyramidal coordination sphere, [CdN2O3]. Every two Cd atoms are linked together via two carboxyl groups into a dinuclear unit with Cd...Cd separation of 3.806（4） A. The dinuclear building units are linked by terephthalate ligands into two-dimensional layers, which are further aggregated into a 3D framework via hydrogen bonding interactions.

Photocatalytic Oxidation of Low Molecular Weight Hydrocarbon Gases over Pt-TiO2 Nanotubes

Pt-TiO2 nanotubes with tube diameter of -120 nm and uniformly dispersed Pt particles（size of -2 nm） were successfully synthesized via a carbon nanotube（CNT） templating method followed by a photo-deposition processing of Pt nanoparticles. The as-obtained Pt-TiO2 NTs possess both enhanced visible light absorption and reduced recombination of photogenerated electrons and holes. These merits boost the Pt-TiO2 NTs an excellent photocatalytic material toward photooxidation of a variety of low molecular hydrocarbons under atmospheric environment.

Synthesis, Structure and Electrocatalytic Activity of Perfluorinated Covalent Triazine-based Framework

Using the bottom-up method, we synthesized a series of perfluorinated covalent triazine-based frameworks(FCTFs) with porous structures for catalysis oxygen reduction reaction(ORR). The evolved FCTFs by high-temperature carbonization show an apparent variation in electrocatalytic activity toward the ORR dependent on the type of F. The samples synthesized at 900 ℃(FCTF-900) exhibits advantages in terms of high activity, high durability, and methanol-tolerant as an efficient electrocatalyst for ORR, manifests a comparable or even better activity as compared with the commercial Pt/C catalysts not only in alkaline media but also in acidic and neutral electrolyte.

Synthesis and Crystal Structure of a Cobalt(Ⅱ)Complex Based on 2,2-Bibenzimidazole and N,N-bis(phosphonomethyl)aminoacetic Acid

The title complex, [Co2（bibzim）（H2bibzim）4]·Co2（H2bibzim）2（Hbibzim）（HL）]2- 2H2O （1） （HEbibzim = 2,2＇-bibenzimidazole, H5L = N,N-bis（phosphonomethyl）aminoacetic acid （HO2CCH2N（CH2PO3H2）2））, was synthesized with hydrothermal reactions. The compound crystallizes in triclinic, space group P1 with a = 13.71020（10）, b = 14.9165（5）, c = 20.9924（5） A, a = 86.344（9）, β = 71.214（8）, γ = 73.757（7）°, C162HI24Co6N46O18P4, Mr = 3478.52, V = 3900.55（16） A3, Z = 2, Dc = 1.482 g/cm3,μ（MoKa） = 0.747 mm^-1, F（000） = 1784, the final R = 0.0777 and wR = 0.2091 for 13598 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that there are three crystallographically independent Co（II） atoms in the complex. The complex consists of binuclear coordination cation, binuclear coordination anion, as well as lattice water molecules, which further aggregate into a 3D framework via hydrogen bonding as well as π-π interactions.

Synthesis,Crystal Structure and Photophysical Property of 2-(9H-carbazol-9-yl)-3-(2-(2,4,5-tri-(9H-carbazol-9-yl)-3,6-dicyanophenoxy)phenoxy)dibenzo[b,e][1,4]dioxine-1,4-dicarbonitrile

A purely organic compound 2-（9 H-carbazol-9-yl）-3-（2-（2,4,5-tri-（9 H-carbazol-9-yl）-3,6-dicyanophenoxy）phenoxy）dibenzo[b,e][1,4]dioxine-1,4-dicarbonitrile, C76 H40 N8 O4, was synthesized and characterized by NMR, UV-Vis, photoluminescenceand X-ray single-crystal structure analysis. The compound crystallizes in monoclinic system, space group P21/n with a = 11.6537（3）, b = 34.9738（8）, c = 15.5053（3） ？, β =101.992（2）°, V = 6181.6（2）？3, Z = 4, Mr= 1129.18 g/mol, Dc =1.396 g/cm3, F（000） =2672, μ = 2.239 mm–1, GOOF = 1.019, the final R = 0.0577 and wR= 0.1559 for 11925 observed reflections with I 〉2σ（I）. The UV-vis absorption and fluorescence of the compound were discussed. The compound exhibitsyellow-green luminescence with maximum emission peak at 538 nm, and quantum yields of ф = 0.25 and 0.48 in air-equilibrated and degassed toluene at room temperature. Transient decay spectral studies show that compound 1 displays two component decay fashions with a short decay lifetime of 23 ns for the prompt fluoresce anda long decay lifetime of 3.8ms for thermally activated delayed fluorescence. In air-equilibrated toluene, only a short decay lifetime of 17 ns was observed.The experimental and computational results show thatthe emission of the compound originates from the CT excited states.

Self-assembled donor-acceptor hole contacts for inverted perovskite solar cells with an efficiency approaching 22%: The impact of anchoring groups

Self-assembled molecules(SAMs) have shown great potential in replacing bulk charge selective contact layers in high-performance perovskite solar cells(PSCs) due to their low material consumption and simple processing. Herein, we design and synthesize a series of donor-acceptor(D-A) type SAMs(MPA-BTCA, MPA-BT-BA, and MPA-BT-RA, where MPA is 4-methoxy-N-(4-methoxyphenyl)-N-phenylaniline;BT is benzo[c][1,2,5]-thiadiazole;CA is 2-cyanoacrylic acid, BA is benzoic acid, RA is rhodanine-3-propionic acid) with distinct anchoring groups, which show dramatically different properties. MPA-BTCA with CA anchoring groups exhibited stronger dipole moments and formed a homogeneous monolayer on the indium tin oxide(ITO) surface by adopting an upstanding self-assembling mode. However, the MPA-BT-RA molecules tend to aggregate severely in solid state due to the sp~3 hybridization of the carbon atom on the RA group, which is not favorable for achieving a long-range ordered self-assembled layer.Consequently, benefiting from high dipole moment, as well as dense and uniform self-assembled film,the device based on MPA-BT-CA yielded a remarkable power conversion efficiency(PCE) of 21.81%.Encouragingly, an impressive PCE approaching 20% can still be obtained for the MPA-BT-CA-based PSCs as the device area is increased to 0.80 cm^(2). Our work sheds light on the design principles for developing hole selecting SAMs, which will pave a way for realizing highly efficient, flexible, and large-area PSCs.

Synthesis,Crystal Structure and Photoluminescence of a TADF Cuprous Complex

A four-coordinate mononuclear cuprous complex oCBP-Cu-Pym(1, oCBP =1,2-bis(diphenylphosphine)-nido-carborane, Pym = 2-methyl-6-(1 H-pyrazol-1-yl)pyridine) was synthe-sized and characterized by elemental analysis, NMR, UV-Vis and X-ray single-crystal structure analysis. It crystallizes in monoclinic space group C2/c with a = 28.4182(8), b =16.2994(4), c = 22.2708(5) ?, β = 127.219(2)°, V = 8214.8(3) ?3, Z = 8, Mr = 766.92, ρcalc = 1.24 g/cm3, F(000) = 3160, μ = 2.30 mm–1, GOOF = 1.063, the final R = 0.0700 and wR = 0.1903 for7158 observed reflections with I > 2σ(I). The Cu(I) ion adopts a highly distorted tetrahedral geometry defined by two nitrogen and two phosphorous atoms. Under UV 365 nm at room temperature, this complex exhibits green emission with maximum emission peak at 516 nm,lifetime 32.4 μs and quantum yield(ф = 0.461) in the solid state. Photophysical investigation suggests that the emission of complex 1 at room temperature was attributed to TADF, which is strongly supported by theoretic calculation.

Fabrication of WO3/TiO2 Heterostructures for Efficiently Photocatalytic Gaseous Hydrocarbons Degradation:Origin of Photoactivity and Revisit the Role of WO3 Decoration

Efficient oxidation of gaseous small molecular hydrocarbons under mild conditions remains a significant but challenging task to date. Here we report that WO3 decoration can obviously improve the performance of TiO2 （P25） toward the photocatalytic oxidation of several small molecular hydrocarbons （C2H6, C3H8 and C2H4） under simulated solar light irradiation. Among the WO3/TiO2 heterostructures, the 10wt%WO3/TiO2 nanocomposite shows the best photoactivities, which can efficiently oxidize C2H6, C3H8 and C2H4 within 15, 9 and 8 minutes, respectively under simulated sunlight with a light intensity of 200 mW/cm2. By strong contrast, a decreased photoactivity of TiO2 by coupling with WO3 is observed when investigating the performance of photocatalysts toward the degradation of methylene blue （MB） in liquid phase. The opposing effect of WO3 decoration on the performance of TiO2 is thoroughly investigated, and it is found that the improved photoactivities for gaseous hydrocarbon degradation is ascribed to the enhanced oxygen adsorption, resulting from WO3 decoration rather than efficient charge separation within the WO3/TiO2 heterostructures.

Synthesis,Crystal Structure,and Photo-and Electro-luminescence of a TADF Cu(Ⅰ)Complex

A four-coordinate mononuclear cuprous complex [Cu（ac1m）POP]BF4·0.5（C6H14）· 0.5（C2H5OH）（1, ac1 m = 2-（2-ethoxyphenyl）-1-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline, POP = bis[2-（dipenylphosphino）phenyl]ether） was synthesized and characterized by elemental analysis, NMR, UV-vis, cyclic voltammetry and X-ray single-crystal structure analysis. It crystallizes in monoclinic space group P21/c with a = 17.0546（19）, b = 15.4650（17）, c = 23.685（2） A, β = 104.007（11）°, V = 6061.1（12）A^3, Z = 4, Mr = 1171.46, Dc = 1.284 g/cm^3, F（000） = 2432, μ = 1.50 mm^–1, GOOF = 1.070, the final R = 0.059 and wR = 0.1640 for 8952 observed reflections with I 〉 2σ（Ⅰ）. Compound 1 is composed of a BF4-anion and a [Cu（ac1m）POP]^＋ cation. The Cu（Ⅰ） ion adopts a tetrahedral coordination geometry defined by two nitrogen and two phosphorous atoms. The complex exhibits yellow luminescence with maximum emission peaks at 546 nm, lifetimes 15.1 μs and quantum yields（ф = 0.130） at room temperature. The complex displays thermally activated delayed fluorescence（TADF） at room temperature, which is proved experimentally and theoretically. And the organic light-emitting diode（OLED） with 1 as the light emitting material has the maximum current efficiency of 5.86 cd/A and the highest brightness of 3215 cd/m^2.

Alternative lead-free mixed-valence double perovskites for high-efficiency photovoltaic applications

Lead-based organic-inorganic hybrid perovskites have exhibited great potential in photovoltaics,achieving power conversion efficiencies(PCEs) exceeding 25%.However,the toxicity of lead and the instability of these materials under moist conditions pose significant barriers to large-scale production.To overcome these limitations,researchers have proposed mixed-valence double perovskites,where Cs_(2)Au~ⅠAu~ⅢI_6 is a particularly effective absorber due to its suitable band gap and high absorptance efficiency.To further extend the scope of these lead-free materials,we varied the trivalent gold ion and halogen anion in Cs_(2)Au~ⅠAu~ⅢI_6,resulting in 18 new structures with unique properties.Further,using first-principles calculations and elimination criteria,we identified four materials with ideal band gaps,small effective carrier mass,and strong anisotropic optical properties.According to theoretical modeling,Cs_(2)AuSbCl_6,Cs_(2)AuInCl_6,and Cs_(2)AuBiCl_6 are potential candidates for solar cell absorbers,with a spectroscopic limited maximum efficiency(SLME) of approximately 30% in a 0.25 μm-thick film.These three compounds have not been previously reported,and therefore,our work provides new insights into potential materials for solar energy conversion.We aim for this theoretical exploration of novel perovskites to guide future experiments and accelerate the development of high-performance photovoltaic devices.

Novel 2D bifunctional layered rare-earth hydroxides@GO catalyst as a functional interlayer for improved liquid-solid conversion of polysulfides in lithium-sulfur batteries

The detrimental“shuttle effect”of lithium polysulfides(LiPSs)together with sluggish multi-order reaction kinetics are the main drawbacks hindering lithium-sulfur(Li-S)batteries from commercial success.Here,we first propose the implementability of layered rare-earth hydroxides(LREHs)in Li-S batteries to optimize electrochemical performance.In this work,a two-dimensional(2D)rare-earth-based composite constructed by the layered gadolinium hydroxy chloride[Gd_(2)(OH)_(5)(H_(2)O)_(n)]Cl nanoplates(LGdH NPs)and graphene oxide(GO)was designed as a sulfur immobilizer for Li-S batteries.Combining the experimental results and density functional theory(DFT)calculations,it is revealed that the LGdH@GO composite not only provides a strong anchoring of the intermediates during cycling,but also acts as an effective catalyst to accelerate the liquid-solid conversion of polysulfides.The Li-S batteries assembled by LGdH@GO modified separators delivered a superior rate performance with a specific capacity of 605.34 mAh/g at 5 C,as well as excellent cycle stability with a decay rate of 0.087%over 500 cycles at 2 C.This study provided a deep understanding of the mechanism to suppress the“shuttle effect”by the LREHs,and a guide to design effective functional interlayers for high-performance Li-S batteries with excellent electrocatalytic activity.

Synergic catalysis of W and Ni originating from substitution of trivacant phosphotungstate for the selective oxidation of aniline to azoxybenzene

Partial substitution of polyoxometalate(POM)is an efficient route to modulate the catalytic property of maternal POM.In this work,a new Keggin type POM involving{Ni 6}cluster,{[Ni(H_(2)O)_(2)(Dach)_(2)][Ni(Dach)_(2)]_(2)}{[Ni_(6)Cl(μ-OH)_(3)(H_(2)O)(Dach)_(3)(WO_(4))(PW9 O_(3)_(4))][Ni_(6)(μ-OH)_(3)(H_(2)O)_(2)(Dach)_(3)(WO_(4))(PW9 O_(3)_(4))]}Cl·27H_(2)O,(1,Dach=1,2-diaminocyclohexane)was synthesized.Compounds 1 shows excellent catalytic performance in the selective oxidation of aniline to azoxybenzene(AOB)in water.The apparently different results from that with the matrix{PW_(9)O_(34)}({PW9})suggest the successful regulation of the catalytic property of{PW9}by the introduction of the{Ni6}cluster into the skeleton.The experimental results indicate that the highlighted performance of 1 is contributed by the synergy of W and Ni sites,which are respectively responsible for the oxidation and condensation steps in the production of AOB.The good selectivity to AOB is essentially attributed to the effective modulation of the reaction rates of oxidation and condensation steps by W and Ni sites,respectively.

A new class of crystalline X-ray induced photochromic materials assembled from anion-directed folding of a flexible cation

Electron-deficient viologens are widely used as ligands or structure-directing agents(SDAs)to synthesize crystalline X-ray induced photochromic materials.Here,a new rational strategy of anion-directed fold-ing a flexible cation(H_(2)imb)^(2+)((H_(2)imb)^(2+)=di-protonated 2,3-bis(imidazolin-2-yl)-2,3-dimethylbutane)has been developed.Electron-donating Cl−and(ZnCl4)2−are used to direct folding a flexible electron-deficient(H_(2)imb)^(2+)cation.Three complexes(H_(2)imb)(NO_(3))2(1),(H_(2)imb)Cl2·H_(2)O(2),and(H_(2)imb)ZnCl4(3)have been synthesized in which(H_(2)imb)^(2+)crystallize in an anti-conformation,88.8°-gauche,and 51.8°-gauche,respectively.In contrary to X-ray silent complex 1,X-ray induced photochromism has been achieved in both complex 2 and 3.An intermolecular charge-transfer mechanism has been elucidated and the anion directed folding of(H_(2)imb)^(2+)has been validated to be critical to yield colored long-lived charge-separated states.

From Jackfruit Rags to Hierarchical Porous N-Doped Carbon: A High-Performance Anode Material for Sodium-Ion Batteries

Renewable biomass-derived carbon materials have attracted increasing research attention as promising electrode materials for electrochemical energy storage devices, such as sodium-ion batteries (SIBs), due to their outstanding electrical conductivity, hierarchical porous structure, intrinsic heteroatom doping, and environmental friendliness. Here, we investigate the potential of hierarchical N-doped porous carbon (NPC) derived from jackfruit rags through a facile pyrolysis as an anode material for SIBs. The cycling performance of NPC at 1 A/g for 2000 cycles featured a stable reversible capacity of 122.3 mA h/g with an outstanding capacity retention of 99.1%. These excellent electrochemical properties can be attributed to the unique structure of NPC;it features hierarchical porosity with abundant carbon edge defects and large speci c surface areas. These results illuminate the potential application of jackfruit rags-derived porous carbon in SIBs.

Recent advances in non-metal doped titania for solar-driven photocatalytic/photoelectrochemical water-splitting

Photocatalytic (PC) / Photoelectrochemical (PEC) water splitting under solar light irradiation is considered as a prospective technique to support the sustainable and renewable H_(2) economy and to reach the ultime goal of carbon neutral. TiO_(2) based photocatalysts with high chemical stability and excellent photocatalytic properties have great potential for solar-to-H_(2) conversion. To conquer the challenges of the large band-gap and rapid recombination of photo generated electron-holepairs in TiO_(2), non-metal doping turns out to be economic, facile, and effective on boosting the visible light activity. The localized defect states such as oxygen vacancy and Ti^(3+) generated by non-metal doping are located in the band-gap of TiO_(2), which result in the reduction of band-gap, thus a red-shift of the absorption edge. The hetero doping atoms such as B^(3+), I^(7+), S^(4+)/S^(6+), P^(5+) can also act as electron donors or trap sites which facilitate the charge carrier separation and suppress the recombination of electron-hole pairs. In this comprehensive review, we present the most recent advances on non-metal doped TiO_(2) photocatalysts in terms of fundamental aspects, origin of visible light activity and the PC / PEC behaviours for water splitting. In particular, the characteristics of different non-metal elements (N, C, B, S, P, Halogens) as dopants are discussed in details focusing on the synthesis approaches, characterization as well as the efficiency of PC and PEC water splitting. The present review aims at guiding the readers who want quick access to helpful information about how to efficiently improve the performance of photocatalysts by simple doping strategies and could stimulate new intuitive into the new doping strategies.