Utilizing sunlight to convert CO_(2) into chemical fuels could address the greenhouse effect and fossil fuel crisis,Heterojunction structure catalysts with oxygen vacancy are attractive in the field of photocatalytic ...Utilizing sunlight to convert CO_(2) into chemical fuels could address the greenhouse effect and fossil fuel crisis,Heterojunction structure catalysts with oxygen vacancy are attractive in the field of photocatalytic CO_(2) conversion.Herein,a modified TiO_(2)/In_(2)O_(3)(R-P2 5/In_(2)O_(3-x)) type Ⅱ heterojunction composite with oxygen vacancies is designed for photocatalytic CO_(2) reduction,which exhibits excellent CO_(2) reduction activity,with a C_(2) selectivity of 56.66%(in terms of R_(electron)).In situ Fourier-transform infrared spectroscopy(DRIFTS) and time-resolved photoluminescence(TR-PL) spectroscopy are used to reveal the intermediate formation of the photocatalytic mechanism and photogenerated electron lifetime,respectively.The experimental characterizations reveal that the R-P25/In_(2)O_(3-x) composite shows a remarkable behavior for coupling C-C bonds.Besides,efficient charge separation contributes to the improved CO_(2) conversion performance of photocatalysts.This work introduces a type Ⅱ heterojunction composite photocatalyst,which promotes understanding the CO_(2) reduction mechanisms on heterojunction composites and is valuable for the development of photocatalysts.展开更多
基金National Research Foundation (NRF) of Korea grant funded by the Korea Government (MSIT) (NRF-2022R1A2C2093415)partially funding from the Circle Foundation (Republic of Korea) (Grant Number: 2023 TCF Innovative Science Project-03))partially Korea Basic Science Institute (National Research Facilities and Equipment Center) grant funded by the Ministry of Education (2022R1A6C101A751)。
文摘Utilizing sunlight to convert CO_(2) into chemical fuels could address the greenhouse effect and fossil fuel crisis,Heterojunction structure catalysts with oxygen vacancy are attractive in the field of photocatalytic CO_(2) conversion.Herein,a modified TiO_(2)/In_(2)O_(3)(R-P2 5/In_(2)O_(3-x)) type Ⅱ heterojunction composite with oxygen vacancies is designed for photocatalytic CO_(2) reduction,which exhibits excellent CO_(2) reduction activity,with a C_(2) selectivity of 56.66%(in terms of R_(electron)).In situ Fourier-transform infrared spectroscopy(DRIFTS) and time-resolved photoluminescence(TR-PL) spectroscopy are used to reveal the intermediate formation of the photocatalytic mechanism and photogenerated electron lifetime,respectively.The experimental characterizations reveal that the R-P25/In_(2)O_(3-x) composite shows a remarkable behavior for coupling C-C bonds.Besides,efficient charge separation contributes to the improved CO_(2) conversion performance of photocatalysts.This work introduces a type Ⅱ heterojunction composite photocatalyst,which promotes understanding the CO_(2) reduction mechanisms on heterojunction composites and is valuable for the development of photocatalysts.
文摘点云分类与分割在机器人导航、虚拟现实以及自动驾驶领域应用广泛,大多面向点云处理的深度学习方法采用共享权重的多层感知机(MultiLayer Perceptron,MLP)以及单一的池化来聚合点云的局部特征,难以准确地描述排列复杂的点云结构信息。针对上述问题,提出一种点云形状自适应的局部特征编码方法,以有效表征形状多样的点云结构信息,提升点云分类和分割性能。该方法首先引入一种自适应特征增强模块,采用差分和可学习的调节因子对特征进行增强,弥补共享权重MLP描述能力不足的问题。在此基础上,设计了一种特征聚合模块,利用点云的绝对空间距离赋予不同点不同权重以适应形状多变的点云结构信息,突出有代表性的点集,更加准确地描述点云的局部结构信息。在3个大型公开点云数据集上进行实验,结果表明,在ModelNet40数据集上取得了93.9%的总体实例分类精度,在分割数据集ShapeNet和S3dis上分别取得了85.9%,59.7%的总体实例平均交并比(mean Intersection over Union,mIoU),本文提出的方法在点云分类和分割任务上表现优秀。
