In this work, oxygen-doped g-C3N4 mesoporous nanosheets (O-CNS) were synthesized via a facile recrystallization method with the assistance of H2O2. The crystal phase, chemical composition, morphological structure, optical property, electronic structure and electrochemical property of the prepared O-CNS samples were well investigated. The morphological observation combining with nitrogen adsorption-desorption results demonstrated that the prepared O-CNS samples possessed nanosheets-like morphology with porous structure. The O doping into g-C3N4 resulted in the augment of specific surface area, which could provide more active sites for photocatalytic reaction. Simultaneously, the visible-light absorption capacity of O-CNS samples was boosted owing to the regulation of O doping. The built energy level induced by the O doping could accelerate the migration rate of photoinduced carriers, and the porous structure was most likely to speed up the release of hydrogen during photocatalyic hydrogen process. Resultantly, the photocatalytic hydrogen production rate of the optimized oxygen-doped g-C3N4 nanosheets reached up to 2012.9 μmol•h-1•g-1, which was 13.4 times higher than that of bulk g-C3N4. Thus, the significantly improved photocatalytic behavior was imputed to the porous structure, the augment of active sites, and the enhancement of visible light absorption and charge separation efficiency.

Rice blast and brown planthopper (BPH) are two of the most destructive diseases and pests in rice (Oryza sativa L.) production in China. The development of multi-resistant varieties is widely recognized as the most efficient and environmentally friendly approach to controlling crop diseases and pests. Functional molecular markers (FMMs) have been developed from functional variants in the genic region associated with trait variation, greatly enhancing the efficiency of identifying and pyramiding valuable genes in crop breeding. In this study, two FMMs and a multiplex PCR amplification system were developed for two major broad-spectrum BPH resistance genes, Bph6 and Bph9. By assistance of FMMs in multi-resistant rice restorer line development pipeline, two lines (Huahui7713 and Huahui3006) with blast and BPH resistance were developed by pyramiding three resistance genes Pigm, Bph6 and Bph9. Huahui7713 and Huahui3006 as male lines, two new hybrid rice varieties (WeiLiangYou7713 and Xuanliangyou3006) were certificated and commercial released in China. WeiLiangYou7713 and Xuanliangyou3006 showed improved blast and BPH resistance, and no penalty on yield and grain-quality. Annual promotion area of WeiLiangYou7713 has exceeded 53.3 thousand hectares, indicating its widespread adoption and success in the market. Huahui7713 and Huahui3006 could have great potential for utilization in blast and BPH resistance rice breeding.