Cov kws tshawb fawb tau ntev paub tias platinum yog nyob deb ntawm qhov zoo tshaj plaws catalyst rau splitting dej molecules los tsim hydrogen gas. Ib txoj kev tshawb fawb tshiab los ntawm Brown University cov kws tshawb fawb qhia tias yog vim li cas platinum ua haujlwm tau zoo - thiab nws tsis yog vim li cas tau xav.

Cov kev tshawb fawb, luam tawm hauv ACS Catalysis, pab daws cov lus nug tshawb fawb ze li ntawm ib puas xyoo, cov kws sau ntawv hais. Thiab nws tuaj yeem pab tsim cov catalysts tshiab los tsim cov hydrogen uas pheej yig dua thiab muaj ntau dua platinum. Qhov ntawd tuaj yeem pab txo qis emissions los ntawm fossil fuels.

Andrew Peterson, tus kws tshaj lij hauv Brown's School of Engineering thiab tus kws sau ntawv qib siab hais tias "Yog tias peb tuaj yeem txiav txim siab yuav ua li cas hydrogen pheej yig thiab ua tau zoo, nws qhib qhov rooj rau ntau qhov kev daws teeb meem rau fossil-free fuels thiab chemicals," said Andrew Peterson . "Hydrogen tuaj yeem siv rau hauv cov roj hlwb, ua ke nrog ntau tshaj CO2 los ua roj lossis ua ke nrog nitrogen los ua ammonia chiv. Muaj ntau yam uas peb tuaj yeem ua nrog hydrogen, tab sis ua kom cov dej sib faib ib qhov chaw hydrogen scalable, peb xav tau cov catalyst pheej yig dua. "

Tsim cov catalysts tshiab pib nrog kev nkag siab txog dab tsi ua rau platinum tshwj xeeb rau cov tshuaj tiv thaiv no, Peterson hais tias, thiab qhov no yog qhov kev tshawb fawb tshiab no txhawm rau txheeb xyuas.

Platinum txoj kev vam meej tau ntev tau raug ntaus nqi rau nws "Goldilocks" khi zog. Qhov zoo tshaj plaws catalysts tuav rau reacting molecules tsis dhau xoob los yog nruj heev, tab sis qee qhov hauv nruab nrab. khi cov molecules dhau xoob thiab nws nyuaj rau qhov pib tshwm sim. Tuav lawv nruj heev thiab cov molecules lo rau lub catalyst nto, ua rau cov tshuaj tiv thaiv tsis yooj yim. Lub zog khi ntawm hydrogen ntawm platinum tsuas yog tshwm sim kom sib npaug ntawm ob feem ntawm cov dej sib cais - thiab yog li cov kws tshawb fawb feem ntau tau ntseeg tias nws yog tus cwj pwm uas ua rau platinum zoo.

Tab sis muaj laj thawj los nug seb daim duab ntawd puas yog, Peterson hais. Piv txwv li, cov khoom hu ua molybdenum disulfide (MoS2) muaj lub zog sib txuas zoo ib yam li platinum, tseem yog qhov ua rau muaj qhov tsis zoo rau cov dej sib cais. Qhov ntawd qhia tias kev sib khi lub zog tsis tuaj yeem yog zaj dab neeg tag nrho, Peterson hais.

Txhawm rau kom paub tias muaj dab tsi tshwm sim, nws thiab nws cov npoj yaig tau kawm txog cov dej sib cais ntawm cov platinum catalysts siv ib txoj hauv kev tshwj xeeb uas lawv tau tsim los simulate tus cwj pwm ntawm tus kheej atoms thiab electrons hauv electrochemical tshua.

Kev tsom xam pom tau tias hydrogen atoms uas khi rau saum npoo ntawm platinum ntawm "Goldilocks" khi lub zog tsis koom nrog cov tshuaj tiv thaiv txhua lub sijhawm thaum cov tshuaj tiv thaiv siab. Es tsis txhob, lawv nestle lawv tus kheej nyob rau hauv lub nto crystalline txheej ntawm lub platinum, qhov uas lawv nyob twj ywm inert bystanders. Cov hydrogen atoms uas koom nrog cov tshuaj tiv thaiv yog qhov tsis muaj zog ntau dua li qhov xav tau "Goldilocks" lub zog. Thiab tsis yog nyob rau hauv lub lattice, lawv zaum saum lub platinum atoms, qhov twg lawv muaj kev ywj pheej sib ntsib los ua H2 roj.

Nws yog qhov kev ywj pheej ntawm kev txav mus rau hydrogen atoms ntawm qhov chaw uas ua rau platinum reactive, cov kws tshawb fawb xaus.

"Qhov no qhia peb yog tias nrhiav qhov 'Goldilocks' khi lub zog tsis yog lub hauv paus ntsiab lus tsim nyog rau thaj chaw ua haujlwm siab," Peterson hais. "Peb xav tias tsim cov catalysts uas tso hydrogen nyob rau hauv lub zog mobile thiab reactive lub xeev no yog txoj kev mus."