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Despite its considerable potential to address energy and environmental challenges, the practical application of photocatalysis is restricted by the limited efficiency of the photocatalysts. This research aims to improve the photocatalytic efficiency of Bi2MoO6 by adjusting the internal electric field within the crystal lattice via Te doping. Te-Bi2MoO6 nanosheets were prepared by a one-step hydrothermal method. Although the band gap energy and the long-range crystal structure are not affected upon doping, Te substitution provides several benefits to the performance of Bi2MoO6. First, the introduction of Te significantly reduces the thickness of the nanosheets, resulting in a larger surface area. Te states are also introduced into the conduction band, thereby increasing the carrier mobility. More importantly, the reduced cell parameters upon doping and the presence of Te in the lattice not only increase the potential difference between Bi–O and Mo-(Te)–O layers in the lattice but also create an asymmetric potential difference. As a result, an internal electric field is enlarged, leading to increased carrier separation. Consequently, 5.0 mol % Te-doped Bi2MoO6 could degrade 99.7% of Rhodamine B in 1 h under visible light, with 6.4 times higher rate constant than pristine Bi2MoO6. Additionally, the doped sample also exhibits about two times enhancement in benzylamine photooxidation (85% conversion vs 39% conversion) while maintaining excellent stability. Thus, this research highlights the efficacy of modulating the internal electric field through chemical modification as a viable strategy for enhancing the performance of photocatalysts. [ABSTRACT FROM AUTHOR]

Sugarcane bagasse ash (SCBA) is a solid waste containing a high amount of silica (SiO 2 ) and is suitable to utilize as a silica source for synthesizing zeolite NaA. SCBA is typically calcined at high temperatures before silica extraction. The method is not environmentally friendly because it consumes energy and produces CO 2 . This work demonstrates an alternative extraction method of SiO 2 from SCBA by treating it with hydrochloric (HCl) and sodium hydroxide (NaOH) solution. The obtained mixture was separated by paper filter No. 1 (P) and a combination of paper filter and syringe filter (PS). The solution was neutralized by HCl solution, producing silica (SiO 2 -P and SiO 2 -PS) with a purity of 98 wt%. Both SiO 2 samples and SCBA were utilized to synthesize zeolite NaA for CO 2 adsorption. The CO 2 adsorption capacities of NaA-P and NaA-PS were 4.30 and 4.10 mmol g adsorbent -1 , in the same range as commercial NaA. The capacity is influenced by the total basicity of zeolite. The CO 2 adsorption behavior of all samples correlates well with the Toth model. The CO 2 adsorption kinetics agrees well with the pseudo-second-order kinetic model. Overall, this work shows the successful extraction of silica via using a direct NaOH solution, yielding high-purity silica sufficient for synthesizing zeolite NaA, a promising adsorbent of CO 2 ., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)