羅燚, 馮軍宗, 馮堅, 姜勇剛, 李良軍

新型碳材料質子交換膜燃料電池Pt催化劑載體的研究進展

羅燚, 馮軍宗, 馮堅, 姜勇剛, 李良軍

(國防科技大學 空天科學學院, 新型陶瓷纖維及其復合材料重點實驗室, 長沙 410073)

質子交換膜燃料電池(PEMFC)具有能量轉換效率高、功率密度大、室溫啟動快、噪音低和零污染等特點, 有望減少二氧化碳排放量, 緩解能源危機, 在軌道交通、航空航天等領域具有廣闊的應用前景。催化劑是PEMFC的關鍵材料, Pt催化氧還原反應活性和穩(wěn)定性好, 是廣泛使用且很難被取代的電催化劑。然而Pt儲量低、價格昂貴, 導致PEMFC成本較高, 使用Pt載體可減少PEMFC的Pt負載量, 提高Pt利用率。碳材料具有成本低廉、比表面積大、孔結構豐富、電導率和表面性質可調等特性, 是廣泛應用的Pt載體。商用的炭黑載體對Pt的利用效率低, 抗電化學腐蝕性較差。為了進一步提高PEMFC的性能和持續(xù)性, 需要研發(fā)能夠均勻負載Pt、高效利用Pt、抗電化學腐蝕性強且導電性好的碳載體, 進而實現(xiàn)PEMFC的大規(guī)模應用。炭氣凝膠、碳納米管和石墨烯等新型碳載體具有獨特的結構和性質, 可以提高PEMFC性能和壽命, 引起了研究者的廣泛關注。本文對近年來PEMFC新型碳材料Pt載體的研究進展進行了較為詳細的綜述, 并對其發(fā)展趨勢作出了適當評論。

質子交換膜燃料電池; 炭氣凝膠; 碳納米管; 石墨烯; 綜述

面對化石能源日益減少的現(xiàn)狀, 人類社會迫切需要開發(fā)綠色、環(huán)保和高效的新能源。質子交換膜燃料電池(PEMFC)具有能量轉換效率高、功率密度大、室溫啟動快、噪音低和零污染等特點, 在軌道交通、航空航天等領域具有廣闊的應用前景[1-4]。PEMFC系統(tǒng)的核心部件為膜電極, 由氣體擴散層、催化劑層和質子交換膜組成[5-6], 如圖1所示。Pt催化氧還原反應活性和穩(wěn)定性好, 是在PEMFC中被廣泛使用且很難被取代的電催化劑。然而, Pt在地殼中的儲量稀少, 阻礙了PEMFC的大規(guī)模生產應用。催化劑載體能夠降低PEMFC中Pt的用量[7], 是實現(xiàn)PEMFC商業(yè)化應用的途徑之一。

圖1 PEMFC的組成結構示意圖[6]

PEM: Proton exchange membrane; MEA: Membrane electrode assembly; GDL: Gas diffusion layer; CL: Catalyst layer

載體是PEMFC中非常重要的組成部分, 直接影響催化劑的粒徑大小、分布、電化學活性比表面積、穩(wěn)定性和利用率, 最終影響PEMFC的性能和壽命[8-9]。PEMFC中反應物、產物、電子以及質子傳輸效率和速度也與載體性質密切相關[10-13], 并且載體與催化劑協(xié)同效應能夠提高催化劑性能[14-15]。好的載體主要具備[16-20]: (1)高的活性比表面積, 能夠均勻負載催化劑; (2)合適的孔結構, 能提供高活性三相反應界面; (3)較強的穩(wěn)定性, 在高濕、高電壓等苛刻條件下, 長時間不發(fā)生嚴重電化學腐蝕; (4)高電導率。以上條件之間存在矛盾或依賴的關系: (1)比表面積與孔結構有關, 電導率與結晶度有關; (2)高電導率載體的穩(wěn)定性好; (3)中孔結構有利于負載催化劑, 但大量中孔結構的載體, 穩(wěn)定性往往較差。理想載體能夠搭建高效電催化反應界面、錨定催化劑納米粒子、減緩催化劑失活, 延長PEMFC壽命、提升性能、降低成本。

炭黑是商品PEMFC的主要載體。美國Cabot公司生產的 Vulcan XC性能較好, BET 比表面積約為250 m2?g–1, 中孔和大孔達 54% 以上, 電導率2.77 S/cm, 基本滿足電催化劑載體對比表面積和導電性的要求, 是目前應用最為廣泛的商品載體。

然而, 炭黑的缺點之一是結構中微孔含量較高[21]。Thommes等[22]研究表明, 導電高聚物無法進入微孔, 陷入炭黑微孔中的Pt實際上沒有參與電催化反應過程。因而, 炭黑負載Pt利用率較低。同時, Maillar等[23]研究發(fā)現(xiàn), 分散在炭黑表面的Pt雖能夠參與反應, 但在催化過程中容易發(fā)生溶解、團聚和位置轉移等失活行為, 如圖2所示。炭黑抗電化學腐蝕性也較差[24], 炭黑的常溫電化學腐蝕熱力學電壓(0.203 V. NHE)低于PEMFC的工作電壓(>0.6 V. NHE)。提高炭黑的石墨化程度雖能夠降低電化學腐蝕速率[25], 但很難在熱力學上避免發(fā)生腐蝕。Tuaev等[26]研究了碳載體孔結構對催化劑活性的影響, 發(fā)現(xiàn)中孔結構有利于阻止Pt失活。炭黑的抗電化學腐蝕性和孔結構均存在一定的缺陷, 較難滿足理想電催化劑載體的條件。由圖3可知炭黑在電化學腐蝕前后, 結構發(fā)生了明顯的改變[27]。

近年來對碳載體的研究主要集中在新型碳載體的開發(fā)和利用上: 炭氣凝膠具有可控的孔結構, 可根據(jù)應用需要, 設計孔性質; 碳納米管和石墨烯具有低阻抗、高導電性和高電化學穩(wěn)定性等優(yōu)異性質。新型碳載體有望克服炭黑的缺點, 是很有潛力的PEMFC載體材料。本文主要綜述了近年來研究者在炭氣凝膠、碳納米管和石墨烯等新型碳載體上的研究進展。

圖2 Pt納米粒子在炭黑載體上的失活示意圖[21]

圖3 炭黑電化學腐蝕前(a)后(b)的原子力顯微鏡照片[27]

1 炭氣凝膠

炭氣凝膠是一種非晶態(tài)碳材料,其納米多孔三維網(wǎng)絡結構可控(圖4), 具有高比表面積(600~ 1100 m2?g–1)、高孔隙率(80%~98%)和高穩(wěn)定性[28]的特點。載體孔結構對PEMFC非常重要, 合適的孔結構有利于傳質和阻止Pt失活。通過調控炭氣凝膠的孔結構有望制備出滿足PEMFC要求的載體。

為研究孔結構對PEMFC性能的影響, Ouattara等[29]制備出具有不同孔徑分布的炭氣凝膠。由圖5可知, 載體孔徑在25~30 nm時, PEMFC性能最佳; PEMFC的傳質阻力主要依賴于炭氣凝膠孔結構, 孔徑大于40 nm時, 導電高聚物易堵塞孔結構, 增大傳質阻力。Smirnova等[30]研究表明, 炭氣凝膠孔徑由16 nm增大到20 nm, 電池性能逐步增強; 孔徑20 nm的炭氣凝膠負載0.1 mg?cm–2Pt時, 達到最大功率密度800 mW?cm–2。合適的載體孔結構有利于減小傳質過程導致的功率損失。Ouattara等[31]針對如何更好地調控膜電極的水, 設計了三維多孔炭氣凝膠載體, 0.4 V電壓下電池功率提高了40%。Wang等[32]發(fā)現(xiàn)N摻雜梯度孔炭氣凝膠有利于傳質, 摻雜微量Fe元素后, 催化氧還原活性非常好, 起始電壓和半波電壓分別為918和798 mV,比相同條件下Pt/C催化劑分別高出117和206 mV。

在PEMFC的使用過程中, 啟動、急停都會加速碳載體的電化學腐蝕。Ouattara等[33]模擬PEMFC的啟動和急停條件, 加速老化測試炭氣凝膠抗電化學腐蝕性能, 相同條件老化14 h后, Pt/C和Pt/炭氣凝膠活性比表面積分別減少了17.57%、56.27%。炭氣凝膠由于石墨化程度較低, 抗電化學腐蝕性比Pt/C催化劑要差。為了提高炭氣凝膠石墨化程度, Singh等[34]通過高溫高壓凝膠、高溫惰性氣氛石墨化, 制備出中孔比表面積490 m2?g–1、平均孔徑4.9 nm的炭氣凝膠, PEMFC的起始電位為964 mV, 半波電位為814 mV, 優(yōu)于相同條件下Pt/C催化劑。

炭氣凝膠上存在許多活潑碳懸空鍵, 比較容易發(fā)生電化學腐蝕反應。炭氣凝膠表面改性可提高抗電化學腐蝕性和催化活性。Wang等[35]制備了KOH活化摻N炭氣凝膠催化劑, 摻雜N引入了大量的缺陷結構, KOH活化后進一步優(yōu)化了炭氣凝膠的孔結構, 無需負載Pt, 催化氧還原反應半波電壓為790 mV。Fabien等[36]在炭氣凝膠表面涂覆SnO2載體的抗電化學腐蝕性較好, 加速氧化測試后負載催化劑的活性比表面積和質量比活性不降反增; 由圖6可知, 相比于炭氣凝膠而言, SnO2涂覆炭氣凝膠負載Pt催化劑加速氧化測試后, Pt粒子團聚現(xiàn)象減少。強氧化劑與炭氣凝膠懸空鍵結合, 有利于在動力學上減緩電化學腐蝕。Berthon等[37]制備了氟化炭氣凝膠, 5×103次循環(huán)測試后氟化載體催化劑活性比表面積僅減小10%, 遠低于相同條件下Pt/炭氣凝膠(25%)和Pt/C(15%)。

圖4 炭氣凝膠CA20(a)、CA30(b)和CA40(c)的SEM照片[28]

圖5 壓汞法測定的不同固含量、不同間苯二酚(R)和碳酸鈉(C)摩爾比的炭氣凝膠孔徑分布曲線(a), 及其對應的單電池極化曲線(b)[29]

圖6 炭氣凝膠(a)及SnO2涂覆炭氣凝膠(b)負載Pt催化劑加速氧化測試(AST P1)后的TEM照片和加速氧化測試前后的Pt粒子統(tǒng)計分布圖[36]

炭氣凝膠具有中孔比表面積高、活性位點多、傳質阻力小等特點, 非常適合作為PEMFC載體?？煽氐募{米多孔三維網(wǎng)絡結構是炭氣凝膠作為載體最具有吸引力的特點。然而, 炭氣凝膠目前存在抗電化學腐蝕性較差等缺點。表面改性、提高石墨化程度是增強炭氣凝膠抗電化學腐蝕性的主要方法。目前, 以炭氣凝膠為載體的PEMFC正處于應用前期。

2 碳納米管

碳納米管是呈六邊形排列的碳原子層構成的無縫管, 是一種特殊的一維納米結構, 具有阻抗低、導電性高、穩(wěn)定性好的特點。根據(jù)管壁中碳原子層數(shù)目, 碳納米管可分為單壁碳納米管和多壁碳納米管[38], 結構如圖7所示。很多研究[39-42]表明, Pt/碳納米管電催化活性、抗電化學腐蝕性和抗CO毒性均優(yōu)于同條件下的Pt/C, 是很有潛力的載體材料。近年來, 研究者在增強碳納米管負載催化劑的穩(wěn)定性、增大碳納米管比表面積等方面開展了深入的研究。

Pt與碳納米管摻雜的雜原子之間的電子轉移可增強催化活性。Zhao等[43]制備了含F(xiàn)e的N摻雜碳納米管, 催化氧還原反應半波電壓為850 mV, 密度泛函理論模型研究表明結構中大量的吡啶N加快了電子傳遞速度。二氧化鈦穩(wěn)定性較好、具有一定催化活性, Mohammad等[44]合成了一種TiSi2O涂覆碳納米管, 負載Pt后催化氧還原反應, 半波電壓比Pt/碳納米管高出30 mV。Gao等[45]研究表明, 利用高度分散晶體Ta2O5修飾的碳納米管作為載體, 穩(wěn)定性非常好、催化活性也較好, 104次循環(huán)伏安測試之后, 半波電壓和活性比表面積基本不發(fā)生變化, Pt?Ta2O5/碳納米管電化學活性比表面積為78.4 m2?g?1, 0.9 V時的質量比活性為0.23 A?mg?1Pt, 是相同條件下Pt/C和Pt/碳納米管的2.2和3.4倍。Ta2O5和碳納米管協(xié)同作用, 改變了Pt電子結構, 形成了Pt–O–Ta化學鍵, 使得Pt變得更加穩(wěn)定。

為增大碳納米管比表面積, Sahoo等[46]將多層碳納米管上層沿軸向打開, 制備出了具有石墨烯“翅膀”的石墨烯–碳納米管雜化材料。研究結果表明, 相比于Pt/C催化劑, Pt/石墨烯–碳納米管雜化材料具有高催化活性, 陰極Pt負載量為0.3 mg?cm–2時, 最大功率密度高達1000 mW?cm–2。石墨烯–碳納米管雜化材料兼具石墨烯片層和碳納米管一維結構, 電導率高、反應活性位點多, 碳納米管和石墨烯片層協(xié)同作用有利于Pt分散, 是一種新型載體材料。Priji等[47]研究了Pt-Sn/石墨烯–碳納米管載體催化劑, 當Pt、Sn原子比為3 : 1時, 60 ℃功率密度為568 mW?cm–2, 比同等條件下Pt/碳納米管高出23%且陰極催化劑負載量遠低于性能相當?shù)腜t/C。Meenakshi等[48]報道了具有高活性和穩(wěn)定性的Pt3Sc/石墨烯–碳納米管催化劑, 60 ℃時的功率密度為760 mW?cm–2, 加速氧化測試前后的質量比活性均高于Pt/C。

圖7 碳納米管原子結構示意圖(a~c), 隧道電子顯微鏡照片(d), TEM微觀形貌照片(e)[38]

碳納米管的導電性和穩(wěn)定性優(yōu)異, 抗電化學腐蝕性較好。然而, 碳納米管的活性比表面積較小, 表面惰性導致負載Pt催化劑能力較弱。近年來, 研究者們通過制備碳納米管雜化材料、碳納米管–過渡金屬復合材料等方法, 極大地增強了碳納米管負載Pt催化劑的催化活性和穩(wěn)定性, 增大了碳納米管載體的活性比表面積, 增強了Pt負載能力。但是對于工業(yè)化生產, 碳納米管作為PEMFC催化劑載體還面臨著合成方法和價格的問題。

3 石墨烯

石墨烯具有二維平面結構, 其理論比表面積大(2630 m2?g–1)、電導率高(106 S?cm–1)、抗電化學腐蝕性好[49], 是很有應用前景的PEMFC載體材料。大量研究表明, 以石墨烯作為Pt、Pt合金和非貴金屬催化劑載體的催化劑, 性能均優(yōu)于商業(yè)Pt/C。

石墨烯具有諸多優(yōu)異性能, 但其本征二維結構的片層間范德華力較強, 容易發(fā)生重組、團聚, 導致負載的Pt隨之團聚、脫落和失活。通過二維片層石墨烯架構而得到的具有三維結構的石墨烯材料, 能避免片層間團聚。Liu等[50]制備了具有三維結構和缺陷的石墨烯泡沫, 比表面積高達1500 m2?g–1, 載體催化劑的電化學活性比表面積為101 m2?g–1(比Pt/C高50%), 質量比活性為176 A?g–1Pt(比Pt/C高30%)。石墨烯氣凝膠具有本征納米多孔三維網(wǎng)絡結構。Eylul等[51]使用超臨界CO2溶劑將Pt負載在石墨烯氣凝膠上, 載體催化劑電化學活性比表面積為102 m2?g–1, 質量比活性為30.6 A?g–1Pt。

以炭黑為阻隔和連接石墨烯片層的“空間橋梁”, 形成具有三維結構的石墨烯–炭黑雜化材料, 能夠阻止石墨烯片層團聚[52-54]。Li等[55]使用聚苯并咪唑將炭黑和石墨烯片層結合, 制備炭黑–石墨烯雜化材料, 研究表明以這種材料為載體的催化劑, 質量比活性為183 A?g–1Pt(Pt/C為149 A?g–1Pt), 膜電極開始工作后, 最大電流密度由500 mA?cm–2增大到2250 mA?cm–2; 由圖8可知, 1000次循環(huán)伏安測試之后, 電流密度保持在1500 mA?cm–2, 峰電壓為1.0~1.5 V, 而Pt/C峰電壓值降低為0 V。聚苯并咪唑可錨定Pt, 且石墨烯抗電化學腐蝕性較好, 故而炭黑–石墨烯載體性能優(yōu)異。除炭黑之外, 碳納米管、碳纖維等也可以作為阻隔并連接石墨烯片層的“空間橋梁”[56-61]。

圖8 商業(yè)Pt/C(a), Pt/炭黑–石墨烯雜化材料(b)為陰極催化劑的PEMFC經加速氧化測試后的極化曲線; 不同循環(huán)次數(shù)后的電壓保留值(c)[55]

石墨烯表面呈化學惰性, 活性位點少, 負載催化劑能力較弱, 在石墨烯表面加入雜原子、官能團或大分子, 能夠在平面引入具有電化學活性的缺陷結構, 增大活性比表面積, 增強催化活性[62-64]。Sergey等[65]制備了摻氟、摻氧的氧化石墨烯, 摻氧氧化石墨烯負載的Pt顆粒粒徑較小, 摻氟、摻氧石墨烯載體催化劑性能均高于Pt/C。

近年來, 研究者們在雜原子摻雜石墨烯作為非貴金屬催化劑載體, 用于催化氧還原做了大量工作[66]。氮摻雜石墨烯增加了每摩爾氧氣的電子轉移數(shù), 使氧氣能在低電壓下形成OH–。Xu等[67]研究了Co–B–N摻雜多孔石墨烯催化劑的電化學活性, 起始電位和半波電位分別為904和792 mV, 僅比商業(yè)Pt/C催化劑低0.06和0.04 V, 而Tafel斜率為58?mV?dec?1, 低于Pt/C(71?mV?dec?1)。Lei等[68]研究報道了N摻雜石墨烯氣凝膠用于氧還原反應, 起始電壓僅比相同條件下Pt/C低0.1 V, 穩(wěn)定性和對甲醇的耐受性好于Pt/C。同時, Wang等[69]還通過研究表明, 石墨烯上吡啶N摻雜缺陷處催化氧還原活性較高, 產生的超電勢最低為0.28 V, 大量吡啶N缺陷摻雜石墨烯在堿性環(huán)境中半波電位為850 mV, 催化活性較好。Yang等[70]設計摻Fe、摻N單層石墨烯為氧還原催化劑, 揭示了催化反應活性位點為Fe與吡啶N結合的缺陷位置。

石墨烯電導率高、抗電化學腐蝕性好且比表面積大。然而, 其在使用過程中易團聚、表面呈化學惰性。制備具有三維結構的石墨烯可以阻止片層團聚; 雜原子摻雜石墨烯, 可在表面引入具有催化活性的缺陷結構, 調節(jié)缺陷數(shù)目、尺寸和形狀等, 改善石墨烯表面活性, 增強其負載能力和催化活性。單獨的石墨烯片層較難在PEMFC中應用, 而三維結構的石墨烯材料和原子雜化石墨烯具有非常優(yōu)異的性能, 有望成為PEMFC載體。

4 其他新型碳材料

碳纖維具有優(yōu)異的導電性和獨特的物理化學性質, 是一種很有潛力的電催化劑載體。Wang等[71-73]研究了氮摻雜多孔碳纖維、中空多孔碳纖維等不同形態(tài)的碳纖維, 多孔碳纖維負載Pt的抗電化學腐蝕性和催化活性均優(yōu)于Pt/C, 電化學活性比表面積為52 m2?g–1(Pt/C為41 m2?g–1), 起始電壓和半波電壓分別為891和739 mV, 比Pt/C分別高出44和25 mV; 其最大功率密度為130 mW?cm–2, 是同等條件下Pt/C的二倍。Song等[74]制備了一種直徑100 nm、孔徑5~30 nm的超細多孔碳納米纖維負載的Pt催化劑, 電化學活性比表面積為71.9 m2?g–1(Pt/C 為54.6 m2?g–1), 起始電位和半波電位分別為969和763 mV均高于Pt/C, 功率密度為165 mW?cm–2, 是Pt/C的1.25倍。

空心碳表面具有有序的介孔結構、內部中空, 電導率在0.003~1.4 S?cm–1之間。Ying等[75]合成了Co–Pt二元合金催化劑, 并將其植入氮摻雜的空心碳中, 相同條件下質量比活性是Pt/C的13.5倍, 電化學活性比表面積為64.6 m2?g–1(Pt/C為57.6 m2?g–1), 半波電位為883 mV(Pt/C為864 mV), 加速氧化測試之后半波電位僅降低19 mV(Pt/C降低67 mV), 催化活性和耐久性都較好。Chen等[76]制備了氮摻雜石墨碳負載微量Co催化劑, 微孔、介孔結構和摻雜石墨N、吡啶N使得材料具有催化氧還原活性。

近年來研究表明, 碳纖維、空心碳等新型碳材料作為電催化劑載體性能優(yōu)異, 但由于制備方法復雜, 難以工業(yè)化生產和大規(guī)模應用, 成本較高, 故而研究較少。

5 結語

炭黑是商業(yè)PEMFC中被廣泛使用的Pt載體, 性能基本滿足要求, 但微孔含量高、導電性較差、比表面積較小, 易發(fā)生電化學腐蝕、催化劑利用率低, 導致PEMFC性能持續(xù)性較差。通過研發(fā)具有特殊結構和優(yōu)異性能的新型碳載體, 有望克服炭黑載體的缺點。

炭氣凝膠具有可控的納米多孔網(wǎng)絡結構, 活性比表面積大, 能夠均勻有效地負載Pt、緩解Pt失活、降低傳質阻力, 然而抗電化學腐蝕性較差。表面改性和增強結構中石墨化程度, 是提高炭氣凝膠抗電化學腐蝕性的有效措施。碳納米管導電性和穩(wěn)定性好, 抗電化學腐蝕性較好, 然而比表面積較低, 負載Pt能力較弱。碳納米管雜化材料、碳納米管–過渡金屬復合材料極大地增大了碳納米管載體的活性比表面積和負載Pt的能力。石墨烯電導率高、抗電化學腐蝕性好且比表面積大。然而, 其在使用過程中易團聚、表面呈化學惰性。制備三維結構石墨烯可以阻止片層團聚; 雜原子摻雜石墨烯, 可在表面引入具有催化活性的缺陷結構, 增強其負載能力和催化活性。本文綜述的各類碳載體優(yōu)缺點, 總結如表1所示。

PEMFC要求載體有大量的三維互通中孔結構、豐富的表面活性位點、具有高導電性和穩(wěn)定性的特點, 同時能夠大規(guī)模工業(yè)化生產。具有豐富中孔結構的高度石墨化炭氣凝膠、改性炭氣凝膠、三維結構石墨烯材料、高比表面積碳納米管雜化材料等, 理論上滿足大多數(shù)理想電催化劑載體的條件, 性能較好, 有望成為新一代PEMFC電催化劑載體。

表1 不同碳載體的性能比較

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Research Progress on Advanced Carbon Materials as Pt Support for Proton Exchange Membrane Fuel Cells

LUO Yi, FENG Junzong, FENG Jian, JIANG Yonggang, LI Liangjun

(Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace and Engineering, National University of Defense Technology, Changsha 410073, China)

Proton Exchange Membrane Fuel Cell (PEMFC) has the characteristics of high energy conversion efficiency, high power density, fast start-up at room temperature, low noise and zero pollution, which is expected to alleviate the energy crisis and reduce carbon dioxide emissions. It has broad application prospects in rail transit, aerospace and other fields. Catalyst is one of the key materials of PEMFC. Moreover, Pt catalysts are widely used and considered difficult to be replaced because of their good activity and stability in oxygen reduction reaction. Pt is expensive because of its limited storage. However, Pt loading could be significantly lessened by Pt support to improve PEMFC utilization. Carbon materials are widely used as Pt supports because of their low cost, high specific surface area, pore structure, adjustable conductivity and surface properties, but commercial carbon black supports have low utilization efficiency and poor electrochemical corrosion resistance for Pt. For realizing the large-scale application of PEMFC, it is necessary to develop new carbon supports which can uniformly disperse Pt, efficiently utilize Pt, be resistant to electrochemical corrosion, and have good conductivity, thus the performance and sustainability of PEMFC are improved. Carbon aerogels, carbon nanotubes, graphene and other new carbon supports with unique structures and properties, which are expected to improve PEMFC performance and life, have attracted the attention of many researchers. In this paper, the research progress on new carbon material as Pt support for PEMFC in recent years is reviewed systematically, and the development trend is also commented appropriately.

Proton Exchange Membrane Fuel Cell; carbon aerogel; carbon nanotube; graphene; review

TQ15

A

1000-324X(2020)04-0407-09

10.15541/jim20190169

2019-04-22;

2019-08-03

國家自然科學基金(51172279, 51302317, 51702360) National Natural Science Foundation of China (51172279, 51302317, 51702360)

羅燚(1994–), 男, 博士研究生. E-mail: nudtluoyi@163.com

LUO Yi(1994–), male, PhD candidate. E-mail: nudtluoyi@163.com

馮堅, 研究員. E-mail: fengj@nudt.edu.cn

FENG Jian, professor. E-mail: fengj@nudt.edu.cn