海水也能產H2O?單原子光催化最新研究!

2023-08-09 22:23:04 字數 3924 閱讀 4640

海水是地球上最豐富的水資源,然而,迄今為止,海水中的鹹鹽含量一直阻礙了將其直接用於催化反應的應用。隨著環境問題的日益突出,對可持續發展和綠色化學技術的需求不斷增長,科學家們正在積極探索開發能夠從海水中產生高效催化反應的新材料和技術。最近,一項名為的研究引起了廣泛關注。該研究團隊開發了一種新型催化劑,可以直接從海水中產生過氧化氫(h2o2),並展示了優異的反應活性和**利用效能。

傳統上,過氧化氫通常通過兩電子氧還原反應(orr)生成,其中間體過氧化物在單原子位點附近形成。然而,該研究中使用的催化劑採用了不同的雙電子水氧化反應(wor)途徑,在海水中產生h2o2。具體來說,通過光催化反應,催化劑上的光致空穴(h )可以直接將h2o氧化為h2o2,或者通過首先氧化氫氧根(oh-)離子生成羥基自由基(?oh),然後將兩個?oh間接結合形成h2o2。這種新型wor反應路徑打破了傳統觀念,並為相關催化反應的研究提供了新的思路。

為了實現海水中h2o2的光催化產生,研究團隊開發了一種新型芳基氨取代的石墨氮化碳(g-c3n4)催化劑,其中包含具有原子級分散的錳(mn)。通過將錳successfullyimplementingthedirectgenerationofhydrogenperoxide(h2o2)fromseawaterisachallengingprocessduetoitshighsaltcontent.however,arecentstudytitled,"efficientlight-drivenh2o2productionfromseawaterenabledbyatomicallydispersedmnongraphiticc3n4"hasdevelopedacatalystthatcanachievethisfeat.thenovelcatalyst,whichconsistsofatomicallydispersedmanganese(mn)onaromaticamine-functionalizedgraphiticcarbonnitride(g-c3n4),exhibit***cellentreactivityandstability.underthesameconditions,thecatalystcanproduceupto2,230μmofh2o2inalkalinewaterwithin7hoursandupto1,800μmfromseawater.notably,thecatalystcanbeeasilyrecoveredandreusedwithoutsignificantlossofperformance.

thecatalystoperatesthroughanuncommondoubleelectronwateroxidationreaction(wor)pathwaytoproduceh2o2insteadofthetypicaltwo-electronoxygenreductionreaction(orr)pathway.thedirectandindirectworprocessesoccur,wherephotogeneratedholes(h )directlyoxidizeh2ointoh2o2throughaone-steptwo-electronworprocess,orh initiallyoxidizeshydroxide(oh-)ionsintohydroxylradicals(?oh),whichthencombinetoformh2o2.

theresearchersdevelopedthiscatalysttoaddressthegrowingdemandforh2o2,whichiswidelyusedasagreenoxidantinvariousindustriessuchasorganicsynthesis,pulpand***bleaching,wastewatertreatment,anddisinfectants.additionally,h2o2canbedirectlyusedinsingle-compartmentfuelcellsasithasacomparableenergydensitytoh2andiseasiertostoreandtransport.however,theconventionalindustrialproductionofh2o2isenergy-intensiveandgeneratesharmfulbyproducts.thus,exploringalternativemethodssuchasphotocatalyticoxidationofwatertosynthesizeh2o2ishighlypromising.

whilevarioushomogeneousphotocatalysts,clusters,nanoparticles,andsingle-atomcatalysts(sac)h**ebeenreportedforh2o2production,moststudiesh**efocusedonnoblemetalssuchasplatinum(pt)andpalladium(pd).theutilizationofthe3dtransitionmetals,particularlymanganese(mn),assacsisrelativelylimitedduetotheirlowerreactivitycomparedtoothermetals.therefore,thisstudy'sdevelopmentofamanganese-basedcatalystrepresentsanimportantadvancementinthefield.

overall,thestudypresentsanovelapproachforsynthesizingametal-g-c3n4catalystwithhighatomicdispersionandcoordination-unsaturatedmetal-nxsitesfromnon-precioustransitionmetals.thiscatalystdemonstrate***ceptionalreactivityandstabilityforlight-drivenh2o2productionfromseawaterwithouttheneedfororganicelectrondonors.thefindingsshedlightonthesynergisticinteractionbetweenthemetalandgraphiticcarbonnitride,whichcouldpotentiallyinspirethedesignofotherefficientcatalystsforvariousphotocatalyticreactions.thisresearchholdsgreatpromiseforthepracticalapplicationofh2o2productionfromseawater,offeringasustainableandgreenalternativetoconventionalmethods.

從“青銅”到“王者” 零基礎學員也能掌握的2個雅思口語技巧

雅思口語有一套科學而成熟的評價體系,能夠綜合概括乙個人的英語口語能力。想要實現從 青銅 到 王者 的突破,同學們可先要自測一下你是否了解這套 遊戲規則 又在什麼地方有欠缺哦 這就像 你是個好人,但我們不合適 大多數人聽了都想要追問 那到底是 不合適呢?快展開說說啊。這篇推文可能會給你想要的答案。每個...