?!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
偶基光热燃料(PTMQ被认ؓ是太阌热燃料@环利用领域关键的材料之一Q尤其是在低温环境中Q因为它们具有在低温下长旉储存的能力、可控的热量释放Q化学成分稳定等优势?/span>PTM的储热能量密度是其低温应用的基础Q其储存潜热的能力(能量密度Q?/span>EDQ主要取决于反异构体之间的能差(ΔEQ和异构化程度(DIQ。因此,在分子尺度上Q优化能U和异构化动力学对于提高PTM的能量密度非帔R要?/span>目前Q由于自w分子结构的限制Q导致偶氮基光热燃料分子能量密度低且攄温度高,使其在低温环境应用领域面临巨大的挑战?/span>
配位键在特定条g下(如光Q力{)可以断开q复原,q种键的性质被广泛用来构{各U响应性材料和自修复材料?/span>q日Q天z大学封伟教授团队提出制备了一pd配位键调控偶氮苯化合?/span>-矛_烯杂化材料,发现配位键键能可以和光热能同时进行存储和释放Q得所制备的光热材料的能量密度大大提高Q?/span>720 J g-1Q?/span>q一步构Z可在低温下运行的能量循环利用pȝ。该工作在分子设计的基上,合成了具有磺酸基团的偶苯化合物-矛_烯杂化材料(G-AzoQ,随后引入配位键将G-Azoq接Q制备得C光响应偶氮苯化合?/span>-矛_?/span>-金属配位杂化材料Q?/span>G-Azo-MQ?/span>配位键的引入提高?/span>G-Azo反异构体之间的能差,q而大大提高了其能量密度,实现了光热能和键能在低温下的存储和可控利用?/span>当外光照射ӞG-Azo发生反式-式异构化,配位键断开Q储存光热能和键能;当可见光照射ӞG-Azo发生式-反式异构化,配位键再ơ自发Ş成,同时释放光热能和键能。在此基上,利用环Ş器g设计了能量@环利用系l?/span>Q通过所制备?/span>G-Azo-M作ؓ热源Qؓ相变材料供热Q实C能量的@环利用与定向输出?/span>
图文D
?/span>1.G-Azo-M自组装膜光控配位键的断开和Ş成结构示意图?/span>
Q?/span>aQ固?/span>G-Azo-Mg自组装膜光控配位键的断开和Ş成结构示意图。(bQ?/span>G-Azo-Mg的能U示意图?/span>
?/span>2.在溶液中配位键的解离和Ş?/span>?/span>
G-Azo-Mgl装体在DMF溶液中可逆Ş成和解离C意图(aQ阶D?/span>1、(bQ阶D?/span>2和(cQ阶D?/span>3。(d-fQ外光和可见光交替照射下,G-Azo-Mg?/span>DMF溶液阶段1?/span>2?/span>3中随旉变化的?/span>-可见吸收光谱。(g-iQ阶D?/span>1?/span>2?/span>3中,330?/span>660 nm处的吸收强度随时间变化曲Uѝ?/span>
?/span>3.在固态下G-Azo-Mg膜的可逆光异构化与光热能和键焓的存储和释放?/span>
Q?/span>aQ?/span>G-Azo-Mg?/span>TEM图。(bQ?/span>G-Azo-Mg?/span>XRD图谱。(cQ在紫外光充?/span>3时和蓝光放?/span>4时?/span>G-Azo?/span>G-Azo-Mg-xQ?/span>x=1Q?/span>2Q?/span>3Q薄膜的Mg 2p XPS光谱?/span>G-Azo?/span>G-Azo-Mg-xQ?/span>x=1Q?/span>2Q?/span>3Q薄膜在室温Q?/span>25.0 ?CQ下Q?/span>dQ充热和Q?/span>eQ放热过E中的异构化E度。(fQ?/span>G-Azo?/span>G-Azo-Mg-xQ?/span>x=1Q?/span>2Q?/span>3Q薄膜的一U动力学常数Ҏ。(gQ?/span>G-Azo?/span>G-Azo-Mg-xQ?/span>x=1Q?/span>2Q?/span>3Q薄?/span>DSC攄曲线。(hQ能量密度以及(iQ键焓和光热能的占比?/span>
?/span>4.G-Azo-M膜在不同条g下的储热和放热能力?/span>
Q?/span>aQ?/span>G-Azo?/span>G-Azo-MQ?/span>M = Mg2 ?/span>Fe3 ?/span>Ni2 Q的DSC曲线。(bQ能量密度和金属元素含量的关pR(cQ?/span>G-Azo-Mg在不同条件下攄的光热能比例变化?/span>G-Azo-MgQ?/span>dQ在黑暗中和Q?/span>eQ在蓝光下放热的DSC曲线。(fQ?/span>Azo?/span>G-Azo?/span>G-Azo-Mg?/span>G-Azo-Fe的能量密度与功率密度的关pR(gQ近q来Q偶氮苯基太阌热燃料的能量密度Ҏ。(hQ功率密度对?/span>?/span>
?/span>5.室温?/span>G-Azo-Mg膜在蓝光刺激下的攄q程?/span>
Q?/span>aQ在室温下,G-Azo-Mg?/span>G-Azo?/span>rGO膜在蓝光刺激下放热温度与旉变化曲线。(bQ?/span>G-Azo-Mg膜放热过E的U外热像图?/span>
?/span>6.在室温和低温下基于环形器件设计的能量循环利用pȝ?/span>
Q?/span>aQ在室温下,G-Azo-Mg膜在蓝光刺激下放热温度与旉变化曲线。(bQ?/span>G-Azo-Mg膜放热过E的U外热像图。(cQ在低温下(2-3?/span>Q,G-Azo-Mg膜在蓝光刺激下放热温度与旉变化曲线。(dQ低温下G-Azo-Mg膜放热过E的U外热像图?/span>
研究l果表明当加入不同金属离子进行配位时Q其光热性能不同Q但都优于未配位体系的光热性能。其光热性能与体pM配位金属的元素含量有养I金属元素含量高Q光储热能量密度大?/span>其中Q镁金属配位体系G-Azo-Mgh较高的能量密?/span>200.0 Wh kg-1和功率密?/span>2871.1Wh kg-1。配位体pȝ存在有利于材料自L膜,得到柔性偶氮苯-矛_?/span>-镁配位杂化材料膜Q其厚度Uؓ5微米。进一步测试其在低温下Q?/span>2.0-3.0 ?CQ的蓝光Ȁ发热释放性能Q其攄温度高达40.0 ?/span>。所释放的热能传递给相变材料Q相变材料融化Q定向流动,实现了能量的可控输出与@环利用?/span>
该研I提出的配位键调控偶氮苯化合?/span>-矛_烯杂化材料ؓ实现低温下高能量密度太阳能热燃料的光热存储及转换提供了可能性。相关研I成果近期以“Utilisation of photo-thermal energy and bond enthalpy based on optically triggered formation and dissociation of coordination bonds?/span>为题发表在期?/span>Nano Energy Q?/span>DOI: 10.1016/j.nanoen.2021.106401Q上Q文章第一作者ؓ博士生王慧,通讯作者ؓ冯奕钰教?/span>?/span>伟教授。该研I受到国家自然科学基金重炚w目的支持?/span>
天|大学伟团队长期致力于光热能材料的研IӞq年来该团队在国家自然科学基金杰出青q基金项目、重炚w目以及科技部重点研发等目的支持下在偶氮苯-x板化材料Q?/span>Nanoscale, 2012, 4, 6118Q?/span>J. Mater. Chem. A, 2015, 3, 16453Q?/span>Nanoscale, 2015, 7, 16214Q?/span>Journal of Materials Chemistry A. 2015, 3, 11787Q?/span>J. Mater. Chem. A, 2016, 4, 8020-8028Q?/span>ACS Appl. Mater. Inter., 2017, 9, 4066Q?/span>Chemsuschem, 2017, 10, 1395Q?/span>Chemical Society Reviews. 2018, 47, 7339Q?/span>Energy Storage Materials, 2019. 24: 662Q?/span>J. Mater. Chem. A, 2019, 7, 97Q?/span>Energy Storage Materials, 2020, 24, 662Q、偶氮苯有机分子和聚合物Q?/span>J. Mater. Chem. A, 2020, 8, 18668Q?/span>Macromolecules, 2019, 52, 4222Q?/span>Composites Science and Technology, 2019, 169: 158Q?/span>Chinese Journal of Polymer Science. 2019 , 37(12): 1183Q?/span>?/span>偶?/span>-相变材料Q?/span>Adv. Funct. Mater., 2020, 2008496Q?/span>Composites Communications, 2020, 21, 100402Q?/span>Composites Communications, 2021, 23, 100575Q等材料的研I和设计上取得了一pd的原创性成果?/span>
相关链接
https://www.sciencedirect.com/science/article/pii/S221128552100656X