An efficient Z-scheme (Cr, B) codoped g-C3N4/BiVO4 photocatalyst for water splitting: A hybrid DFT study

We study oxygen vacancies in the tetragonal scheelite phase of bismuth vanadate and identify stable oxygen-deficient structures. Upon subjecting these to variable-cell optimization, we find that oxygen vacancies give rise to significant structural distortions, the degree of which exhibits a vacancy concentration dependence. Furthermore, we show that these distortions give rise to splitting of powder X-ray diffraction peaks, yielding patterns similar to that of the monoclinic scheelite phase, and that these effects are also present at finite temperatures. Our results highlight the need for characterization methods beyond X-ray diffraction for identifying the phase of synthesized bismuth vanadate samples and the importance of oxygen partial pressure control during synthesis.

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Influence of Oxygen Vacancies on the Structure of BiVO4

Photoelectrochemical (PEC) technology for water splitting has been regarded as one of the most appealing and environmentally friendly approaches to converting light energy into hydrogen energy. The semiconductor material used as the photoelectrode is considered to be the most important factor affecting the efficiency of the PEC system. Bismuth vanadate (BiVO4), as a n-type semiconductor material, has a wide light absorption range, strong catalytic ability, high stability, and low cost, which makes it one of the most promising candidates as a photoanode material for PEC water splitting. Since the first report of BiVO4, tremendous efforts have been devoted to exploring different strategies for the synthesis and structural modification of BiVO4 to enhance its PEC performance, which has led to remarkable progress in recent years. This review attempts to summarize such considerable progress of BiVO4 for PEC water splitting, mainly focusing on the synthetic methods and modification strategies. In the end, the personal perspectives on the challenges and opportunities of this promising material are proposed. 

Visible Light Photoanode Material for Photoelectrochemical Water Splitting: A Review of Bismuth Vanadate

Advanced aqueous proton batteries: working mechanism, key materials, challenges and prospects

Design, fabrication and characterization of photocatalyst Ni-doped BiVO4 for high effectively degrading dye contaminant

Influences of vacancies on the structural, electronic and optical properties of monoclinic BiVO4

Regulating the electrolyte ion types and exposed crystal facets for pseudocapacitive energy storage of transition metal nitrides

A Micron-Size Carbon-Free K3V2O2(PO4)2F Cathode with High-Rate Performance for Potassium-Ion Batteries

Perovskite materials can store charge through rapid oxygen anions intercalation. Although numerous perovskite materials owing to rich selections of A and B‐site elements are reported as electrodes of supercapatteries, the effect of the crystal structure of perovskite materials on their electrochemical performance has never been studied so far. Herein, using SrCo0.9Mo0.1O3−δ, SrFeO3−δ, Ba0.5Sr0.5Co0.8Fe0.2O3−δ, and LaMnO3−δ as research targets, it is proved that their corresponding cubic structure materials display the best electrochemical performance. And then, the origin of such superiority of cubic structure for SrCo0.9Mo0.1O3−δ is explored through experimental investigations and theoretical calculations. The results show that the increase in the content of oxygen vacancies and the enhancement of B‐O hybridization of cubic structure can optimize the electronic structure of the perovskite materials, thereby improving its conductivity and accelerating the reaction kinetics. The filtering strategy based on crystal structure proposed by this report will provide a new perspective to faster and more efficient choice of perovskite materials for supercapatteries.

Xiaqing Zhang

Papers

Influences of vacancies on the structural, electronic and optical properties of monoclinic BiVO4

Regulating the electrolyte ion types and exposed crystal facets for pseudocapacitive energy storage of transition metal nitrides

A Micron-Size Carbon-Free K3V2O2(PO4)2F Cathode with High-Rate Performance for Potassium-Ion Batteries

Superiority of Cubic Perovskites Oxides with Strong B‐O Hybridization for Oxygen‐Anion Intercalation Pseudocapacitance

The influences of Nb and N dopants on elastic, electronic and optical properties of monoclinic BiVO 4