1
Release o Hyd ogen om Nanocon ined Hyd ides by Applica ion o Mic owa es
Luis Miguel Sanz-Mo al1, Alexande Na a e e1, Guido S u m2, Guido Link3, Mi iam
Rueda1,Geo gios S e anidis2,4 and Ángel Ma ín1*
1 High P essu e P ocesses G oup, Depa men o Chemical Enginee ing and En i onmen al
Technology, Uni e si y o Valladolid, Doc o Me gelina s/n,47011 Valladolid, Spain
2 P ocess & Ene gy Depa men , Mechanical, Ma i ime & Ma e ials Enginee ing Facul y, Del
Uni e si y o Technology, Leeghwa e s aa 39, 2628 CB Del , The Ne he lands
3 Ins i u e o Pulsed Powe and Mic owa e Technology. Ka ls uhe Ins i u e o Technology (KIT).
He mann- on-Helmhol z-Pla z-1. 76344 Eggens ein-Leopoldsha en, Ge many
4P ocess Enginee ing o Sus ainable Sys ems Sec ion, KU Leu en
Celes ijnenlaan 200 – box 2424, 3001 Leu en, The Ne he lands
Phone: +34 983184077, e-mail:[email p o ec ed] (Á. Ma ín)
2
Release o Hyd ogen om Nanocon ined Hyd ides by Applica ion o Mic owa es
Luis Miguel Sanz-Mo al1, Alexande Na a e e1, Guido S u m2, Guido Link3, Geo gios
S e anidis2,4, Mi iam Rueda1, and Ángel Ma ín1*
1 High P essu e P ocesses G oup, Depa men o Chemical Enginee ing and En i onmen al
Technology, Uni e si y o Valladolid, Doc o Me gelina s/n,47011 Valladolid, Spain
2 P ocess & Ene gy Depa men , Mechanical, Ma i ime & Ma e ials Enginee ing Facul y, Del
Uni e si y o Technology, Leeghwa e s aa 39, 2628 CB Del , The Ne he lands
3 Ins i u e o Pulsed Powe and Mic owa e Technology. Ka ls uhe Ins i u e o Technology (KIT).
He mann- on-Helmhol z-Pla z-1. 76344 Eggens ein-Leopoldsha en, Ge many
4P ocess Enginee ing o Sus ainable Sys ems Sec ion, KU Leu en
Celes ijnenlaan 200 – box 2424, 3001 Leu en, The Ne he lands
Phone: +34 983184077, e-mail: [email p o ec ed] (Á. Ma ín)
Abs ac
The elease o hyd ogen om solid hyd ides by he molysis can be imp o ed by nanocon inemen
o he hyd ide in a sui able mic o/mesopo ous suppo , bu he slow hea ans e by conduc ion
h ough he suppo can be a limi a ion. In his wo k, a C/SiO2 mesopo ous ma e ial has been
syn hesized and employed as ma ix o nanocon inemen o hyd ides. The ma ix showed high
su ace a ea and po e olume (386 m²/g and 1.41 cm³/g), which enabled he con inemen o high
concen a ions o hyd ide. Fu he mo e, by modi ica ion o he p opo ion be ween C and SiO2, he
dielec ic p ope ies o he complex could be modi ied, making i suscep ible o mic owa e hea ing.
As wi h his hea ing me hod he en i e sample is hea ed simul aneously, he hea ans e esis ances
associa ed o conduc ion we e elimina ed. To demons a e his possibili y, e hane 1,2-
diaminobo ane (EDAB) was embedded on he C/SiO2 ma ix a concen a ions anging om 11 o
31%w using a we imp egna ion me hod, and a de ice app op ia e o hyd ogen elease om his
ma e ial by applica ion o mic owa es was designed wi h he aid o a nume ical simula ion.
3
Hyd ogen libe a ion es s by con en ional hea ing and mic owa es we e compa ed, showing ha by
mic owa e hea ing hyd ogen elease can be ini ia ed and s opped in sho e imes.
Keywo ds: hyd ogen s o age, hyd ide, mic owa e hea ing, ae ogel, supe c i ical CO2.
1. In oduc ion
The inc easing sha e o sola and wind ene gy in he ene ge ic mix and he COP21 ag eemen pa e
he way o a new amily o echnologies based on enewable ene gy [1]. Since hese enewable
ene gy o ms a e luc ua ing by i s na u e, i is necessa y o de elop echnologies o s o age o
ene gy in pe iods o excess supply, o use i du ing he pe iods o excess demand. Di ec use o
hese ene gy o ms on onboa d applica ions is also no possible, and equi es an in e media e o m
o ene gy s o age.
S o age o his ene gy in o m o hyd ogen is one o he mos explo ed me hods. The challenge is
being add essed using s o age sys ems based on comp essed, lique ied and ma e ials-bounded
hyd ogen [2]. Compa ed o gas and liquid s o age anks, solid hyd ides can s o e high amoun s o
hyd ogen in small olumes, which usually a e libe a ed by a e e sible chemical eac ion by
he molysis. Howe e , cu en ly in es iga ed hyd ides a e limi ed by slow hyd ogen elease kine ics
o by high he modynamic s abili ies which make i necessa y o apply high empe a u es o
decompose hem [3]. The e o e, one o he echnological challenges which es ain he de elopmen
o hyd ides o H2 s o age is he hea ans e inside he s o age anks [4]. G ea e o s ha e been
made in o de o o e come his p oblem. Howe e , his issue can be ci cum en ed i hea ing ene gy
is deli e ed di ec ly o he ma e ial, and no by hea ans e h ough he s o age ank. Applica ion o
mic owa es o e s his possibili y.
The decomposi ion o se e al me al hyd ides unde mic owa e i adia ion was s udied by Nakamo i
e al. [5]. They concluded ha conduc i e loss and pa icle size we e he wo mos impo an
pa ame e s con olling H2 elease. Sil a Dupim e al. [6] showed ha by pa icle size educ ion an
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e ec i e hea ing o he pa icles was achie ed by app oxima ing he size o he pa icles o he
pene a ion dep h o he elec omagne ic ield in he me allic powde . They ob ained his size
educ ion by applying cold olling. Ano he al e na i e is modi ying he dielec ic p ope ies o he
complex by mixing i wi h a hyd ide which ac ua es as a mic owa e abso be , as o example
LiBH4 [7]. Zhang e al. p oposed he use o a honeycomb ce amic monoli h coa ed wi h 0.54 w %
Ni (co esponding o a hin laye o Ni o 0.2 mic on) o hold he hyd ides, which allowed he apid
hea ing o he complex [8].
An al e na i e o imp o e he kine ic decomposi ion o hyd ides is using a ca alys [9], bu his
me hod adds weigh o he complex and some imes equi es he use o expensi e me als. Ano he
al e na i e is he nanocon inemen o he hyd ide [10, 11]. By con ining he hyd ide inside he
po ous hos , hyd ide pa icle size is es ained o he po e size, and pa icle agglome a ion and
g ow h p ocess, which could ha e an ad e se e ec on he kine ic decomposi ion, a e a oided.
Mo eo e , some po ous hos s, like ca bon o silica mesopo ous ma e ials, chemically in e ac wi h
di e en hyd ides and des abilize i , u he imp o ing he decomposi ion kine ics [12]. By
combina ion o hese e ec s, he decomposi ion empe a u e and elease kine ics can be
signi ican ly imp o ed by nanocon inemen . On he nega i e side, he suppo ma e ials usually
employed, such as mesopo ous silica, ha e e y low he mal conduc i i ies ha slow down he
kine ics o hyd ogen elease i con en ional hea ing by conduc ion is applied, and he use o a
suppo ma e ial also adds weigh o he compound.
Howe e , he mesopo ous hos can be unc ionalized o p o ide addi ional p ope ies o he ma e ial
[13]. In pa icula , i can be unc ionalized o enhance he abso p ion o mic owa e ene gy, and hus
combine he main ad an ages o he wo app oaches: nanocon inemen and mic owa e hea ing.
Indeed, a po ous ma e ial wi h a high dielec ic los could con ine he hyd ide and change he global
dielec ic p ope ies o he complex. A ma e ial ha ul ills his equi emen is ca bon, which can be
manu ac u ed as mesopo ous ca bon o as ca bon ae ogel. Some esea che s ha e al eady con ined
hyd ides like NaAlH4, LiBH4 [14] o Mg(BH4)2 in o ca bon sca olds [15, 16]. Howe e , hese
5
ca bon s uc u es p esen a limi a ion which is i s low po e olume ha es ic s he space a ailable
o he con inemen o hyd ide inside he suppo . Due o his limi a ion, he maximum hyd ide
loadings achie ed in ca bon ma ixes a e be ween 15 and 30% w ., which limi s he hyd ogen
s o age capaci y below he equi emen s o p ac ical applica ions. An al e na i e could be a hyb id
ma e ial wi h lea es mo e po e space o he con inemen o a hyd ide and p o ides app op ia e
global dielec ic p ope ies o he complex, making i suscep ible o mic owa e hea ing. Silica
ae ogel was al eady sugges ed as a e y p omising ma e ial o hyd ides con inemen due o i s
ema kable su ace p ope ies, and in pa icula o i s high po e olumes ha allow con ining as
much as a 50%w o hyd ide [17]. Ca bon/silica hyb id ae ogels can combine a o able dielec ic
p ope ies wi h high po e olumes. Ca bon/silica po ous ma e ials can easily made by he
ca boniza ion o eso cinol– o maldehyde/silica ae ogels, as desc ibed by Kong e al. [18], keeping
a o able ex u al p ope ies o encapsula ion.
In his wo k, a combined C/SiO2 po ous ma e ial suscep ible o be hea ed up by mic owa es has
been syn hesized and imp egna ed wi h a hyd ide. E hane 1,2-diaminobo ane (EDAB) has been
chosen as hyd ide because o i s p omising p ope ies o H2 s o age: high H2 con en (~10 w .%)
and he absence o undesi able ola ile impu i ies in he eleased gas [19]. Ma e ial cha ac e iza ion
and H2 libe a ion es s by con en ional hea ing and by applica ion o mic owa es ha e been
pe o med in o de o e alua e he possible ad an ages o applica ion o mic owa e hea ing in
nanocon ined ma e ials. In addi ion a nume ical simula ion o he de ice unde mic owa es has
been pe o med o each be e unde s anding o he p ocess.
2. Ma e ials and me hods
2.1 Ma e ials
Reso cinol (R, ≥99% pu i y om Digma-Ald ich), o maldehyde(F, 36.5-38 % in H2O om Digma-
Ald ich), 3-(aminop opyl) ie hoxysilane (APTES, 99% pu i y om Digma-Ald ich ),
e hanol(E OH, 99.5% om Pan eac) and echnical ca bon dioxide ( om Ca bu os Me álicos) we e

6
used o he ae ogels syn hesis. Technical ni ogen ( om Ca bu os Me álicos) was used o he
ae ogels py olysis. Chlo o ime hylsilane (CTMS, ≥98% om Sigma-Ald ich) and me hanol
(MeOH, 99.8% om Pan eac) was used o unc ionalize he C/SiO2 pa icles. EDAB (96%, om
Sigma-Ald ich) and MeOH we e used o he we imp egna ion o samples.
2.2 Complex syn hesis
The eso cinol- o maldehyde ae ogels we e syn hesized ollowing he me hodology o Kong e al.
[18]. Cylind ical monoli hs we e made by using R:F:APTES:E OH, in a mola a io o 1:2:1:60.
A e gela ion he alcogels we e d ied by using supe c i ical CO2 in o de o a oid capilla y s esses
du ing sol en emo al which could damage de ae ogel s uc u e. The d ying ook place in a closed
ci cui . The alcogels we e placed in a chambe which can be isola ed om he es o he ci cui .
Then CO2 was pumped ill 10.5 MPa and hea ed ill 40°C. A e i he CO2 was eci cula ed ill he
sol en was comple ely emo ed. Th ee loads o esh CO2 whe e needed o a comple e d ying o
he gels. A de ailed desc ip ion o he se up can be ound in a p e ious wo k [20].
Subsequen ly he RF/SiO2 ae ogels we e py olysed in a homemade ubula o en. The samples we e
hea ed ill 800°C we e he T was held o 3 hou s. All his p ocess was made unde ine a mosphe e
(~10 NmLN2/h). The py olysed monoli hs we e hen milled in a plane a y ball mill (PM100 om
Re sch) a 100 pm du ing 3 h. The esul an powde was imme sed in a CTMS MeOH mix u e
o e nigh , in o de o minimize he hyd oxyl and ca boxyl con en o he ma ix su ace which
could des abilize he imp egna ed hyd ide. The es o he unc ionaliza ion agen was washed wi h
excess o MeOH.
Finally he powde s we e loaded wi h EDAB by we imp egna ion, using MeOH as sol en o he
hyd ide (28 mg/mL).
2.3 Ma e ial Cha ac e iza ion
7
The chemical s uc u e o he complex was s udied by Fou ie T ans o m In a ed Spec oscopy (FT
IR model TENSOR om BRUKER).
The c ys allini y o he imp egna ed EDAB was analyzed by X- ay di ac ion (Disco e D8-
B uke )
Di e en ial scan calo ime y (DSC) assays we e pe o med wi h a Me le -Toledo 822e de ice. The
hea ing a e was 5°C/min om 30 o 250°C unde a N2 cons an low o 60 mL/min.
The ex u al p ope ies o he complex we e de e mined by ni ogen iso he mal adso p ion-
deso p ion. A Su ace A ea and Po osi y Analyze (ASAP2020 om Mic ime ics) was used. The
speci ic su ace a ea was calcula ed by he BET (B unaue –Emme –Telle ) me hod. The speci ic
po e olume was de e mined by he single poin adso p ion me hod. The a e age po e diame e was
calcula ed wi h he deso p ion iso he m o he Ba e -Joynes-Halenda (BJH) me hod.
The de e mina ion o he complex dielec ic p ope ies was ca ied ou by means o a ca i y
pe u ba ion me hod desc ibed by Ramopoulos e al. [21]. Namely, he powde ed sample was
in oduced in a qua z ube (inne diame e 7.8mm) wi hou compac ion. 0.49cm3 o ma e ial was
es ed o samples wi h ~11%w EDAB. Then, he sample was in oduced a he cen e o a TE-111
mode ca i y wi h a esonance equency close o 2.45GHz.
2.4 Nume ical simula ions. Design o hyd ogen libe a ion cell
The design o he cell used in hyd ogen libe a ion expe imen s by applica ion o mic owa es was
suppo ed on a nume ical simula ion. Fo his, he p ocess o mic owa e hea ing and elease o he
hyd ogen om he ma e ial is ep esen ed in his wo k by h ee basic s ages [22, 23]:
1) Gene a ion o he mic owa es in he magne on.
2) P opaga ion o he elec omagne ic wa es.
3) Hea gene a ion and ans e in he ma e ial.
8
The model combines all ele an physics. I simula es he elec omagne ic in e ac ions in he
mic owa e ci cui , including he o wa d and backwa d in e ac ion be ween he applica o sec ion
o he ci cui and he magne on mic owa e sou ce. This was done ia mic owa e ne wo k analysis.
The ime ha monic s a iona y mic owa e ield was simula ed o e he applica o sec ion o he
mic owa e ci cui including he load, while he cha ac e is ics o he mic owa e sou ce we e
ep esen ed by an idealized lumped magne on model. The model cha ac e is ics we e desc ibed in
mo e de ail in a p e ious wo k [22]. Mo eo e , he model also included conduc i e hea ans e .
Using he in e ac ion be ween elec omagne ic wa es and he ma e ial in o ma ion, he empe a u e
and hea gene a ion we e p edic ed. The medium pa ame e s ele an in he elec omagne ics model
a e he ela i e pe mi i i y o he ma e ials p esen in he mic owa e ci cui . The dielec ic
p ope ies o he composi e, measu ed as desc ibed ea lie , we e in oduced in he model. All he
simula ions we e ca ied ou using Comsol Mul iphysics® 3.5 [24].
2.5 Hyd ogen libe a ion expe imen s.
To decompose he hyd ide and libe a e hyd ogen, he sample was hea ed by wo di e en me hods:
- By con en ional hea ans e , in oducing he essel in a gas ch oma og aphy o en (Agilen
7890).
- Wi h a mic owa e o en (CEM Disco e ), by placing he essel e ically, cen e ed and a a
high o 3cm om he bo om o he ca i y.
Tempe a u e was ollowed by placing a ibe -op ic empe a u e senso TS2 (OPTOCOM) inside he
in e nal capilla y o he glass essel. The H2 low gene a ed by he he molysis was measu ed by a
olume ic me hod by using a ully open mass low con olle s (EL-Flow F-200 om B onkho s )
wi h anges om 0.02 o 1 mL min-1. In hese measu emen s, i was conside ed ha all he eleased
gas was hyd ogen. This supposi ion ag ees wi h a ailable expe imen al da a, which indica es ha
he gas p oduced a he ope a ing empe a u es conside ed in his wo k is nea ly pu e hyd ogen [25].
While he p esence o decomposi ion by-p oduc s in he gas canno be disca ded, he p esence o
9
such compounds a mino concen a ions would ha e a negligible in luence on hyd ogen low a e
calcula ions, which a e he main ocus o his wo k. On he o he hand, he p esence o hese
compounds would ha e a s ong impac on he ope a ion as hey can damage uel cells e en a low
concen a ions, and he e o e hei p esence should be e alua ed in u u e wo ks.
3. Resul s
3.1 Ni ogen iso he mal adso p ion-deso p ion iso he ms
Table 1 shows he main ex u al p ope ies o he non-imp egna ed ae ogel and he imp egna ed
ones. Ca bon ae ogels ob ained om he py olysis o eso cinol o maldehyde a e mic opo ous
ma e ials wi h po e olume unde 1 cm3/g [26]. By con as , silica ae ogels a e mesopo ous
ma e ials wi h high po e olume (abo e 2 cm3/g) [27]. By mixing silica and ca bon i is in ended o
main ain he high he po e olume o silica ae ogels, which is impo an in o de o ha e enough
po e space o con ine he hyd ide. Resul s p esen ed in Table 1 demons a e ha he ma e ials
ob ained combining silica and ca bon ha e po e olumes abo e 1 cm3/g. In he po e diame e
dis ibu ion, p esen ed in Figu e 1, wo sepa a e egions o mic opo es and mesopo es a ibu ed o
he ca bon and silica egions a e dis inguished, wi h a b oad mesopo ous size dis ibu ion.
As could be expec ed, by imp egna ing hyd ide a signi ican dec ease o he su ace a ea and he
po e olume is obse ed, illing and blocking he smalle po es a his concen a ion o hyd ide
(~11%). Conce ning he iso he ms showed on Figu e 1, he sca olds p esen ype IV iso he ms,
ypical o mesopo ous ma e ials. In addi ion, adso p ion and deso p ion b anches a e almos e ical
and nea ly pa allel o e an app eciable ange o gas up ake, co esponding o a beha io classi ied
as hys e esis loop H1. This kind o po ous ma e ial consis s o well- aligned, sphe es and b ique es
[28].
Table 1.Tex u al p ope ies o he samples.
BET Su ace
A ea (m2/g)
-Plo
Mic opo e
A ea
(m2/g)
-Plo
Ex e nal
Su ace
A ea
Po e
Volume
(cm3/g)
Po e
diame e (Ø)
(nm)
16
and he empe a u e s a ed o d op as soon as he mic owa e was s opped. A he end o he es he
powe was hold ill he o al amoun o hyd ogen con ained in he sample was exhaus ed. The
esul s o his es a e shown in Figu e 7.
Figu e 7. H2 low and sample empe a u e du ing a libe a ion es wi h mic owa e pulses o 25W
Finally, i mus me no ed ha he e e sibili y o he hyd ogen s o age-libe a ion p ocess is dependen on he
hyd ide compound employed o s o e hyd ogen. As a he momen he e is no any p ocedu e a ailable o
make he decomposi ion o EDAB e e sible, he p oposed compound is no e e sible. Howe e , he same
me hodology p oposed in his wo k could be used wi h o he hyd ides ha a e e e sible, such as me allic
hyd ides.
3.6 IR Spec oscopy
Figu e 8 shows he IR spec a o he complex be o e and a e H2 elease es s. The py olysed
ae ogel shows in ense silicon–oxygen co alen bond ib a ions, appea ing mainly in he 1200–1000
cm−1. The e y in ense and b oad band appea ing a 1050 cm−1 and he shoulde a a ound 1200

17
cm−1 a e espec i ely assigned o he ans e sal op ical and longi udinal op ical modes o he Si-O-
Si asymme ic s e ching ib a ions. On he o he hand, he symme ic s e ching ib a ions o Si-O-
Si appea a 800 cm−1 [31]. The s ong band a 1569 cm-1 s ems om he a oma ic C=C s e ching
ib a ions o he ca bons [32]. The b oad band cen e ed a a ound 3100–3600 cm−1 co esponds o
he o e lapping o he O-H s e ching bands o su ace silanols and ca boxylic g oups.
Fu he mo e, he Si-O in-plane s e ching ib a ions o he silanol Si-OH g oups appea a a ound
960 cm−1. The su ace unc ionaliza ion wi h CTMS has educed he in ensi y o he wo OH a eas.
In addi ion he band a 1705 cm-1 o he un ea ed ca bons ela ed o he ca bonyl and he one a
1359cm-1 (OCO) [33] ha e disappea ed because o he ea men wi h CTMS. Ins ead, CH peak
appea s a 740 cm−1, 1249 cm−1 and 2965 cm-1 (CH3) and he Si-C s e ching ib a ion a 841 cm−1.
These wo peaks con i ms he eplacemen o some hyd oxyl g oups by alkyl g oups. This
unc ionaliza ion causes a dec ease o he oxygen g oups on he suppo su ace, a oiding he
chemical in e ac ions be ween EDAB and he suppo which could des abilize EDAB.
The spec a o he imp egna ed ae ogel shows he ypical peaks o EDAB: 702 cm−1 o he BN
bond; 1039 cm−1 o CN bond; 1162 cm−1 and 1189 cm−1 o BH bond and 1357 cm−1, 1581
cm−1,3221 cm−1 and 3257 o NH bond. A e decomposi ion, BH and NH peaks disappea , and wo
new bands a 1326 cm−1 and 1362 cm−1 g ow s onge . These bands a e cha ac e is ic o B=N
s e ching, hus e idencing he o ma ion o double bonds be ween B and N [25]. The only sample
which keeps he BH and NH signals a e he hea ing is he one pe o med a 10W in he
mic owa e. As i was desc ibed abo e, his powe was no high enough o each he decomposi ion
empe a u e, which jus i ies he p esence o hyd ogen bonds in he sample a e hea ing.
Fu he mo e, his esul p o es he s abili y o he composi e a empe a u es below i s
decomposi ion empe a u e.
18
Figu e 8. In a ed spec a o EDAB and he imp egna ed complex be o e and a e he H2 eleased.
4. Conclusions
A hyb id C/SiO2 ae ogel has been syn hesized and unc ionalized keeping high po e olume in
o de o hold EDAB inside i s po es. The con inemen o he hyd ide has allowed educing he
esponse ime du ing he decomposi ion and has minimized he second decomposi ion s ep
cha ac e is ic o pu e EDAB.
19
The addi ion o ca bon o he ma ix has modi ied he dielec ic p ope ies o he ma ix and has
allowed hea ing up he sys em by using mic owa es, imp o ing he hea ing a e. In addi ion his
hea ing a e could be easily con olled by uning he powe o he elec omagne ic ield. Wha is
mo e, he sys em jus hea s up he sample, and no he con aine . The e o e he he mal ine ia is
educed in compa ison wi h adi ional hea ing, and he empe a u e s a ed o d op as soon as he
mic owa e was s opped, allowing con olling he p oduced hyd ogen low in esponse o
luc ua ing demands.
Aknowledgemen s
This esea ch has been inanced by he Spanish Minis y o Economy and Compe i i eness h ough
p ojec ENE2014-53459-R. L.M. Sanz-Mo al hanks he Spanish Minis y o Economy and
Compe i i eness o a FPI p edoc o al g an .
20
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[2] M. Ismail. E ec o LaCl3 addi ion on he hyd ogen s o age p ope ies o MgH2. Ene gy 79
(2015) 177-182.
[3] U. Ebe le, G. A nold, R. on Helmol . Hyd ogen s o age in me al-hyd ogen sys ems and hei
de i a i es. J. Powe Sou ces 154 (2006) 456-460.
[4] B. D. MacDonald, A. M. Rowe. Expe imen al and nume ical analysis o dynamic me al hyd ide
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Figu e Cap ions
Figu e 1. Ni ogen adso p ion iso he ms and po e size dis ibu ion o he aw ae ogel and he
imp egna ed one.
Figu e 2. X- ay di ac ion pa e ns o he aw ae ogel and he imp egna ed one.
Figu e 3. DSC p o ile o EDAB and he imp egna ed complex be o e and a e H2 elease.
Figu e 4. Simula ion esul s. On he le , hea sou ce (W/m3); on he cen e, T (K); on he igh ,
dimensions o he glass essel
Figu e 5. E olu ion o empe a u e du ing hyd ogen libe a ion es s by con en ional hea ing and by
applica ion o mic owa es
Figu e 6. H2 low du ing he libe a ion es s
Figu e 7. H2 low and sample empe a u e du ing a libe a ion es wi h mic owa e pulses o 25W
Figu e 8. In a ed spec a o EDAB and he imp egna ed complex be o e and a e he H2 eleased.