改性Cu2O光催化劑的研究進(jìn)展

高　鑫，劉祥萱，王煊軍，朱左明

(1 第二炮兵工程大學(xué)，西安 710025；2 第二炮兵裝備研究院，北京 100085)

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改性Cu2O光催化劑的研究進(jìn)展

高鑫1，劉祥萱1，王煊軍1，朱左明2

(1 第二炮兵工程大學(xué)，西安 710025；2 第二炮兵裝備研究院，北京 100085)

介紹了Cu2O光催化劑的電子性能和結(jié)構(gòu)性能，重點討論了Cu2O的金屬/非金屬離子和半導(dǎo)體復(fù)合(包括MxOy/Cu2O和MxSy/Cu2O型)改性研究進(jìn)展，論述了Cu2O光催化劑穩(wěn)定性的研究現(xiàn)狀，對未來Cu2O改性研究進(jìn)行展望，認(rèn)為應(yīng)從制備技術(shù)、表征手段和二次污染方面入手，并著重在改性機(jī)理和性能評估方面加強(qiáng)研究。

Cu2O；光催化；改性；穩(wěn)定性

廢水中的污染物結(jié)構(gòu)復(fù)雜、性質(zhì)穩(wěn)定，常規(guī)處理方法如物理、化學(xué)、生物法不能完全將其去除[1]。高級氧化法是目前去除廢水中有機(jī)污染物的主要方法，具有很強(qiáng)的氧化性能，但相對復(fù)雜、化學(xué)品消耗大、處理成本較高[2]。光催化技術(shù)作為一種行之有效的方法對環(huán)境污染物具有較好的處理效果，成為廢水處理研究的熱點。

TiO2和ZnO是目前最常用的光催化劑，但二者禁帶寬度在3.0～3.2eV之間，僅能在紫外光照射下激發(fā)，只有不到5%的太陽能被利用[3-7]。而P型半導(dǎo)體Cu2O禁帶寬度僅為2.17eV左右，在可見光范圍內(nèi)被激發(fā)，已經(jīng)廣泛應(yīng)用于光催化降解廢水、分解水制備H2、太陽能電池、氣敏傳感器等[8-11]。另外，Cu2O無毒，制備成本低，儲量豐富，是一種非常有潛力的光催化材料。Cu2O的理論太陽能利用率為14%～20%左右，但是已報道的僅為2%[12,13]。此外，Cu2O光催化效果不高，主要原因如下：一是光引發(fā)的電子-空穴對很容易復(fù)合[14,15]；二是Cu2O不穩(wěn)定[16,17]，較容易在空氣中和液相中被氧化或還原。為了解決以上問題，對Cu2O進(jìn)行改性已經(jīng)成為目前的研究熱點。美國Laser Dynamics實驗室合成了Cu2O-Au復(fù)合物，利用飛秒發(fā)射探針技術(shù)追蹤C(jī)u2O-Au納米結(jié)構(gòu)中載流子壽命，發(fā)現(xiàn)載流子壽命隨Cu2O殼厚度的增加而增加，但是當(dāng)沒有Au時載流子壽命縮短[18]。Zhang等將Cu2O納米線覆以C層保護(hù)，20nm厚的C層能使Cu2O在1200s照射后光電流密度僅衰減19.7%(無C層保護(hù)衰減量為87.4%)，穩(wěn)定性提高600%[19]。

近年來，關(guān)于Cu2O光催化劑的綜述不在少數(shù)，但是專門就Cu2O改性研究的綜述報道較少，因此，本文從離子改性和半導(dǎo)體復(fù)合兩個方面敘述了Cu2O改性的研究現(xiàn)狀，介紹了Cu2O光催化過程中的穩(wěn)定性，并對其研究方向進(jìn)行了展望。

1　Cu2O電子與結(jié)構(gòu)性能

Cu2O常溫下很穩(wěn)定，加熱到1800℃時才發(fā)生分解，反應(yīng)如下：

2Cu2O→4Cu+O2

(1)

室溫下空氣干燥時，Cu2O本身是穩(wěn)定的，但當(dāng)空氣中有水分時很容易被氧化，形成黑色CuO：

2Cu2O+O2→4CuO

(2)

Cu2O晶體結(jié)構(gòu)為赤銅礦型，赤銅礦結(jié)構(gòu)為簡單立方Pn3m空間群，屬等軸晶系。Cu2O是一種典型的金屬缺位P型半導(dǎo)體，Cu3d和O2p的軌道雜化以及晶體結(jié)構(gòu)內(nèi)部的Cu2 +缺陷，顯著提高了空穴的導(dǎo)通性，因此具有良好的光催化性能[20]。

2　Cu2O的改性

Cu2O改性主要針對以下三方面：(1)改性后使其具有合適的導(dǎo)帶/價帶邊緣電勢；(2)增加載流子的流動性，阻止電子-空穴對的復(fù)合；(3)減少光蝕，提高Cu2O的穩(wěn)定性。

2.1離子改性

2.1.1金屬離子改性

合理的金屬離子改性可使Cu2O吸收光譜范圍[21,22]拓展、抑制電子-空穴的復(fù)合以提高光催化反應(yīng)的量子效率[22-24]，增強(qiáng)Cu2O對目標(biāo)反應(yīng)物的吸附，從而提高其光催化性能。改性的金屬離子種類包括Au[22,25,26],Ag[27-30],Zn[31],Cu[32-34],Pt[35]等。

2.1.1.1金屬離子改性機(jī)理

金屬摻雜的Cu2O在光照激發(fā)后產(chǎn)生電子(e-)-空穴(h+)對，由于金屬-半導(dǎo)體界面的肖特基勢壘作用，金屬作為電子接收器，e-從半導(dǎo)體導(dǎo)帶轉(zhuǎn)移至改性的金屬上，h+則留在半導(dǎo)體表面[36,37]，延長電子-空穴的復(fù)合時間，這樣e-和h+再分別作用產(chǎn)生具有較強(qiáng)氧化性的OH·，提高光催化性能[22]，原理如圖1所示。此外，貴金屬納米顆粒的等離子體激元共振效應(yīng)能夠增加入射光子的吸收，拓展Cu2O的光譜吸收范圍[38]。

圖1　金屬改性的Cu2O中電子-空穴傳遞路徑Fig.1　Vectorial transfer of electrons-holes (e-/h+) in metal doped Cu2O

Au改性的Cu2O異質(zhì)結(jié)構(gòu)中由于Au顆粒良好的導(dǎo)電性使Cu2O表面的光引發(fā)電子快速轉(zhuǎn)移，從而實現(xiàn)電子-空穴分離[39]，此外，Au,Ag等貴金屬顆粒改性產(chǎn)生的表面等離子共振現(xiàn)象加速了光生電子的產(chǎn)生[29,39]。Lin等[27]通過調(diào)整Ag@Cu2O核殼異質(zhì)結(jié)中Cu2O殼的厚度可以使催化劑的光吸收范圍擴(kuò)展至整個可見光范圍或某一特定范圍。瞬態(tài)吸收光譜表明，等離子體引起的共振能量轉(zhuǎn)移和直接電子轉(zhuǎn)移兩種機(jī)制促成了從金屬到半導(dǎo)體的表面等離子體能量傳遞，從而導(dǎo)致Cu2O電荷分離。

金屬離子改性在一定程度上可改變Cu2O的能帶結(jié)構(gòu)進(jìn)而改變其光物理性能。光致發(fā)光光譜表明，摻雜Zn后的Cu2O能夠很容易被光照激發(fā)，產(chǎn)生大量載流子[31]。

2.1.1.2金屬離子改性量影響

金屬離子改性量會影響Cu2O的光催化活性。改性后Cu2O光催化劑表面的粗糙度、厚度、透光率都會影響光催化膜的活性[22]。另外，金屬離子改性后，會引入一定量的缺陷，這些缺陷可作為電子-空穴的復(fù)合中心，由此降低光催化性能。合適的Zn摻雜量被證實能夠明顯地提升光引發(fā)載流子的壽命[31]。Zhang等[29]發(fā)現(xiàn)復(fù)合物中Ag量過多時發(fā)生Ag顆粒團(tuán)聚，捕獲光電子的活性位點數(shù)目減少，Cu2O光催化活性降低。此外，復(fù)合物中金屬含量過多會阻礙Cu2O的可見光吸收，降低光子利用效率[29,40]。

2.1.1.3金屬離子改性形貌研究

金屬改性的Cu2O光催化劑的形貌不僅會因比表面積的改變而影響對目標(biāo)降解物的吸附，而且不同形貌立體空間的位置還會影響光催化劑光譜的吸收能力，圖2給出了不同形貌Cu2O光催化劑的SEM圖?；ǘ錉頒u2O/Cu納米復(fù)合物[32]和中空的Cu2O/Cu納米球[33]光催化活性均比納米顆粒和實心球狀的高，這是因為花朵狀和中空的Cu2O/Cu擁有大的比表面積，不僅提高了產(chǎn)物的吸附和解吸，而且吸光能力也得到增強(qiáng)。一維納米結(jié)構(gòu)如納米線、納米管、納米帶等具有各向異性并且能在最小尺度內(nèi)實現(xiàn)電子和激子的有效傳遞，因此在光催化材料制備中引起很大關(guān)注。Xiong等[23]研究發(fā)現(xiàn)，與核-殼Ag@Cu2O和Cu2O納米球相比，一維Ag@Cu2O納米線可見光下降解甲基橙(MO)活性更高，獨特的一維核-殼納米結(jié)構(gòu)在提高其光催化性能方面具有重要作用。

2.1.2非金屬改性

非金屬C,N,B,Si等改性的Cu2O光催化劑已經(jīng)得到廣泛研究，尤其C族改性的非常多，如活性炭[42]、碳納米管(CNTs)[43,44]、碳納米纖維(CNFs)[45,46]、石墨烯[47-51]。據(jù)已有報道，Cu2O與CNFs,CNTs復(fù)合后，其光催化活性都比純的Cu2O要好。與CNFs相比，CNTs比表面積更大，但是分散性較差且制備成本高。近期，石墨烯由于以下優(yōu)勢而逐漸受到重視：1)比表面積大(理論值達(dá)2600m2/g)[52]，提高催化劑表面吸附能力，此外，石墨烯作為良好的基底使Cu2O顆粒分散更均勻[53]；2)單原子厚度的石墨烯透光率高，利于照射光的吸收[48]；3)擁有二維π共軛結(jié)構(gòu)，石墨烯作為電子接收器有效分離電子-空穴[54]。CNTs和CNFs易團(tuán)聚，而石墨烯制備過程產(chǎn)生的缺陷和空位能夠降低導(dǎo)電性從而影響電子傳導(dǎo)，因此Zeng等[55]將不同C族物質(zhì)結(jié)合起來與Cu2O復(fù)合得到了更好的光催化效果，認(rèn)為在石墨烯/CNTs-Cu2O復(fù)合物中，CNTs作為1D的電子傳導(dǎo)通道，石墨烯作為巨大的2D電子傳導(dǎo)場地，建立了電荷高效分離網(wǎng)絡(luò)，由此極大地提高了光催化效果。

圖2　不同形貌Cu2O的SEM圖　(a)花朵狀Cu2O/Cu[32];(b)中空的Cu2O/Cu[33];(c)一維Ag@Cu2O納米線[23];(d)Ag@Cu2O納米球[29];(e)Cu2O納米球[41]Fig.2　SEM images of different morphologies Cu2O　(a)flowerlike Cu2O/Cu[32];(b)hollow Cu2O/Cu[33];(c)1D Ag@Cu2O nanowire[23];(d)Ag@Cu2O nanosphere[29];(e)Cu2O nanosphere[41]

此外，一些具有特殊性質(zhì)的高分子化合物越來越受到青睞，如聚苯胺、殼聚糖等。聚苯胺(PANI)具有特殊的電子-空穴傳遞特性，光照射PANI引發(fā)π-π*躍遷，光引發(fā)電子轉(zhuǎn)移至Cu2O導(dǎo)帶，而空穴則由Cu2O轉(zhuǎn)移至PANI的π軌道，從而使電荷有效分離[56,57]。殼聚糖(CS)對金屬離子有良好的配位絡(luò)合能力，能夠作為良好的基質(zhì)材料來定位及控制無機(jī)納米顆粒的生長。Cu2O/CS的特殊表面能夠增強(qiáng)催化劑對染料和氧分子的吸附，Cu2O包裹在交聯(lián)的CS內(nèi)，光引發(fā)電子被吸附的O2捕獲，提高其電子-空穴的分離效率[58,59]。

氮化硼(BN)、氮化碳(C3N4)與Cu2O復(fù)合也嶄露頭角，復(fù)合后催化活性均比純Cu2O高。Huang及其小組制備了Cu2O@h-BN(二維氮化硼)復(fù)合物，發(fā)現(xiàn)它能用于對硝基苯酚轉(zhuǎn)換成氨基苯酚的反應(yīng)，Cu2O@h-BN表現(xiàn)出很高的活性，h-BN本身不能完成此轉(zhuǎn)換，但是能吸附對硝基苯酚離子，利于反應(yīng)進(jìn)行[60]。瞬態(tài)光電流測量表明g-C3N4(類石墨氮化碳)質(zhì)量分?jǐn)?shù)為10%的Cu2O光電流分別是g-C3N4和Cu2O的4.2倍和14.4倍[61]。C3N4與Cu2O結(jié)合時，光引發(fā)電子由Cu2O轉(zhuǎn)移到C3N4，空穴則由C3N4轉(zhuǎn)移到Cu2O，使電子-空穴有效分離[61,62]。

2.2半導(dǎo)體復(fù)合改性

半導(dǎo)體復(fù)合是指復(fù)合兩種不同禁帶寬度的半導(dǎo)體，由于半導(dǎo)體的價帶、導(dǎo)帶和帶隙能不一致而發(fā)生交迭，從而提高光生電子和空穴的分離率，擴(kuò)展納米Cu2O的光譜響應(yīng)范圍；因此，與單一的半導(dǎo)體相比，復(fù)合半導(dǎo)體表現(xiàn)出更好的穩(wěn)定性和催化活性，克服了單一半導(dǎo)體催化劑量子效率低的缺點。

半導(dǎo)體復(fù)合常見的有兩種類型，即MxOy/Cu2O和MxSy/Cu2O(M代表半導(dǎo)體元素)。如TiO2/Cu2O[63-69],WO3/Cu2O[70-73],ZnO/Cu2O[74-76],Ru2O/Cu2O[77],BiVO4/Cu2O[78,79],SnO2/Cu2O[80],MoS2/Cu2O[81],CuxSy/Cu2O[41]等。

2.2.1與MxOy半導(dǎo)體復(fù)合

此外，半導(dǎo)體復(fù)合能夠提高光生電子-空穴的分離效率，從而使光催化性能提高。半導(dǎo)體復(fù)合中載流子的傳遞機(jī)制有兩種路徑，如圖3所示。一種機(jī)制是光照后，Cu2O與復(fù)合的半導(dǎo)體同時被激發(fā)產(chǎn)生電子(e-)-空穴(h+)對，Cu2O上的e-轉(zhuǎn)移至復(fù)合的半導(dǎo)體導(dǎo)帶，而h+則由復(fù)合的半導(dǎo)體轉(zhuǎn)移至Cu2O的價帶，如圖3(a)所示。另一種機(jī)制是光照后，只有Cu2O被激發(fā)產(chǎn)生電子(e-)-空穴(h+)對，Cu2O導(dǎo)帶e-轉(zhuǎn)移至復(fù)合的半導(dǎo)體上，如圖3(b)所示。

圖3　半導(dǎo)體復(fù)合中載流子的傳遞機(jī)制　(a)Cu2O與半導(dǎo)體同時激發(fā)產(chǎn)生電子-空穴對；(b)僅Cu2O激發(fā)產(chǎn)生電子-空穴對Fig.3　Transport mechanism of carriers in coupled semiconductors (a)e-/h+ are excited simultaneously from Cu2O and semiconductor; (b)e-/h+ are excited only from Cu2O

復(fù)合的半導(dǎo)體能夠作為電子捕獲劑[63,71]，有效抑制光生電子-空穴對的復(fù)合速率，從而提高Cu2O的光催化性能。同時，Cu2O與復(fù)合的半導(dǎo)體能帶結(jié)構(gòu)的匹配，可以使光引發(fā)電子由Cu2O導(dǎo)帶轉(zhuǎn)移到復(fù)合半導(dǎo)體的導(dǎo)帶，而空穴則由復(fù)合的半導(dǎo)體價帶轉(zhuǎn)移到Cu2O價帶[64,73,75,76,78,79]。此外，復(fù)合的半導(dǎo)體還可以作為助催化劑，降低反應(yīng)的活化能[77]。

2.2.2與MxSy半導(dǎo)體復(fù)合

Cu2O與MxSy型半導(dǎo)體復(fù)合研究的報道相對較少。MoS2具有類似于石墨的層狀結(jié)構(gòu)，在利用太陽能制備H2中，MoS2可以作為貴金屬(如Pt)的替代品助催化。Zhao等[81]采用MoS2修飾Cu2O得到MoS2@Cu2O，MoS2質(zhì)量分?jǐn)?shù)達(dá)到1.0%時光電流密度可達(dá)0.17mA/cm2，是純Cu2O的8倍，并且連續(xù)工作9h后催化劑僅損失7%，穩(wěn)定性得到很好的提升。納米MoS2能夠接受電子，可作為還原H+的活性位點，MoS2作為助催化劑能夠降低電化學(xué)質(zhì)子還原的超電勢，抑制光誘導(dǎo)的腐蝕。

2.3Cu2O穩(wěn)定性

盡管Cu2O顯示出優(yōu)異的光催化性能，但光腐蝕一直是Cu2O應(yīng)用所面臨的技術(shù)難題。Cu2O中的Cu+處于中間價態(tài)，很可能被空穴氧化為Cu2+或被電子還原為Cu?？蒲腥藛T進(jìn)行了大量Cu2O穩(wěn)定性方面的研究。Zheng等[83]發(fā)現(xiàn)在光催化降解甲基橙(MO)的過程中，Cu2O的{100}和{110}晶面逐漸消失，并且向{111}晶面轉(zhuǎn)化，而由{111}晶面為主導(dǎo)的Cu2O材料具有更好的穩(wěn)定性。Wu等[84]對Cu2O進(jìn)行重復(fù)循環(huán)極化和UV-Vis照射，發(fā)現(xiàn)Cu2O形貌由致密的三角形轉(zhuǎn)變?yōu)榉€(wěn)定的網(wǎng)狀拉長樹葉形，其XRD圖譜如圖4所示，始終以{111}晶面為主，因此認(rèn)為{111}最穩(wěn)定。

圖4　60次循環(huán)極化前后Cu2O的XRD圖譜[84]Fig.4　XRD patterns of Cu2O before and after 60 polarization cycles[84]

Paracchino等[85]采用原子層沉積法(Atomic Layer Deposition，ALD)在Cu2O上沉積超薄膜(Cu2O/Al:ZnO(20nm)/TiO2(10nm)/Pt)，組成為20nm厚Al摻雜ZnO，10nm厚TiO2，再沉積Pt納米顆粒，如圖5所示。盡管光照20min后光電流衰減，但是XPS測試證實Cu2O沒有發(fā)生光蝕，光電流衰減是因為TiO2膜中形成了Ti3+。保護(hù)層的高導(dǎo)電性能夠使Cu2O上的光電子轉(zhuǎn)移到電解質(zhì)中，降低Cu2O的自還原反應(yīng)。后來，Paracchino等[35]又對Cu2O/Al:ZnO(20nm)/TiO2(10nm)/Pt電極穩(wěn)定性進(jìn)行了研究，優(yōu)化沉積溫度、電解液pH值、TiO2退火溫度，通過合理選擇電解液并且盡可能使保護(hù)層晶化程度提高，經(jīng)10h的測試使穩(wěn)定性維持在62%以上。

圖5　Cu2O/Al:ZnO(20nm)/TiO2(10nm)/Pt[85]Fig.5　Cu2O/Al:ZnO(20nm)/TiO2(10nm)/Pt[85]

在Cu2O上覆蓋保護(hù)層成為改善其穩(wěn)定性的研究熱點[19,63,81]，但是覆蓋的保護(hù)層必須具備兩點：一是合適的帶隙，二是化學(xué)穩(wěn)定[35]。盡管Cu2O光催化穩(wěn)定性研究已取得一定的進(jìn)展，但效果還有待進(jìn)一步提高。

3　改性Cu2O研究展望

盡管改性后的Cu2O光催化性能得到一定程度的改善，但距離其實際應(yīng)用仍存在較大的差距，如圖6所示。

3.1制備方面

光催化活性與物質(zhì)的表面形貌關(guān)系密切[86]，而表面特性又與合理的制備方法不可分割，因此，為了獲得比表面積大、催化活性高、穩(wěn)定性好的光催化劑，不同的制備方法被應(yīng)用到Cu2O的制備，如水(溶劑)熱法、化學(xué)氣相沉積法、溶膠-凝膠法、電沉積法、磁控濺射法等。但制備過程中，做到晶體形貌可控、沉積的膜致密、與基底連接緊密、納米尺寸鍍膜卻很難。此外，選擇制備技術(shù)時還要兼顧費用、效果、大規(guī)模應(yīng)用等因素，因此，要達(dá)到以上效果的制備技術(shù)還需要進(jìn)一步研究。

3.2表征手段

目前，Cu2O光催化過程中載流子的動力學(xué)特性尚未清楚，嚴(yán)重阻礙了Cu2O光催化技術(shù)的發(fā)展，因此，運(yùn)用先進(jìn)的表征手段從微秒到秒的時間范圍內(nèi)來追蹤光引發(fā)空穴和電子的最終去向十分重要。瞬態(tài)吸收光譜(Transient Absorbance Spectra，TAS)、瞬態(tài)光電流(Transient Photo Current，TPC)等先進(jìn)技術(shù)的應(yīng)用將會極大地促進(jìn)Cu2O光催化技術(shù)的發(fā)展。

3.3二次污染問題

光催化降解廢水過程中，Cu2O納米顆粒遺落在水體環(huán)境中造成二次污染，影響水生生物。同時，改性Cu2O引入的陰陽離子也會對水中生態(tài)系統(tǒng)產(chǎn)生影響。例如，非金屬N的引入會造成水體的富營養(yǎng)化，S與細(xì)胞色素中的Fe反應(yīng)會抑制微生物呼吸。此外，金屬元素Pb,Zn,Cu等重金屬在水體中不可降解，不斷富集，甚至造成水生生物滅絕。為避免二次污染發(fā)生，除應(yīng)使Cu2O負(fù)載化以利于回收外，還應(yīng)加強(qiáng)制備技術(shù)的研究以增強(qiáng)材料在使用過程中的穩(wěn)定性。

圖6　改性Cu2O研究的發(fā)展趨勢Fig.6　Future trends of modified Cu2O

4　結(jié)束語

對Cu2O的改性研究是解決它在實際應(yīng)用中的限制的必要途徑，金屬/非金屬改性、半導(dǎo)體復(fù)合改性是目前主要的改性方法，并取得了一定的進(jìn)展，但光蝕和電子-空穴復(fù)合率高仍然是制約Cu2O光催化活性的主要問題。今后的研究一方面應(yīng)側(cè)重在改性機(jī)理方面加強(qiáng)對Cu2O光催化過程中載流子動力學(xué)研究，獲得能夠彌補(bǔ)Cu2O光催化過程中存在缺陷的改性材料；另一方面要完善Cu2O光催化性能評估體系，尋求更加合理的光催化性能評估方法和模型，使現(xiàn)有的單一指標(biāo)評價模式轉(zhuǎn)變?yōu)榫C合評價模式，更具實際意義。

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通訊作者：劉祥萱(1963-)，女，教授，博士，主要從事納米材料研究，聯(lián)系地址：陜西省西安市灞橋區(qū)同心路2號3603分隊(710025)，E-mail: wdwwdw1993@163.com

Progress in Research on Modified Cu2O Photocatalyst

GAO Xin1,LIU Xiang-xuan1,WANG Xuan-jun1,ZHU Zuo-ming2

(1 The Second Artillery Engineering University,Xi’an 710025,China;2 The Second Artillery Armament Institute,Beijing 100085,China)

The electronic and structural properties of Cu2O photocatalyst were outlined. Progress of metal/nonmetal ions modification and semiconductor coupled modification (includingMxOy/Cu2O andMxSy/Cu2O) was mainly discussed. Moreover, research status of the stability of Cu2O photocatalyst was analyzed. Future research of Cu2O modification was outlooked. The aspects of preparation technique, characterization and second pollution are considered to be started with, and study on modification mechanism and performance evaluation to be focused on.

Cu2O;photocatalysis;modification;stability

國家自然科學(xué)基金資助項目(51173079)；安徽省教學(xué)質(zhì)量工程項目(20101035,2013tszy034)

2014-11-06；

2015-11-25

張偉鋼(1982-)，男，博士，從事功能涂層材料方面研究，聯(lián)系地址：安徽省滁州市豐樂大道1528號滁州學(xué)院材料與化學(xué)工程學(xué)院(239000)，E-mail:abczwg15@163.com

10.11868/j.issn.1001-4381.2016.01.019

TB32

A

1001-4381(2016)01-0120-09

2014-12-08；2015-11-04