Bi1−xLaxCuSeO as New Tunable Full Solar Light Active Photocatalysts

Abstract

Photocatalysis is attracting enormous interest driven by the great promise of addressing current energy and environmental crises by converting solar light directly into chemical energy. However, efficiently harvesting solar energy for photocatalysis remains a pressing challenge, and the charge kinetics and mechanism of the photocatalytic process is far from being well understood. Here we report a new full solar spectrum driven photocatalyst in the system of a layered oxyselenide BiCuSeO with good photocatalytic activity for degradation of organic pollutants and chemical stability under light irradiation, and the photocatalytic performance of BiCuSeO can be further improved by band gap engineering with introduction of La. Our measurements and density-functional-theory calculations reveal that the effective mass and mobility of the carriers in BiCuSeO can be tuned by the La-doping, which are responsible for the tunable photocatalytic activity. Our findings may offer new perspectives for understanding the mechanism of photocatalysis through modulating the charge mobility and the effective mass of carriers and provide a guidance for designing efficient photocatalyts.

One-Pot Synthesis of BiCuSO Nanosheets under Ambient Atmosphere as Broadband Spectrum Photocatalyst

“…The effective separations of photo induced holes and electrons is one of the key factors influence the photocatalytic efficiency [29,30]. According to our previous study, the different charge mobility and the effective mass of carriers play important roles in the full spectrum light response ability of BiCuSO nanosheets [20]. However, there was another possibility that the defects can trap holes and electrons and act as reaction sites, which increased the light conversion ability [31,32].…”

“…The work electrode was prepared as follow: BiCuSO powder was dispersed in glycol ethylene and stirred for 12 h. Then the slurry was coated onto FTO by doctor blade technology. After being dried at 70 °C for 12 h, the substrate was treated at 250 °C for 2 h in air [20]. The photocurrents of the BiCuSO photoanode under UV, visible and NIR lights irradiation were recorded at a bias of 0 V versus the reference electrode using back irradiation model.…”

Bismuth Oxysulfide and Its Polymer Nanocomposites for Efficient Purification

“…However, increased efficiencies of capturing and degrading contaminants is usually achieved at the cost of the structural imperfections caused by high loadings of ceramic nanoparticles [ 16 , 17 ]. With higher loading, the larger diameter of the nanofibers will results in decreased air permeability [ 18 ]. Choosing the ceramic nanoparticles doped in the polymer that form more polar bonds with the polymer matrix can enhance the electric potential differences between the nanoparticles and the polymer and therefore promote the contaminant capture capability [ 19 ].…”

Ab initio assessment of Bi1−xRExCuOS (RE = La, Gd, Y, Lu) solid solutions as a semiconductor for photochemical water splitting

“…It appears that by a small RE doping, the low bandgap of these compounds is preserved but the mobilities of charge carriers are improved, as observed experimentally for La doped BiCuOSe. 58,59 To achieve materials having a bandgap in the range 1.6-2.4 eV, therefor interesting for water splitting, the dopant concentration must be around 50%. At this concentration, the effective masses and exciton binding energies are notably increased meaning that, to obtain efficient water splitting photocatalysts with these materials a bulk heterojunction architecture must be used.…”

“…Although La doped BiCuOS was never investigated experimentally, the La doping of the parent compound BiCuOSe was the subject of two publications. 58,59 The authors of these works incorporated La atoms in BiCuOSe up to 12.5% that …”