A novel photocatalytic water splitting solar-to-hydrogen energy conversion: Non-centro-symmetric borate CsZn2B3O7 photocatalyst

The photocatalytic performance of the novel borate CsZn2B3O7 is theoretically investigated by means of density functional theory. The calculation highlights that the packing of the BO3 structural unit is the main source for the large macroscopic photophysical properties in CsZn2B3O7 due to high anisotropic electron distribution. The potentials of the conduction band (CB) and valence band (VB) edges values of CsZn2B3O7 are -1.789 eV and 3.891 eV, respectively. The CB edge potential of CsZn2B3O7 is more negative than the redox potential of H+/H-2, indicating that the CsZn2B3O7 has strong reduction power for H-2 production. The absorption edge of CsZn2B3O7 occurs at l = 218 nm and the optical band gap is estimated to be 5.68 eV, in good agreement with the experimental data (5.69 eV). Therefore, CsZn2B3O7 expected to be an efficient photocatalyst in the ultraviolet (UV) region. Thus, CsZn2B3O7 possesses an appropriate band gap width and suitable CB edge position together, which leads to a higher efficiency of light-driven photocatalytic H-2 production. Also, it possesses high photogenerated carrier mobility and high electronic conductivity, which favors the enhancement of the photocatalytic performance. The large photocatalytic performance is due to the strong interactions between the ZnO4 tetrahedra and co-parallel BO3 triangle groups. In this study we provide a detailed investigation concerning the suitability of CsZn2B3O7 to be used as an efficient photocatalyst under UV irradiation utilizing the first- principle material approaches, which greatly improves the search efficiency and greatly helps experiments to save resources in the exploration of new photocatalysts with good photocatalytic performance. (C) 2018 Elsevier B.V. All rights reserved

Spin-polarized antiferromagnetic CaCoSO single crystal: First principles study

Komplexní spin-polarizované výpočty byly provedeny pro nedávno syntetizovaný antiferromagnetický CaCoSO monokrystal založený na metodě full-potential plus Hubbard Hamiltonian. Experimentální mřížkové parametry monokrystalu CaCoSO byly optimalizovány a pokusné atomové polohy byly uvolněny tak, aby se minimalizovaly sílypůsobící na atomyComprehensive spin-polarized calculations were performed for the recently synthesized antiferromagnetic CaCoSO single crystal based on the full-potential method plus Hubbard Hamiltonian. The experimental lattice parameters of the CaCoSO single crystal were optimized and the experimental atomic positions were relaxed so as to minimize the forces acting on the atom

Sulfide Oxide XZnSO (X =Ca or Sr) as Novel Active Photocatalytic Water Splitting Solar-to-Hydrogen Energy Conversion

Fotokatalytické, strukturní a transportní vlastnosti nově syntetizovaného sulfidu oxidu CaZnSO a SrZnSO jsou komplexně zkoumány výpočtem prvního a druhého principu za účelem vysvětlení "fotoexcitace" polovodičů, mechanismus stavu v CaZnSO a SrZnSO.The photocatalytic, structural and transport properties of the newly synthesized sulfide oxide CaZnSO and SrZnSO compounds are comprehensively investigated by means of first and second-principles calculation in order to explain the semiconductor's 'photoexcitation' state mechanism in CaZnSO and SrZnSO

Exploring the electronic structure of Pb2 ions containing material Pb-16(OH)(16)(NO3)(16)

Výpočet teoretické pásové struktury monokrystalu nitratehydroxidu olova Pb16 (OH) 16 (NO 3) 16 byl proveden na základě experimentálních krystalografických dat získaných záměnou. Výpočty vykazují, že mimum (CBM), se nachází v Γ středu Brillouin zóny (BZ), zatímco skupina valence maximua (VBM) se nachází mezi Γ a Y bodů BZA theoretical band structure calculation for lead nitratehydroxide Pb16(OH)16(NO3)16 single crystal was performed based on the experimental crystallographic data obtained by Changetal. Calculations exhibit that the conduction bandminimum (CBM) is situated at Γ the center of the Brillouin zone (BZ) while the valence band maximum (VBM) is located between Γ and Y points of the B

Photophysical, transport and structure properties of Tl10Hg3Cl16 single crystals: Novel photocatalytic water-splitting solar-to-hydrogen energy conversion

Abstrakt k výsledku česky: Fotokatalytické, transportní, fotofyzikální a strukturní vlastnosti jednotlivých monokrystalů Tl10Hg3Cl16 se zkoumají pomocí teorie funkční hustoty, aby se prozkoumala jejich vhodnost pro použití jako aktivní fotokatalyzátorThe photocatalytic, transport, photophysical, and structural properties of Tl10Hg3Cl16 single crystals are investigated by means of density functional theory in order to investigate its suitability to be used as an active photocatalys

Novel borate CsZn2B3O7 single crystal with large efficient second harmonic generation in deep-ultraviolet spectral range

Lineární a nelineární optická susceptibilita disperze CsZn2B3O7 monokrystalu je komplexně zkoumána na objemovou strukturu ve formě monokrystalu s ohledem na vliv balení strukturních jednotek.The linear and nonlinear optical susceptibility dispersion of CsZn2B3O7 single crystal are comprehensively investigated for a bulk structure in form of single crystal taking into account the influence of the packing structural units

Active photocatalytic water splitting solar-to-hydrogen energy conversion: Chalcogenide photocatalyst Ba2ZnSe3 under visible irradiation

Fotokatalytický výkon Ba2ZnSe3 je zkoumán teorií funkční hustoty. Zkoumání potvrzuje, že Ba2ZnSe3 vykazuje velkou birefringenci, značnou anizotropii v optické odezvě a absorpční okraj ve viditelné oblasti.The photocatalytic performance of Ba2ZnSe3 is investigated by means of density functional theory. The investigation confirms that Ba2ZnSe3 possesses large birefringence, considerable anisotropy in the optical response, and the absorption edge occurs in the visible region

Revealing the transport properties of the spin-polarized b0 -Tb2(MoO4)3: DFT U

Termoelektrické vlastnosti polarizované spin-polarizované b0-Tb2(MoO4)3 fáze se vypočítají pomocí prvních principů a druhých principů metod pro řešení poloklasických transportních rovnic Bloch-Boltzmann. Je zajímavé zdůraznit, že vypočtená elektronická struktura pásma odhalila, že b0-Tb2(MoO4)3 má parabolické pásy v blízkosti úrovně Fermi (EF).The thermoelectric properties of the spin-polarized b0-Tb2(MoO4)3 phase are calculated using first-principles and second-principles methods to solve the semi-classical Bloch-Boltzmann transport equations. It is interesting to highlight that the calculated electronic band structure reveals that the b0-Tb2(MoO4)3 has parabolic bands in the vicinity of the Fermi level (EF)

Thermoelectric properties of highly-mismatched alloys of GaNxAs1-x from first- to second-principles methods: energy conversion

V transportní vlastnosti GaNxAs1_x (x ¼ 0.0, 0.25 0.5, 0.75 a 1.0) slitiny jsou studovány za použití semi-klasické teorie Boltzmann což je provedeno v BoltzTraP kódu. Elektronické struktury jsou vypočítány s metodou the full potential linearized augmented plane wave method within the recently modified Becke-Johnson potential,která řeší výměnu korelačního potenciálu.The transport properties of GaNxAs1_x (x ¼ 0.0, 0.25, 0.5, 0.75 and 1.0) alloys are investigated using the semi-classical Boltzmann theory as implemented in the BoltzTraP code. The electronic structures are calculated using the full potential linearized augmented plane wave method within the recently modified Becke-Johnson potential to solve the exchange correlation potential

Electronic structure and optical properties of b-RbSm(MoO4)2 from spin polarization calculations: DFTþU

Prozkoumali jsme vliv začlenění spinové polarizace na mezery energetického pásma bRbSm (MoO4) 2. Výpočty prozkoumaly, že vzhled Sm-4f udává v minimálním vedení (CBM) spin-up případu významný vliv na vlastnosti půdního stavu b-RbSm (MoO4) 2.We explored the influence of the inclusion of spin polarization on the energy band gap of bRbSm(MoO4)2. Calculations explored that the appearance of Sm-4f states at the conduction band minimum (CBM) of the spin-up case causes a significant influence on ground state properties of b- RbSm(MoO4)2