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碳点衍生的碳纳米花负载钴单原子和纳米颗粒用于高效的氧还原反应

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Chinese j.urnal of Catalysis 2022年第9期43卷 2443-2452页

作者：程瑶佳宋昊强于镜坤常江伟 Geoffrey INwaterhouse 唐智勇杨柏卢思宇郑州大学化学学院绿色催化中心中国河南郑州450000 吉首大学化学与化工学院中国湖南吉首416000 奥克兰大学化学科技学院新西兰奥克兰1142 中国科学院国家纳米科学技术中心纳米系统与多级制备中科院重点实验室中国北京100190 吉林大学化学学院超分子结构与材料化学学院国家重点实验室中国吉林长春130012

锌空气电池(ZABs)具有高能量密度(1086 mWh gZn^(–1))、价低、易回收等优势,引起了学者们的广泛关注.空气电极发生的氧还原反应(ORR)/氧析出反应(OER)是控制整个ZABs效率的关键.因此,设计和开发高效的ORR电催化剂对于ZABs商业化至关重... 详细信息

锌空气电池(ZABs)具有高能量密度(1086 mWh gZn^(–1))、价低、易回收等优势,引起了学者们的广泛关注.空气电极发生的氧还原反应(ORR)/氧析出反应(OER)是控制整个ZABs效率的关键.因此,设计和开发高效的ORR电催化剂对于ZABs商业化至关重要.目前,Pt基电催化剂仍是最有效的ORR电催化剂,但Pt资源稀缺,价格高昂,Pt基电催化剂稳定性差等缺点阻碍了其商业化.因此,研究高活性和高稳定性的ORR非贵金属电催化剂十分重要.碳点(CDs)作为一种新型的零维高分子碳材料,具有低毒、高导电性等优势,被广泛用于碳基材料的前驱体.CDs具有sp^(2)杂化晶核、丰富的边缘位点和大量的官能团(如‒NH_(2),‒COOH和‒OH),这些表面官能团为过渡金属原子提供了很强的锚定位点,可用于构筑各种碳负载过渡金属催化剂.本文设计合成了一种新型的碳基ORR电催化剂,其由CDs衍生的三维碳纳米花(CNF)负载Co单原子(SAs)和纳米颗粒(NPs)构成.利用CDs在二次水热过程中形成了3.66 nm的超薄纳米膜并构筑成3D的多孔CNF结构.X射线衍射、高角度环形暗场原子分辨率扫描跃迁电子显微镜和X射线吸收光谱结果表明,材料中的SAs和NPs共存.测试结果表明,Co SAs/NPs CNF拥有可以和商业Pt/C相当的ORR活性(E_(1/2)=0.83 V(vs.RHE),j.(L)=6.13 mA cm^(-2)),且具有良好的稳定性.同时,利用SCN–可以毒化SAs和NPs,而EDTA只能毒化SAs的特性,证明了Co SAs和Co NPs协同促进了整个催化反应过程.理论计算表明,相邻Co NPs的存在优化了Co-N_(4)位点的电子结构,显著降低了ORR决速步骤(*OOH吸附)的能垒.因此,在整个催化反应过程中,Co SAs和Co NPs协同改善了ORR过程中的电子和质子转移行为.Co SAs/NPs CNF较大的比表面积和丰富的多孔结构有利于O_(2)和质子传输,基于其组装的ZABs的能量密度高达1000.58 mWh gZn^(–1)(理论值的93.69%)和循环运行1300次性能依然稳定.综上,本工作为高性能ORR电催化剂的设计提供依据.

关键词：碳点钴单原子钴纳米颗粒氧还原反应锌空电池

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Highly Efficient Photoelectrocatalytic Reduction of CO2 to Methanol by a p–n Heteroj.nction CeO2/CuO/Cu Catalyst

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Nano-Micro Letters 2020年第2期12卷 34-46页

作者： Zhengbin Pan Ershuan Han j.ngui Zheng j.ng Lu Xiaolin Wang Yanbin Yin Geoffrey INwaterhouse Xiuguo Wang Peiqiang Li Tobacco Research Institute of Chinese Academy of Agricultural Sciences(CAAS) Qingdao 266101People’s Republic of China College of Chemistry and Material Science Shandong Agricultural UniversityTai’an271018People’s Republic of China School of Chemical Sciences The University of AucklandAuckland 1142New Zealand

Photoelectrocatalytic reduction of CO2 to fuels has great potential for reducing anthropogenic CO2 emissions and also lessening our dependence on fossil fuel energy.Herein,we report the successful development of a novel photoelectrocatalytic catalyst for the selective reduction of CO2 to methanol,comprising a copper catalyst modified with flower-like cerium oxide nanoparticles(CeO2 NPs)(a n-type semiconductor)and copper oxide nanoparticles(CuO NPs)(a p-type semiconductor).At an applied potential of−1.0 V(vs SCE)under visible light irradiation,the CeO2 NPs/CuO NPs/Cu catalyst yielded methanol at a rate of 3.44μmol cm^−2 h^−1,which was approximately five times higher than that of a CuO NPs/Cu catalyst(0.67μmol cm^−2 h^−1).The carrier concentration increased by^108 times when the flower-like CeO2 NPs were deposited on the CuO NPs/Cu catalyst,due to synergistic transfer of photoexcited electrons from the conduction band of CuO to that of CeO2,which enhanced both photocatalytic and photoelectrocatalytic CO2 reduction on the CeO2 NPs.The facile migration of photoexcited electrons and holes across the p–n heteroj.nction that formed between the CeO2 and CuO components was thus critical to excellent light-induced CO2 reduction properties of the CeO2 NPs/CuO NPs/Cu catalyst.Results encourage the wider application of composite semiconductor electrodes in carbon dioxide reduction.

关键词： CO2 reduction Photoelectrocatalysis p–n heteroj.nction Cerium oxide Copper oxide

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母亲妊娠期间的因素能否影响到出生后10年内子女的哮喘表现型

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世界核心医学期刊文摘（儿科学分册） 2005年第9期1卷 54-55页

作者： Kurukulaaratchy R.j. waterhouse L. Matthews S.M. ArshadS.H. 李开 Department of Respiratory Medicine University Hospital of North Staffordshire Newcastle Road Stoke-on-Trent ST4 6QG United Kingdom

Aim: Recently, attention has focused on possible early life origins for asthma. We sought to identify whether factors present during pregnancy were associated with development of childhood wheezing phenotypes. Methods: A whole populationbirth cohort (n=1456) on the Isle of Wight, UK, was followed through to age 10 y. Where possible, information regarding environmental exposures and events during pregnancy was obtained from the maternity records (n=1238). Children were seen at ages 1, 2, 4 and 10 y, and wheezing symptoms were used to define wheezing phenotypes in the first decade (n=1034). Results: Risk of early-onset persistent wheeze (onset in the first 4 y, still present at age 10) was increased by environmental tobacco smoke exposure in pregnancy (OR=2.44;95% CI: 1.37-4.34) plus maternal asthma (3.57; 1.84-6.94), but reduced by cat ownership (0.30; 0.13-0.62). Early transient wheeze (onset in the first 4 y, but not present at age 10) was increased by environmental tobacco smoke exposure (1.58; 1.02-2.45),male gender (1.68; 1.09-2.60) and low birthweight (3.65; 1.27-10.52). No environmental factors in pregnancy were associated with lateonset persistent wheeze (onset after age 4 y, still present at 10 y). Conclusion: In addition to genetics, maternal exposures during pregnancy show association with childhood and especially early-life wheezing phenotypes.

关键词：母亲妊娠期表现型出生后出生婴儿早发性环境暴露发病风险早期胚胎发育怀特岛事件信息

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结核胸片影像参考系统对非专业人士阅片的影响

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国际医学放射学杂志 2013年第6期 595-595页

作者： C.j.Waitt E.C.j.ekes N.j.sudason P.I.Waitt P.Goodson G.Likumbo 彭景刘静 Department of Pharmacology University of Liverpool2nd Floor Block A: Waterhouse Buildings 1-5 Brownlow StreetLiverpool L69 3GL UK

摘要目的在欠发达的地区,肺结核(PTB)胸部X线检查(CXR)诊断的准确性与非专业人士的阅片能力部分相关。设计了一种TB CXR影像参考系统(TB CXR Image Reference

关键词：放射学结核马拉维敏感度和特异度教学