相关课程纳米学院cch lecture

《材料物理化学》讲座第一讲：新能源技术与材料New

Energy

technology

and

materials陈

( :

cc

)Department

of

Materials

Science

and

EngineeringUniversity

of

Science

and

Technology

of

China引言Why

new

energy

technology?我国能源持续供应能力石油资源原油储量分布中东

66.4％南美7.8％7.5％非洲6.6％东欧

5.8％西欧1.8％亚洲3.9％中国储量可采储量澳大利亚0.2％940亿吨52.6亿吨（占世界第12位）占世界储量的2.43%生产与需求2001年石油产量1.65亿吨2003年石油产量进口量2005年石油产量进口量进口量 0.7亿吨（原油）0.3亿吨（成品油）1.69亿吨（原油）0.1442亿吨（成品油）0.8299亿吨（原油）1.82亿吨（原油）1.3亿吨（原油）(

消费量为4366万吨)2007年进口量2008年进口量1.63亿吨（原油）0.338亿吨（成品油）1.79亿吨（原油）现在，我国石油对外依存度为50%.2011年：55%；2020：预计65-70%52.6

(1.79

2)

14.7(年)煤炭资源世界上最大可能储量10.6万亿吨世界探明可采储量9842亿吨大约可供开采150―200年中国保有储量10070.7亿吨（国家

1998）1650亿吨（世界第三位）,为世界人均储量的45%中国可采储量2001年中国原煤产量

11.1亿吨标准煤2003年中国原煤产量

19亿吨标准煤2005年中国原煤产量

21.9亿吨标准煤Syngas

(H2

+

CO)C

+

H2O

→

CO

+

H2C

+

O2

→CO2CO2

+

C

→2COCH4

+

H2O

→

CO

+

3H2CO

+

H2O

→

CO2

+

H2(water

gas

shift

reaction

)As

a

fuel,

most

often

produced

bygasification

of

coal,

biomass

ormunicipal

waste.As

an

intermediate

in

industrialsynthesis

of

hydrogen

(e.g.

NH3production),

produced

fromnatural

gas

(

reformingreaction)EnergysourcesGas

separationMembranesCatalysisCO2-removalH2-technologyFuel

cellsSustainableEfficientEnvironmentaland

climatefriendlyHydropowerSun,

wind,

waveGasGas/liquidfuelImprovedefficiencyReducedemissionsCO2

and

NOxStorageHydrogenSOFC

PEMSolar

cellsPhotolysisElectrolysisNew

energy

technologyUSEElectromotors;

HeatElectricityBatteries

CapacitorsElectricity

storage

andusePart

1:

电化学基础Electrochemistry

basicsThe

amount

of

electricity

that

flows

through

the

celldepends

on

the

amount

of

species

being

oxidized

or

reducedaccording

to

the

Faraday

law:Am

it

MnFI

=

dQ/dt Q

=

∫IdtElectricity:n-

number

of

electrons

in

a

redox

reaction,

N-number

of

moles,MA-

molecular

weight,

F-

Faraday

constant

(96485C/mole)In

an

electrochemical

reaction:

aA

+

bB

==

gG

+

hHG0

=

-nFE0

G

=-nFE E=E0

–

(RT/nF)lnQrS

=

nF(E/T)P

rH

=

-nFE

+nFT(E/T)PΔGocell

=

-nFEocellEocell=

Eocathode

–

Eo

eanodIf

Eocell>

0,

thentheprocess

is

spontaneous(galvanic

cell)If

Eocell<

0,

then

theprocess

isnonspontaneous(electrolytic

cell)Part

2:

氢能与膜分离技术Natural

gas

as

energy

sourceExchange

of

coalan l

by

more

environmentalfriendly

natural

gasNatural

gas

for

use

in

fuel

cellsNatural

gas

as

source

for

hydrogen

(or

hydrogencarriers)Impact

of

membrane

technology

on

GTLOxygenPlantReformerFisher-TropschReactorSeparation

/UpgradingSyngas

ReactorFisher-TropschReactorSeparation

/UpgradingConventional

ProcessLiquid

Products15

%Air30%Ceramic

Membrane

ProcessAirNat.

Gas

/Liquid

ProductsNat.

Gas

/30

%

25

%CAPITAL

INVESTMENTEthyleneOlefinsSynthesisMTOPropyleneBy-productsNatural

GasMethanolSynthesisSynthesisGasProductionSyn.Gasto

MeOHGas

To

Olefins

(GTO)Catalysts

for

gas

conversionThe

UOP/Hydro

Methanol

To

Olefins

ProcessCatalysts

for

gas

conversionThe

gas

to

syngas

ProcessMTO

ReactionsCatalystD

oCButenesThe

unique

pore

sizeallows

selectiveconversion

to

olefinsand

excludes

heaviercompoundsMethanolCH3OHEthyleneC2H4PropyleneC3H6Catalysts

for

gas

conversionThe

Propane

DeHydrogenation

processHydrotalciteHeat(Mg,Al)O

supportPropane

C3H8Propylene

C3H6

+

H2Mg6Al2CO3(OH)16·4(H2O)+

catalystimpregnationPt,

Sn水滑石Oxides

for

energy

technologyOxygen

permeable

membranes

(ceramic

membranes)dense

materials;

oxygen

transport

by

atomic

diffusioninfinite

O2

selectivity;

operation

at

high

temperaturesMixed

conductors;

electron

and

oxygen

ion

transportchemical

stability;

thermal

and

chemical

expansionPurification

of

air

for

use

in

oxidation

processesultra

clean

syngas

production

(NOx

reduction)GTL;

lowering

of

greenhouse

gas

emissions;

CH4,

CO2Related

materials

used

in

SOFC;

of

interest

as

high

Tc,

CMR,

etcMaterials

for

oxygen

permeable

membranesH2OAir

+

CH4N2

xH2

+

COO2-2e-MembraneO2氧气分离方法氧气分离方法低温分馏:能耗高,设备体积大,

投资大,集中生产会带来

问题；变压吸附:无法实现连续生产,生产效率低,O2选择性低,得到的氧气纯度不高；氧分离膜:理论氧分离效率为100%,能耗低,过程简单,成本低,且能方便的与耗氧工艺耦合,可以降低氧气的生产成本30%。低温分馏工作原理&氧渗透理论“离子-电子混合导体”Def：氧离子迁移数t

i偏离于1，即体系同时存在氧离子电导及电子电导图1

混合导体透氧膜的氧渗透原理图图2

混合导体透氧膜氧渗透过程的等效电路图氧渗透过程从宏观上看就是氧气从高氧分压端经体相扩散渗透到了低氧分压端，工作中的混合导体透氧膜可看作是一个

短路的氧的浓差电池。工作原理&氧渗透理论R

s’和Rs”：高、低氧分压端表面交换电阻，Rbi和Rb

：氧离子和电子(空穴)体相迁移电阻，elE

和

I

： 电池的理论电动势和电流。浓差电池的理论电动势为:氧离子和电子空穴定向迁移引起的内电流与氧渗透流量FO2的关系为:→Rs＞＞Rb，表面交换控制过程；

Rs＜＜Rb，体相扩散控制过程；

Rs≈Rb，共同控制过程。工作原理&氧渗透理论(Nernst

Equation)没有外电场存在时的氧渗透率为：工作原理&氧渗透理论双极电导率σamb(ambipolar

conductivity)根据氧化学势的定义：沿膜厚L

积分得：σi，σel不受氧分压影响（Wagner

公式）σi＜＜σel（JO2∝σi）分类混合导体图3

氧离子缺陷传导机制示意图单相 双相Def：氧离子和电子在同一相中

Def：氧离子和电子有不同且相传导 互独立的

通道相结构组成氧空位间隙氧氧离子缺陷物种图4

不同相结构组成的混合导体混合导体透氧膜的种类及研究概况单相混合导体钙钛矿型结构（ABO3）特点：A位和B位具有很强的掺杂能力☆低价离子在A位掺杂能形成大量氧空位，具有良好的氧离子导电性；☆在B位掺杂的过渡金属离子又具有较强的变价能力。这类材料通过Zener双交换机制传导电子电能良流及氧空位传导氧离子，从而形好的离子—电子混合导体。Ln1-xAxCo1-yByO3-δ(Ln=

La，Gd，Sm，Nd，Pr，A=

Na，Ca，Ba，Sr，B=

n，Fe，Co，Ni，Cu)、Y0.05BaCo0.95O3-δ、La1-xMxCrO3-δ(M=Ca，Sr，Mg)、Y0.1Ba0.9CoO3-δ、CaTi1-xMxO3-δ(M=Fe，Co，Ni)、Ba0.5Sr0.5Co0.8Fe0.2O3-δ。0.8

0.2

3-δ

0.5

0.5

0.8

0.2

3-δ其中SrCo

FeO

和Ba

Sr

Co

Fe

O

在850℃以上的air/He梯度下透氧量达到10-6mol/cm2⋅s类钙钛矿型结构（AO(ABO3)n）Ruddlesden-Poppern=1，代表物质：La2NiO4晶体结构：层状，c轴方向是由LaO和LaNiO3钙钛矿交替而成对其进行掺杂可提高透氧能力。Sr

Fe

O

，SrCoFe O

，Bi

Sr

CaCuO

，YBa

Cu

O4 6

13 0.5

y

2

2

8

2 3

6+δLa

Ni Fe

O和La

Cu2 1-x

x

4+δ2 1-x

x

4+δCo

O

在850℃的透氧速率10−7mol/cm2⋅s双相混合导体结构特点：两个组成相之间化学兼容性要好，且热膨胀系数和烧结温度都必须相近。☆氧离子导电相：稳定的ZrO2，掺杂的CeO2等☆电子导电相： 金属，高电导率的氧化物La0.6Sr0.4MnO3-δ

La0.8Sr0.2Cr0.5Fe0.5O3-δ

La0.8Sr0.2Cr0.5Mn0.5O3-δLa0.8Sr0.2CrO3-δ

、La0.8Ca0.2CrO3-δ-YSZ、SDC

Au、Ag、Pd、Pt双相混合导体相对单相透氧量相差一个数量级钙钛矿型结构（ABO3）3

n类钙钛矿型结构（AO(ABO)）试验装置图airO2

depleted

air状膜b）管状膜图6

氧渗透性能测试装置基于透氧膜的膜反应器用于

气CH4Pure

O2致密陶瓷透氧膜Mainly

CO,H2Little

CH4

,CO2,H2OAirO2

depletedair主要反应:2CH4+O2=2CO+4H2稳定性考虑，选择双相混合导体材料；透氧量考虑，选择中空纤维膜。近期工作：LSCF-YSZ（SDC）中空纤维膜进行POM燃烧-重整串联膜反应器构造示意图两段式（燃烧-重整）Ni/-Al2O3催化剂

→→SrFeCo0.5O3.25XCH4FO2OCM透氧膜反应器中OCM反应机理示意图OCM试验结果材料体系C2选择性产率La0.6Sr0.4Co0.8Fe0.2O3-δ70％<5%(LSCFO)La-Ba-Co-Fe-O

(LBCFO)>50％—Ba0.5Sr0.5Co0.8Fe0.2O3-δ(

BSCFO)>50%~10%BaCe0.8Gd0.2O3-δ62.5%16%相对于固定床反应C2选择性的20%，上述实验结果均比常规反应器中反应的结果要高，表明利用MIEC透氧膜反应器进行OCM反应确能提高C2的选择性。过去300空气中的CO2浓度变化图过去140年平均气温变化图温室气体减排温室气体CO2在大气中含量的增加，已经导致了全球平均温度在过去几十年里一直呈现增加的趋势,控制大气中CO2的含量已经成为国际社会的共识。唯一的办法就是进行CO2的捕获。三种捕获方法：燃烧前除碳、纯氧燃烧、燃烧尾气中CO2捕获。现有O2/CO2燃烧技术流程示意图CO2

捕获燃烧气体净化低温分离空气O2

O2

/

CO2CO2循环现有O2

/CO2燃烧技术流程图需额外消耗30%的能量用于分离氧气和压缩CO2空气分离能耗大、投资高、增加电厂占地面积基于透氧膜的新型O2/CO2燃烧技术CO2

捕获燃烧气体净化O2

/

CO2CO2循环基于陶瓷透氧膜的新型O2/CO2燃烧技术流程图空气分离成本低、能量损失小、投资小新型O2/CO2燃烧技术特点优点可实现CO2零排放NOx排放量低，<<1ppm能量损失小(相对于O2/CO2燃烧技术)存在的难题合适的透氧膜材料膜材料加工工艺高温热交换设备O2/CO2燃烧技术透氧膜材料要求：耐CO2侵蚀，相当的透氧量。SrCo0.8Fe0.2O3-δ

（SCF）体系中B位掺杂Ti，Zn，Zr。试验结果表明材料耐CO2性能和透氧性能都很好。基于透氧膜的新型O2/CO2燃烧技术Sr(Co0.8Fe0.2)1-xTix

O3-δ

(0≤x≤0.4)在CO2气氛下的重量和透氧量变化曲线基于透氧膜的零排放电池技术前置重整器LSCF-YSZ后置燃烧器LCC-SDCUSTC:

two-stage

oxygen-permeablemembrane

reactora)

The

chemical

conversionsin

different

areas

of

themembrane

reactorb)

the

construction

anddimensions

of

the

reactor.Angew.

Chem.

Int.

Ed.

2003,

42,

5196

–5198Ceramic

membrane

reactorsO2-permeable

hollow

fibres

and

capillaries

with

an

oxygen-flux

0.5

m3/m2

h

barHigh-temperature

module

up

to

900°C

housing

oxygen-permeable

membranesof

0.1

m2

areaFull-ceramic

module

with

1

m2

microporous

and

catalytically

active

membraneareaTechnologies

for

the

catalytic

coating

of

membranes/modulesPart

3:能与能电池第一代能电池第二代能电池第三代能电池单晶硅25.9%，20.3%多晶硅20.4%，15.5%非晶硅11.7%，10.4%CdTe

16.7%，10.9%CIS

19.9%，13.5%敏化电池10.4%有机薄膜电池5.15%纳米结构电池太阳能电池Schematic

of

a

Photovoltaic

(solar)

cellSchematic

representation

of

the

principal

of

thenanocrystalline

injection

cell

(dye

sensitized

heterojunction

solarcell)Dye-sensitized

solar

cellRef.Home

page

in

renewableresearch

center

in

ColoradoPhotoelectrochemical

CellPhotoelectrochemical

CellS+hνS*S*

S++e-CB(TiO2)S++A-A+e-(CE)S+AA-Voc=1/q【（Ef）TiO2

－(E（R/R-）)】Dye-sensitized

solar

cellTiO2DyeRef.

M.Gratzel.

Acc.Chem.Res.

2000敏化剂分类联吡啶金属络合物系列酞菁（Phthalocyanine）系列卟啉（Porphyrin）系列纯有机系列NNNNHOOCCOOHCOOHCOOHRuSCNNCSN3NNNRuHOOCCOOHCOOHNCSNCSSCNBlack

dyeRef:

Nazeeruddin

M.K.,

etal.,

J.

Am.

Chem.

Soc.,

1993,115,6382Nazeeruddin

M.K.,

et

al.,Chem.

Commun.,

1997,1705-1706联吡啶金属络合物系列Wavelength

[nm]Ref:

Hagfeldt

A.

and

Grätzel

M.,

Acc.

Chem.

Res.,2000,33,269-277Black

dyeRef:

N

azeeruddinM

K,

GratzelM

J.Am.Chem.Soc.1993,

115:

6382Hagfeldt

A.

and

Grätzel

M.,

Acc.

Chem.

Res.,2000,33,269N3

和Black

Dye性能比较NNNNNNNNRRRRMNNNNMRRRR卟啉系列和酞菁系列Ref:

(1)A.Kay,

M.Gratzel,

et

al.,J.Phys.Chem.1993,97,6272(2)

M.M.

Ressler

and

R.K.

Panday,Chemtech,1998,3.39Ref:Sayama

K.,etal.,

Chem.

Commun.,

2000,

1173NSCHCHNSOSC18H37COOHMerocyanine

derivative,

Mb(18)-N

with

an

overall

η

=4.2%纯有机系列（一）半菁衍生物Ref:

Hara

K.,

et

al.,

New

J.

Chem.

2003,27,783OCNCOOHNOONOSSHOOCCNNKX-2311NKX-2677纯有机

系列（二）香豆素衍生物Dye-sensitized

solar

cellRef.

Homepage

in

Gratzelgroup电解质材料液态电解质存在的缺点：易导致敏化

的脱附;溶剂易挥发,与敏化作用导致降解;密封工艺复杂;载流子迁移速率很慢,在高强度光照时不稳定;存在其他氧化还原反应……Ref：Tennakone

K,

Perera

V

P

S

,

et

al

.

J

.

Phys.

D:Appl

.

Phys.

,1999

,32

,374.固态空穴传输材料Grätzel

等人在1998年用2,2’,7,7’-四(N,N-二对甲氧基苯基氨基)-9,9’-螺环二芴(OMeTAD,如下图所示)作为空穴传输材料,得到了单色效率高达33%的电池。Bach

U

,LupoD

,Comte

P

,

et

al

.

Nat

ure

,1998

,395

:583Photoelectrochemical

Cellmetale

-h+Light

is

Converted

to

Electrical+Chemical

EnergyLiquidSolidSrTiO3KTaO3TiO2SnO2Fe2O3Solar

semi-conductor

device.

(Ga,

In,

and

P,

elements).传统能电池分类各类能电池效率Prog.

Photovolt:

Res.

Appl.

2006;

14:45–51含镓的铜铟电池19.5±0.6国家可再生能源0.410cm2面积碲化镉电池16.5±0.5国家可再生能源1.032

cm2面积多晶硅薄膜电池16.6±0.4德国斯图加特大学4.017cm2面积纳米硅

电池10.1±0.2公司2微米厚膜二氧化钛纳米电池11.0±0.5EPFL0.25

cm2面积0.27cm2面积USSC公司14.5(初始)±0.712.8(稳定)±0.7非晶硅电池4cm2面积能源公司30.28±1.21.002cm2面积德国20.3±0.5333倍聚光Spectrolab34.7±1.7GaAs多结电池多晶硅 电池InGaP/GaAs96倍聚光SunPower公司26.8±0.8背接触聚光单晶硅电池4cm2面积澳大利亚新南威尔士大学24.7±0.5单晶硅电池备注研制单位转换效率（％）电池种类世界各种

能电池水平各种电池效率的最高水平(STC:AM1.5,1000W/m2,25℃）Si-based

solar

cellsEfficiencyCostsFeedstock

-

availabiltyPurity

requirements

SoG-Si(SoG-Si:

6N

vs.

SEG-Si:

11N)Si-productionELKEMSolar

siliconrsScanSolar

cellsr

ScanCellSolar

cellpanelsSolEnergyResearch

&

educationProduction

of

SoG-Si

solar

grade

siliconQu)artz(SiO2)Carbonprocess

processSoG-Si0.0316025Feedstock

limitationsfrom

EG

scrapNewSoG-SiprocessCurrent

processMetallurgical

Grade

SiliconMG-SiPrimaryPrices

in

US$/kg

SiEG-SiSilicon

forelectronicsQuartz(SiO2)CarbonPrimaryprocessMG-SiSoG-SiDirect

route

to

Solar

Grade

SiSiliconm.p.=1414ºC

b.p.=3265ºCSilicon

Preparation两种多晶硅的

工艺改良西门子法和硅烷法1955年西门子公司研究成功了用H2还原SiHCl3，在硅芯发热体上沉积硅的工艺技术，并于1957年建厂进行工业规模生产。，这就是通常所说的西门子法。随后，西门子工艺的改进主要集中在减少单位多晶硅产品的原料、辅料、电能消耗以及降低成本等方面，于是出现了改良西门子法。该方法所生产的多晶硅占世界生产总量的70~80%。1956年英国国际标准电气公司的标准电讯实验所研究成功了SiH4热分解 多晶硅的方法，被称为硅烷法。1959年的石冢

也同样成功研究出该方法。 联合碳化物公司研究歧化法

SiH4，1980年 最终报告，综合上述工艺并加以改进，诞生了新硅烷法多晶硅生产工艺技术。Silicon

PreparationSynthesis

of

Metallurgical

grade

silicon

(MGS)300oCIn

fluid-bed

reactorSi

+

3HCl

SiHCl3(b.p.

31.8oC)SiO2

+

2C2000oCSi

+

2COMG-Si(metallurgicalgrade

silicon)(>

98%)SiO2

+

C

SiO

+

COSiO

+2C

SiC

+

COSidereactionsSiO2

+

2SiC

3Si

+

2COWith

high[SiO2]+

H2fordistillationFrom

MGS

to

EGS

(electronic

grade

silicon)SiHCl3

+

H21000ºC

Si

+ 3

HClEGS

(>99.9%)processFrom

MGS

to

EGS

(electronic

grade

silicon)改良西门子法流程①SiHCl3的②SiHCl3的精馏提纯③SiHCl3的氢还原④还原尾气回收⑤SiCl4氢化State-of-the-art

of

IC

industryk0≈1

for

B,

P,AsCrystal

growth

Czochralski

processThe

raw

Si

used

for

crystalgrowth

ispurified

from

SiO2

(sand)

throughrefining,

fractional

distillationand

CVD.The

raw

material

contains

<

1

ppbimpurities

except

for

O

(

1018

cm-3)andC

(

1016

cm-3)Essentially

all

Si rs

used

for

ICstoday

come

from

Czochralski

growncrystals.Polysilicon

material

is

melted,

held

atclose

to

1415C,

and

a

single

crystal

seed

isused

to

start

the

crystal

growth.Pull

rate,

melt

temperature

and

rotationrate

are

all

important

control

parameters.The

surface

tension

between

the

seed

and

the

molten

silicon

causes

a

smallamount

of

the

liquid

to

rise

with

the

seed

and

cool

into

a

single

crystalline

ingotwiththe

same

orientation

asthe

seed.The

ingot

diameter

is

determined

by

a

combination

of

temperature

and

extractionspeedCrystal

growth

Czochralski

processExamples

of

completed

ingotsCrystal

growth

Float-zone

processternative

growth

process

is

the

float

zone

process

which

canbeused

for

either

refining

or

single

crystal

growth.In

the

float

zone

process,

dopants

and

other

impurities

tend

to

stayin

the

liquid

and

therefore

refining

can

be plished,

especiallywith

multiple

passes.Crystal

growth

Impurity

segregationEquilibrium

segregation

coefficient:ko=

Cs/ClCs:

the

equilibrium

concentration

of

the

impurity

in

the

solidCl:

the

equilibrium

concentration

of

the

impurity

in

the

meltko

<

1,

implying

that

the

impurities

preferentially

segregateto

the

melt

and

the

melt es

progressively

enrichedwiththese

impurities

as

the

crystal

is

being

pulled.Thin-fiolar

cellCu-In-Ga-Se

(CIGS)CIGS

has

the

highest

demonstrated

efficiency

of

allthin-fi at

19.5%CIGS

can

bedeposited

on

flexible

substratesenabling

lightweight

flexible

modulesNo

inherent

material

limitations

or

hazardouschemicalsRoll-To-Roll

PV

Cell

&

Module

process

FlowRoll

Coater

Manufacturing

SystemFinished

Product16.5%

Efficient

CdTeSolar

CellsPolycrystallineThin

Film

Tandem

Solar

Cell15%

efficient

4-terminal

device

willbe

met1600

PV

cells

in

Sacramento,

CA.

(2

MW

electricity).Part

4:电池Fuel

Cell

DiagramCathodeAnodeO2

inO2/H2O

outH2

inchannelsfor

H2

flowchannelsfor

O2

flowH2/H2O

outH+

or

O2-

conductor(electrolyte)H2

and

O2

never

come

into

contact,

only

H+

and

O2-!!TypeAcronymElectrolyteProton

exchange

membranePEMFCPEMPhosphoric

acidPAFCH3PO4AlkalineAFCKOHMolten

carbonateMCFCCarbonate

SaltsSolid

oxideSOFCYSZTypes

of

fuel

cell:

based

on

kinds

of

electrolyteTypes

of

Fuel

CellsWastefromanodeWastefromcathodeFuel

toanodeOxidizer

(air)toanodeAnode

ElectrolytematerialElectrochemicalreactionin

differenttypesof

FCCathodeMain

advantages

andapplication

of

fuelcellRange

ofapplication

of

thedifferent

types

offuel

cellHigher

efficiencyLess

pollutionQuietPotential

for

zeroemissions,

HigherefficiencyHigher

energydensity

than

batteriesFaster

rechargingMain

advantagePower

inWattsDistributed

powergeneration,

CHP,

alsobusesCars,

boats

anddomesticCHP(Combined

heat

&power)Potable

electronicsequipment( ,

NB,Communication)Typicalapplication1

10

100

1k

10k

100k

1M

10MAFCMCFCSOFCPEMFCPAFCTypes

of

Fuel

CellsProton

Exchange

Membrane

fuel

cells

(PEM):

aka

polymer

eletrodefuel

cells. Use

thin

solid

membrane

as

electrode. High

powerdensity

and

low

weight

compared

to

other

fuel

cells. Can

operateat

relatively

low

temperatures.Alkaline

fuel

cells

(AFCs):

Currently

used

by

space

shuttle

fleet.Use

of

KOH

as

an

electrolyte. Very

efficient

in

space

applicationshowever

susceptible

to

carbon

contamination.Phosphoric-acid

fuel

cells

(PAFCs):

Use

liquid

phosphoric

acid

asthe

electrolyte. Very

efficient

up

to

80%,

but

rather

large

andheavy

and

used

mainly

for

stationary

appilications.Solid

Oxide

(SOFCs):

Use

of

hard

non-pourous

ceramic

compoundas

the

electrode. Very

high

operating

temp

of

around

1800

Ftherefore

require

long

heating

time

but

are

very

efficient.Molten

carbonate

fuel

cell

(MCFC):

Molten

carbonate

fuel

cells

usean

electrolyte

composed

of

a

molten

carbonate

salt

mixturesuspended

in

a

porous,

chemically

inert

cerami

hiumaluminum

oxide

(LiAlO2)

matrix.

These

systems

are

large

andoperate

at

very

high

temperatures

(in

the

range

of

1,200ºF).Durability

is

limited

by

corrosive

electrolyteTypes

of

fuel

cellsCso

be

designated

by

which

fuel

is

used.Hydrogen2

H2

(g)

+

O2

(g)

2

H2O

(g)MethanolCH3OH

(g)

+

O2

(g)

CO2

(g)

+

H2O

(g)PropaneC3H8

(g)

+

5

O2

(g)

3

CO2

(g)

+

4

H2O

(g)Advantages

of

fuel

cellsFuel

(H2

or

hydrocarbons)

is

light

and

can

betransported/refilled.H2

fuel

cells

are

very

efficient

(80%).Fuel

cells

can

be

made

very

tiny.layer

thicknesses

of

m

or

nm

instead

of

mm.can

be

stacked

to

provide

higher

voltage

potential

(V)Power

can

be

increased

by

increasing

fuelflowP

=

IV

so

I

and

V

means

P.Solid

Oxide

Fuel

CellsOxygenOxygenIonsHydrogen

WaterElectron

flowElectrolyteCathode4e-

+

O2

2O2-AnodeH2+O2-H2O+2e-关键材料固体电解质电极材料连接材料材料特性(1)高离子电导(1)高的电子电导率和一定的离子电导率(2)稳定性(3)相容性

(4)催化活性

(5)多孔性(6)足够的机械强度(1)

高纯的率稳定性相容性电子电导率稳定性相容性(4)高的致密度(5)足够的机械强度材料体系(1)YSZ材料

(2)DCO材料掺杂的LaGaO3材料Bi2O3基材料固体质子导体材料镍基、掺杂的氧化铈基阳极和钙钛矿型氧化物阳极La1-xSrxMnO3(LSM)LSM-YSZLa1-xSrxCoO3(LSC)La1-xSrxCo1-yFeyO3d(LSCF)Sm0.5Sr0.5Co3

(SSC)La1-xCaxCrO3(LCC)

、La1-xSrxCrO3(LSC)和Cr-Ni合金等ZrO2基电解质（YSZ）ZrO2

相图加入Y2O3形成稳定立方化ZrO2稳定性，在高温具有足够的离子电导率和可忽略的电子电导，以及高的机械强度σT=800℃=0.03

S

cm‐1Crystal

structures

of

zirconia

(ZrO2)CubicRT1170ºC2370ºCUndopedZrO2:Pure

undoped:

not

interesting

as

a

ceramicCooling

after

sintering:

T

M;Volume

expansion

FractureStabilize

high

temperature

C-phase

to

RT:17

mol%

YO1.5:

stabilizedZrO2;

Ionic

conductorStabilizing

T-phase

to

RT

is

interesting

(TZP)Metastable

T-phase:

high

strength/toughnessMonoclinic

Tetragonal(La,Sr)MnO3（LSM）阴极0.00000.00050.00150.00206.05.25.04.24.0x=0x=0.1x=0.2x=0.3x=0.4x=0.7x=0.5log[T

(S

cm-1K)]0.0010T-1/K-11-x

xLa Sr

MnO3+O2P =1

barLSM表面交换系数和氧扩散系数Ni-YSZ复合阳极1010-210-1100104103102101Conductivity

(S

cm-1)Toyo

SodapowderZircar

powder6020

30

40

50Ni

content

(vol%)热膨胀系数、孔隙率、TPB的扩散程度（电化学性能）、长期性能PVI曲线（湿H2+O2）Journal

of

SolidState

Electrochemistry

13(12):

1905‐1911Nature,

414(2001)

345‐352电解质薄膜化高性能阴极难点一：SOFC低温化OxygenOxygenIonsElectron

flowElectrolyteCathode4e‐

+

O2

2O2‐Bio‐Gas(CO

+

H2

+

CH4)

+

O2‐CO2

+

H2O

+

e‐AnodeBio‐gasH2O

+

CO2难点二：生物质难点三：大功率电池堆Hydrogen-Oxygen

Fuel

Cell

with

Alkali

or

PhosphoricAcid

ElectrolyteH2O2LoadanodecathodeH2

+

2OH-

=2H2O

+

2e-H2O2LoadanodecathodeH2

=

2H+

+

2e-OH-OH-OH-

OH-H+H+H+H+

+

OH-

=H2OH+H+

+

OH-

=

H2O22H+

+

2e-

+

1/2O

=H2O2

2H

O

+

2e-

+

1/2O

=2OH-AFC

PAFCMolten

CarbonateFuel

CellsOperation

Temperature:

650

degrees

CElectrolyte:

Salt

CarbonatesFuel:

Syngas

or

Hydrogen,

andAdditional: CO2

due

to

CO3

ion

usageCatalyst:

NickelPower

output:

~2MW

units

availableMolten

CarbonateFuel

CellsA

Proton

Exchange

Membrane

(PEM)

fuel

cellPEM

Fuel

CellsOperation

Temperature:

100

degrees

CElectrolyte:

PolymerFuel:

HydrogenCatalyst:

PlatinumPower

output:

50-250

kW

units

availablePEM

Fuel

CellsThe

Homo-heterogeneous

Nature

in

PEM

ElectrolytePorous

NafionH2H2OCF2OCF2CF2SO

-H+3CF2SO

-H+3OCF2CF23SO

-H+SO

H+3-CF2CF2OSO3-H+CF2CF2OAnodePorousACCathodePorousACH+H+PtO2Oad2H

Oe-HHOHHOHHOHHOOH

HH

HOH

HOH

HPtOHHe-HadH+

O(CF2CF2)(CF2CF)x

(Nafion)OHHHOHOH

HPt

clusters

on

cloth

of

porous

conducting

carbon,Loading

of

Pt:

~

30

g

m-2(Nafion)Solid

polymer

based

on

perfluoronsulphonic

acidMembrane

electrode

assembly

(MEA)EcoFC

available

in

1

to

6-cell

versions,

generates

3.5

to

19

watts

at

0.6

to

3.6

V.

Although

the

output

voltageincrements

are

the

same

as

LightFC

more

power

is

available

because

the

membrane

electrode

assembly

in

thefuel

cell

has

a

larger

active

area(roughly

14.5

square

centimetres)ECOFC-5

is

a

five

cell

stack

providing

16W

at

3V

off

hydrogen

and

oxygen.639.00EUR

Retail

Price:Commercial

MEA

for

PEMFCDirect

Methanol

Fuel

Cell

(DMFC)Probably

the widely

commercialized

typeCH3OH

+

H2O質子交換膜3/2

O2—

＋CO21.18

Ve-e-3H2OHigh

TemperatureSolid

State

Proton

ConductorsApplicationsFuel

cellsDehydrogenation

pumpselectrolyzersSensors

(H2O,

H2)Mixed

Proton

Electron

Conductorsas

hydrogen

separation

membranesNatural

gas

to

syngasHydrogen

extractionFuel

Cells

for

Mobile

PlatformsPhoto

showing

conceptual

Motorola/LANL

fuel-Superior

to

batteries

at

100

Watt-hr

(Metal

hydride)Fuel

cell

technology

improves

at

approx.

10watt-hr/yrParity

withlaptop

batteries

in

5

Yearss

(2-5

Watt-hr)

soon

to

follow

(anotherMotorola/LANL

collaborationDirect

MethanolBattery-FC

hybrid

(FC

at

1

Watt

chargSame

form

factorPower

phones

for

over

amonth?Replacable

cartridge

to

feed

fuel,

collect

water...Stationary

vs.

portable

systems-

important

issues

and

technical

requirementsPortableEnergy

density

of

fuelCompactness

and

weightDynamic

operation/transients/response

timeBuffer

or

batteryNo

run-away

reactionsFleet

vs

“private”Hydrogen

fuel

used

in

PEM

(proton-exchange

membrane)

cellsfor

vehicles.a)

Toyota

Prius

hybrid,

b)

Engine

of

PriusHydrogen

as

energy

carrierH2

+

1/2O2

H2OChemical

energy

heat

electrical

energyProductionProductionStorageUseGas;

reformingSynthesis

gasPyrolysisElectrolysisPhotolysisPressurized

gasLiquidSolid

absorbersFuel

cellsCombustionHydrogen

societyMaterial

challengesCatalystsAlloys

for

reactorsMetal

hydridesCarbonMicroporousmaterialsFuel

cellsMembranesCatalystsHydrogen

storage

materialsMetal

hydride

forming

elements”Rule

of

2

Å”

for

H-H

separationHigh

H-mass

densityHigh

H-volume

densityAppropriate

p,T

stabilityReversible

absorption/desorptionmetal

hydridescarbon

based

materialsmicorporous

materials‘‘The

2Å

r