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In order to meet the requirements of new renewable energy technologies for electrode materials with appropriate structural, electronic, and mechanical properties, first principles calculations were used to study the electrochemical properties and potential applications of B2S3 semiconductor optoelectronic materials with dynamic, mechanical, and thermal stability. The research results indicate that as an anode material, B2S3 monolayer has suitable storage capacity (Li: 227.2 mAh/g; Na: 340.8 mAh/g), ultra-low diffusion barrier (Li: 0.23 eV; Na: 0.14 eV), and low average open circuit voltage (Li: 0.515 eV; Na: 0.162 eV). It has relatively small lattice changes (Li: 2.5%; Na: 2.1%) during charge and discharge processes. Under different concentrations of lithium/sodium ion adsorption, the metal properties of B2S3 monolayer remain unchanged, exhibiting good conductivity and battery stability. This study indicates that B2S3 semiconductor optoelectronic material is an attractive anode candidate material for lithium/sodium ion batteries. The excellent properties of B2S3 monolayer can further explore its application as an anode material for lithium/sodium ion batteries. [ABSTRACT FROM AUTHOR]

To prevent further decomposition of organic–inorganic hybrid perovskite by defects, in this work density functional theory was applied to explore the electronic properties, carrier surface mobility and theoretical photoelectric conversion efficiency (PCE) of passivating molecules with different fluorine atom content at the symmetric site of the benzene ring at different termination ends of MAPbI3, which shed light on the control of perovskite surface passivation by different element atoms in the same molecule. We found that the same molecule acts as a different passivation agent at different termination faces. Passivating molecules on the surface termination end by MAI play a Lewis acid role, with molecules with stronger dipole moments narrowing the band gap from the original 1.77 to 1.73 eV. The exciton binding energy of molecules with stronger dipole moments (0.187–0.292 meV) is significantly lower than that of MAPbI3 (0.332 meV), so the effective separation of interface electrons and holes can be realized. Bromopenta-fluorobenzene has a lower adsorption energy of −0.17 eV, which can stably adsorb on the surface of perovskite and increase visible light absorption. Ultimately, the theoretical PCE increased from 15.8% to 16.16%. In addition, on the surface terminated by PbI2, BrB with a strong dipole moment can provide electrons for Pb2+ and act as a Lewis base. At the surface end, it can form an ionic bond with Pb2+, while the antibonding molecular orbital characteristic is dominant, which increases the band gap from 1.76 to 1.87 eV. After increasing to 4-F-BrB, the fluorine atom has strong electronegativity and can easily bond with Pb2+. The conjugate π cycle intensifies the promotion of electron transfer, reducing the work function from 5.262 to 4.703 eV, reducing the effective electron and hole mass (0.514, 0.204 m0), and improving the photovoltaic performance. Finally, increasing the number of passivation molecules resulted in a decrease in the PCE from 15.93% to 14.75%. [ABSTRACT FROM AUTHOR]

To prevent further decomposition of organic-inorganic hybrid perovskite by defects, in this work density functional theory was applied to explore the electronic properties, carrier surface mobility and theoretical photoelectric conversion efficiency (PCE) of passivating molecules with different fluorine atom content at the symmetric site of the benzene ring at different termination ends of MAPbI 3 , which shed light on the control of perovskite surface passivation by different element atoms in the same molecule. We found that the same molecule acts as a different passivation agent at different termination faces. Passivating molecules on the surface termination end by MAI play a Lewis acid role, with molecules with stronger dipole moments narrowing the band gap from the original 1.77 to 1.73 eV. The exciton binding energy of molecules with stronger dipole moments (0.187-0.292 meV) is significantly lower than that of MAPbI 3 (0.332 meV), so the effective separation of interface electrons and holes can be realized. Bromopenta-fluorobenzene has a lower adsorption energy of -0.17 eV, which can stably adsorb on the surface of perovskite and increase visible light absorption. Ultimately, the theoretical PCE increased from 15.8% to 16.16%. In addition, on the surface terminated by PbI 2 , BrB with a strong dipole moment can provide electrons for Pb 2+ and act as a Lewis base. At the surface end, it can form an ionic bond with Pb 2+ , while the antibonding molecular orbital characteristic is dominant, which increases the band gap from 1.76 to 1.87 eV. After increasing to 4-F-BrB, the fluorine atom has strong electronegativity and can easily bond with Pb 2+ . The conjugate π cycle intensifies the promotion of electron transfer, reducing the work function from 5.262 to 4.703 eV, reducing the effective electron and hole mass (0.514, 0.204 m 0 ), and improving the photovoltaic performance. Finally, increasing the number of passivation molecules resulted in a decrease in the PCE from 15.93% to 14.75%.