TiO2/pg-C3N4復(fù)合催化劑的制備及光催化性能

郭 梅,任學(xué)昌,王建釗,康 赟,孟 悅

TiO2/pg-C3N4復(fù)合催化劑的制備及光催化性能

郭 梅,任學(xué)昌*,王建釗,康 赟,孟 悅

(蘭州交通大學(xué)環(huán)境與市政工程學(xué)院,甘肅 蘭州 730070)

通過簡單的超聲剝離分散和水熱法,成功制得了具有多孔結(jié)構(gòu)的TiO2/pg-C3N4復(fù)合催化劑.利用XRD、SEM、TEM、UV-Vis DRS和PL對樣品的形貌、結(jié)構(gòu)及光學(xué)性能進(jìn)行了表征.在模擬太陽光照射下,以RhB和MO為模擬污染物考察了TiO2/pg-C3N4的光催化性能.結(jié)果表明:當(dāng)TiO2占pg-C3N4的質(zhì)量分?jǐn)?shù)為5% 時(shí),制得的TiO2/pg-C3N4(5:100)復(fù)合催化劑具有最優(yōu)的光催化性能.TiO2/pg-C3N4(5:100)對RhB的光催化降解途徑為O2·ˉ和h+使整個(gè)共軛發(fā)色團(tuán)結(jié)構(gòu)發(fā)生裂解.TiO2/pg-C3N4(5:100)光催化性能的提高一方面是由于多孔結(jié)構(gòu)增加了光催化反應(yīng)的活性位點(diǎn);另一方面是由于TiO2與pg-C3N4之間形成了Z型異質(zhì)結(jié),與傳統(tǒng)的Ⅱ型異質(zhì)結(jié)相比,該復(fù)合催化劑不僅使光生載流子分離效率提高,同時(shí)保留了pg-C3N4導(dǎo)帶電子的強(qiáng)還原性和TiO2價(jià)帶空穴的強(qiáng)氧化性.

石墨相氮化碳；TiO2/pg-C3N4；異質(zhì)結(jié)；多孔結(jié)構(gòu)；光催化

自2009年,Wang等[1]首次發(fā)現(xiàn)石墨相氮化碳(g-C3N4)能夠在可見光照射下催化分解水產(chǎn)生氫氣和氧氣以來,對g-C3N4光催化劑的研究成為眾多學(xué)者們關(guān)注的熱點(diǎn)[2-5].g-C3N4是一種典型的聚合物半導(dǎo)體[6],禁帶寬度約為2.7eV[7],具有穩(wěn)定性好、無毒環(huán)保、制備簡單和原料廉價(jià)的優(yōu)點(diǎn).然而純g-C3N4受自身比表面積小、光生載流子復(fù)合率高及光吸收范圍較窄(吸收帶邊約為460nm)的限制[6],太陽光利用率較低,其光催化性能并不理想.質(zhì)子化改性可以提高g-C3N4的比表面積、調(diào)節(jié)帶隙,同時(shí)借助質(zhì)子化氮化碳(pg-C3N4)還可以更容易的制備其他基于g-C3N4的復(fù)合材料[8].

二氧化鈦(TiO2)是最早受研究者們關(guān)注的半導(dǎo)體光催化劑之一[9],具有抗氧化能力強(qiáng)、化學(xué)性質(zhì)穩(wěn)定、價(jià)格低廉且無毒性[10]的優(yōu)點(diǎn),被認(rèn)為是最有希望投入應(yīng)用的光催化材料[11].然而,TiO2因光生載流子復(fù)合率較高[12]和只能吸收占太陽光4%左右的紫外光[10]而使其應(yīng)用受到限制.

近年來,利用g-C3N4與TiO2構(gòu)筑異質(zhì)結(jié),制備TiO2/g-C3N4復(fù)合催化劑已有相關(guān)的研究[10-15],然而對于pg-C3N4與TiO2復(fù)合的研究,目前尚未見相關(guān)報(bào)道.為使g-C3N4更容易剝離成較小的尺寸和形成多孔結(jié)構(gòu),本文對g-C3N4進(jìn)行質(zhì)子化;通過簡單的超聲剝離分散和水熱法將所獲得pg-C3N4與少量P25TiO2復(fù)合,成功制得了TiO2/pg-C3N4復(fù)合催化劑.TiO2/pg-C3N4具有多孔結(jié)構(gòu),增加了反應(yīng)的活性位點(diǎn);TiO2與pg-C3N4之間形成了Z型異質(zhì)結(jié),與傳統(tǒng)的Ⅱ型異質(zhì)結(jié)相比,該復(fù)合催化劑不僅使光生載流子分離效率提高,同時(shí)保留了pg-C3N4導(dǎo)帶電子的強(qiáng)還原性和TiO2價(jià)帶空穴的強(qiáng)氧化性.

1 材料與方法

1.1 試劑

尿素(天津光復(fù)科技發(fā)展有限公司)、P25TiO2(德國德固賽公司)、羅丹明B(鄭州市德眾化學(xué)試劑廠)、甲基橙(天津市天新精細(xì)化工開發(fā)中心)、對苯醌(天津市凱信化學(xué)工業(yè)有限公司);無水乙醇、異丙醇、乙二胺四乙酸二鈉均購自廣東光華科技股份有限公司,以上試劑均為分析純;鹽酸(洛陽昊華化學(xué)試劑有限公司)為優(yōu)級純.

1.2 儀器

SX2-4-10馬弗爐(上海實(shí)驗(yàn)電爐廠),FA2004分析天平(上海精密儀器儀表有限公司),KH5200超聲波清洗器(昆山禾創(chuàng)超聲儀器有限公司),TGL-16C離心機(jī)(上海安亭科學(xué)儀器廠),722G可見分光光度計(jì)(上海儀電分析儀器有限公司),UV-300紫外-可見分光光度計(jì)(賽默飛世爾科技有限公司),自制光催化反應(yīng)器.

1.3 催化劑的制備

1.3.1 g-C3N4的制備 取10g尿素研磨后置于坩堝中,用鋁箔紙封口,放入馬弗爐中升溫至550℃并保溫2h,自然冷卻至室溫,將所得淡黃色樣品研磨后即為g-C3N4[16].

1.3.2 pg-C3N4的制備 取1g制備好的g-C3N4樣品置于10mL濃HCl中,室溫下攪拌3h進(jìn)行質(zhì)子化,然后用去離子水和無水乙醇離心洗滌去除多余的HCl,105℃烘干12h,所得白色固體研磨后即為pg- C3N4[8].

1.3.3 多孔pg-C3N4的制備 取0.6g pg-C3N4樣品置于200mL乙醇-水溶液(乙醇:水=1:1)中,超聲震蕩2h[17],離心棄掉上清液,所得固體105℃烘干12h,研磨成粉末即為多孔pg-C3N4.

1.3.4 TiO2/pg-C3N4的制備 將0.5g pg-C3N4分別與0.005,0.025,0.05,0.1,0.2g TiO2混合后分散于100mL乙醇-水溶液(乙醇:水=1:1)中,超聲震蕩2h,轉(zhuǎn)入水熱反應(yīng)釜中,90℃反應(yīng)4h,離心棄掉上清液,所得固體105℃烘干12h,研磨成粉末即為1:100、5:100、10:100、20:100、40:100的TiO2/pg-C3N4復(fù)合催化劑.

1.4 催化劑表征

利用D/max-2400粉末X-射線衍射儀測試樣品的XRD譜圖,Cu靶,λ=0.154187nm;利用JSM- 6710F冷場發(fā)射掃描電鏡(FESEM)和TECNAI G2場發(fā)射透射電鏡(TEM)觀察樣品的形貌;利用Lambda 950紫外-可見光譜儀測試樣品的紫外-可見漫反射光譜(UV-Vis DRS),參比為BaSO4;利用F-7100熒光分光光度計(jì)測試樣品的熒光發(fā)射光譜(PL).

1.5 光催化反應(yīng)

采用自制的光催化反應(yīng)器[18],光源為500W氙燈,光催化反應(yīng)在玻璃反應(yīng)管(可過濾<300nm的紫外光)中進(jìn)行.以羅丹明B(RhB)、甲基橙(MO)作為模擬污染物進(jìn)行光催化實(shí)驗(yàn).準(zhǔn)確稱取0.3g催化劑于反應(yīng)管中,加入300mL濃度為10mg/L的模擬污染物溶液,黑暗條件下磁力攪拌40min使催化劑達(dá)到吸附平衡;然后開始光催化反應(yīng),每隔20min取一定量反應(yīng)液,12000r/min離心20min,并用0.22μm的有機(jī)針筒式過濾器過濾去除其中的少量催化劑,反應(yīng)時(shí)間共120min.然后用紫外-可見分光光度計(jì)全波長掃描檢測所得樣品的吸光度;或稀釋一定倍數(shù)后,用可見分光光度計(jì)在最大波長處測定樣品吸光度(RhB:554nm、MO:464nm).

2 結(jié)果與討論

2.1 催化劑表征分析

通過XRD譜圖分析催化劑的晶相組成,如圖1(a)所示.從TiO2的譜圖中可觀察到P25的典型衍射峰[11].g-C3N4和多孔pg-C3N4在13.2°和27.2°附近均出現(xiàn)了石墨相氮化碳的典型衍射峰,其中, 13.2°附近的弱峰,歸屬于g-C3N4的(100)晶面,對應(yīng)于g-C3N4內(nèi)部重復(fù)的三均三嗪結(jié)構(gòu)單元;27.2°附近的強(qiáng)峰歸屬于g-C3N4的(002)晶面,對應(yīng)于g-C3N4芳香環(huán)單元的層間堆疊[19].值得注意的是,多孔pg-C3N4在13.2°附近的峰強(qiáng)度變?nèi)?這是因?yàn)橘|(zhì)子化導(dǎo)致CN層的水平尺寸減小[17].TiO2/ pg-C3N4(5:100)中同時(shí)出現(xiàn)了多孔pg-C3N4和P25TiO2的衍射峰,說明pg-C3N4和P25TiO2成功復(fù)合到了一起.

對g-C3N4、多孔pg-C3N4、TiO2/pg-C3N4(5: 100)3種樣品在27.2°附近的峰進(jìn)行詳細(xì)分析,如圖1(b)所示.相對于g-C3N4,多孔pg-C3N4(002)晶面的出峰位置由27.2°移動(dòng)到27.62°,對應(yīng)的晶面間距則由0.328nm減小到0.323nm,表明質(zhì)子化使得石墨相氮化碳的層間距減小,與文獻(xiàn)[20]報(bào)道的相一致.對于TiO2/pg-C3N4(5:100),25.2°附近的峰對應(yīng)P25TiO2的(101)銳鈦礦衍射峰(晶面間距0.35nm)[11],pg-C3N4的(002)晶面衍射峰與P25TiO2的(110)金紅石衍射峰(晶面間距0.32nm)[11]發(fā)生重疊,出峰位置在27.3°.

通過SEM、TEM和高分辨率透射電鏡(HRTEM)分析催化劑的形貌、結(jié)構(gòu),如圖2所示.由圖2(a)、(c),多孔pg-C3N4是由納米級別和微米級別的片層堆疊而成,結(jié)構(gòu)蓬松,其表面和片層內(nèi)部均勻分布著大量的納米孔結(jié)構(gòu).由圖2(b)、(d)、(e),純P25TiO2為較規(guī)則的球形顆粒,但由于其平均粒徑很小,因而發(fā)生了比較嚴(yán)重的團(tuán)聚現(xiàn)象;TiO2/pg-C3N4(5:100)復(fù)合材料中,少量TiO2顆粒稀疏分散在pg-C3N4片層上,說明二者成功的復(fù)合到了一起,但TiO2顆粒仍有輕微的團(tuán)聚;TiO2/pg-C3N4(5:100)表面和片層內(nèi)部均勻的分布有大量的納米孔結(jié)構(gòu).圖2(f)HRTEM中,兩種晶格條紋分別是P25TiO2的銳鈦礦和金紅石的晶格條紋[21],對應(yīng)的(101)晶面間距和(110)晶面間距分別為0.35,0.32nm.由圖2可以看出,TiO2顆粒與pg-C3N4納米片緊密結(jié)合在一起,這與XRD分析結(jié)果相一致.

圖2 催化劑的SEM、TEM圖

SEM:(a)多孔pg-C3N4(b) TiO2/pg-C3N4(5:100) (TiO2插入b);TEM:(c)多孔pg-C3N4(d,e)TiO2/pg-C3N4(5:100) (TiO2插入d);HRTEM (f) TiO2/pg-C3N4(5:100)

圖3 催化劑的UV-Vis 吸收光譜和禁帶寬度(內(nèi)插)

通過UV-Vis DRS分析催化劑的紫外和可見光吸收性能,并利用Kubelka-Munk函數(shù)[()]1/2對作圖求得其禁帶寬度[11],如圖3所示.以尿素為前驅(qū)體制備的g-C3N4禁帶寬度為2.70eV,由E=1240/,其光吸收邊在459nm,與之前文獻(xiàn)[19]報(bào)道相一致.相對于g-C3N4,多孔pg-C3N4的光吸收發(fā)生了藍(lán)移,與文獻(xiàn)[8]中報(bào)道的相一致,其吸收邊藍(lán)移至438nm,禁帶寬度增大至2.83eV,這可能是由質(zhì)子化和超聲形成的多孔結(jié)構(gòu)及減小的尺寸引起的量子限域效應(yīng)造成的[17,22]. TiO2/pg-C3N4(5:100)復(fù)合材料的光吸收相對于多孔pg-C3N4僅有輕微的藍(lán)移,在一定程度上保存了pg-C3N4的光吸收性能;但其光吸收相對于TiO2則發(fā)生了明顯的紅移,吸收邊從406nm紅移至428nm,禁帶寬度從3.05eV減小至2.90eV.

通過PL分析催化劑的光生電子-空穴分離效率,如圖4所示,激發(fā)波長為300nm[11].g-C3N4的PL光譜發(fā)射峰在452nm,質(zhì)子化后多孔pg-C3N4的發(fā)射峰藍(lán)移至436nm,與文獻(xiàn)[8]報(bào)道的相一致,同時(shí)也與UV-Vis DRS顯示的光吸收藍(lán)移相一致;多孔pg-C3N4發(fā)射峰的強(qiáng)度相較于g-C3N4大幅度降低,表明其光生載流子的復(fù)合受到抑制. TiO2/pg-C3N4(5:100)的發(fā)射峰強(qiáng)度相較于pg-C3N4和TiO2均有所降低,其光生電子-空穴復(fù)合率非常低,表明pg-C3N4和TiO2之間形成了異質(zhì)結(jié),使得復(fù)合材料的光生電子和空穴的分離效率提高.

圖4 催化劑的PL光譜

2.2 光催化性能評價(jià)

催化劑降解RhB的光催化性能如圖5所示.直接光降解實(shí)驗(yàn)顯示RhB濃度沒有發(fā)生明顯的變化,說明在本實(shí)驗(yàn)條件下RhB相對穩(wěn)定.隨著TiO2/pg- C3N4復(fù)合催化劑中TiO2的比例增大,其對RhB的降解率呈先升高后降低的趨勢,其中TiO2/pg-C3N4(5:100)復(fù)合多孔催化劑表現(xiàn)出最優(yōu)的光催化活性,120min對RhB的降解率達(dá)到92.5%.其光催化活性的提高一方面是由于多孔結(jié)構(gòu)增加了光催化反應(yīng)的活性位點(diǎn);另一方面是由于TiO2與pg-C3N4之間形成了異質(zhì)結(jié),從而有效地提高了復(fù)合材料光生電子和空穴的分離效率,這與TEM、PL分析的結(jié)果是相一致的.

圖5 不同催化劑降解RhB的光催化活性

圖6 不同光催化反應(yīng)時(shí)間RhB溶液的紫外-可見吸收光譜圖

不同光催化反應(yīng)時(shí)間RhB溶液的紫外-可見吸收光譜如圖6所示.RhB溶液在554nm處的特征吸收峰隨著光催化反應(yīng)時(shí)間的延長而降低,同時(shí)樣品的最大吸收波長從554nm逐漸藍(lán)移至548nm,RhB的降解途徑為整個(gè)共軛發(fā)色團(tuán)結(jié)構(gòu)發(fā)生裂解[23],相對于脫乙基導(dǎo)致的藍(lán)移變化而言并不顯著(脫乙基通常藍(lán)移至498nm左右[23-24]).

為了進(jìn)一步證明TiO2/pg-C3N4(5:100)復(fù)合催化劑的光催化性能,又以MO為模擬污染物,測試了其光催化活性.如圖7所示,TiO2/pg-C3N4(5:100)同樣表現(xiàn)出良好的光催化性能,在模擬太陽光照射下,120min內(nèi)對MO的光催化降解率達(dá)到79.8%,是g-C3N4的7.96倍.

圖7 不同催化劑降解MO的光催化活性

2.3 光催化機(jī)理分析

TiO2/pg-C3N4(5:100)復(fù)合催化劑在模擬太陽光照射下光催化降解RhB的活性物種捕捉實(shí)驗(yàn)結(jié)果如圖8所示.以異丙醇(IPA)為·OH捕捉劑,對苯醌(BQ)為O2·ˉ捕捉劑,乙二胺四乙酸二鈉(EDTA-2Na)為h+捕捉劑[25].加入BQ(1mmol/L)和EDTA-2Na (1mmol/L)后RhB的降解受到明顯抑制,且BQ的影響大于EDTA-2Na,說明在TiO2/pg-C3N4(5:100)降解RhB過程中O2·ˉ和h+是主要活性物種,且O2·ˉ>h+.而加入IPA(0.1mL/L)后RhB的降解效果反而略有提高.有研究表明TiO2可以光催化氧化IPA水溶液[26], Yin等[27]也提出GO/電氣石/TiO2在氙燈照射下降解氣態(tài)IPA的主要活性物種為O2·ˉ和h+,其對IPA的降解包括3個(gè)過程:(1)半導(dǎo)體受激發(fā)產(chǎn)生電子和空穴,(2) O2+eˉ→ O2·ˉ, O2·ˉ氧化IPA;(3) h+直接氧化IPA.因此本文推測該體系內(nèi)加入IPA后RhB溶液中產(chǎn)生的O2·ˉ和h+的量增加,導(dǎo)致RhB降解效率提高.

圖8 活性物種捕捉實(shí)驗(yàn)

為分析TiO2/pg-C3N4(5:100)復(fù)合催化劑的光催化機(jī)理,通過以下半經(jīng)驗(yàn)公式[10,28]計(jì)算TiO2和pg- C3N4的價(jià)帶(VB)與導(dǎo)帶(CB)電勢.

式中:VB為半導(dǎo)體的價(jià)帶電勢,V;CB為半導(dǎo)體的導(dǎo)帶電勢,V;E為半導(dǎo)體的禁帶寬度,eV;為半導(dǎo)體的電負(fù)性,eV;E表示相對于氫標(biāo)的自由電子能,V;e為元電荷.

TiO2和pg-C3N4的值分別為5.81[10],4.82eV[29];E約4.5V[相對于氫標(biāo)準(zhǔn)電極(vs NHE)][10,28];由UV-ViS DRS分析可知TiO2和pg-C3N4的E分別為3.05,2.83eV.根據(jù)公式(1)、(2)計(jì)算可得,TiO2的VB和CB分別為2.84,-0.21V(vs NHE), pg-C3N4的VB和CB分別為1.73,﹣1.10V(vs NHE).pg-C3N4的CB比TiO2更負(fù),TiO2的VB比pg-C3N4更正.

如圖9所示,基于上述TiO2和pg-C3N4的能帶結(jié)構(gòu),TiO2/pg-C3N4(5:100)復(fù)合催化劑的光催化機(jī)理存在兩種可能性:(a)傳統(tǒng)II型異質(zhì)結(jié);(b)Z型異質(zhì)結(jié).在模擬太陽光照射下,TiO2和pg-C3N4受激發(fā)產(chǎn)生電子-空穴對,若遵循II型異質(zhì)結(jié)的機(jī)理,則pg-C3N4導(dǎo)帶中的光生電子將轉(zhuǎn)移到TiO2的導(dǎo)帶,同時(shí)TiO2價(jià)帶中的光生空穴將轉(zhuǎn)移到pg-C3N4的價(jià)帶.然而,由于O2/O2·ˉ的電位為-0.33V(vs NHE)[30],TiO2的CB(-0.21V)比0(O2/O2·ˉ)低,所以TiO2導(dǎo)帶中的電子不能與O2反應(yīng)生成O2·ˉ,這與活性物種捕捉實(shí)驗(yàn)的結(jié)果不一致.相反的,若遵循Z型異質(zhì)結(jié)的機(jī)理, TiO2導(dǎo)帶中的光生電子將轉(zhuǎn)移到pg-C3N4的價(jià)帶,并與pg-C3N4價(jià)帶中的光生空穴結(jié)合,導(dǎo)致pg-C3N4導(dǎo)帶中電子和TiO2價(jià)帶中空穴的累積.TiO2價(jià)帶中積累的空穴具有強(qiáng)氧化性,可直接降解RhB;而pg-C3N4的CB(-1.10V)比0(O2/O2·ˉ)更負(fù),其導(dǎo)帶中積累的電子可與O2反應(yīng)生成O2·ˉ.這與活性物種捕捉實(shí)驗(yàn)和PL光譜的結(jié)果相一致.綜上所述, TiO2/pg-C3N4(5:100)復(fù)合催化劑形成了Z型異質(zhì)結(jié),降低了光生電子和空穴的復(fù)合率;同時(shí)保留了pg- C3N4導(dǎo)帶電子的強(qiáng)還原性和TiO2價(jià)帶空穴的強(qiáng)氧化性.

(a) II 型異質(zhì)結(jié) (b) Z型異質(zhì)結(jié)

模擬太陽光照射下TiO2/pg-C3N4(5:100)復(fù)合催化劑降解RhB的主要反映過程如下:

TiO2/pg-C3N4+→TiO2/pg-C3N4(eˉ+ h+) (3)

TiO2/pg-C3N4(eˉ+h+)→pg-C3N4(eˉ)+TiO2(h+) (4)

O2+ eˉ→O2·ˉ (5)

O2·ˉ、h++ RhB→降解產(chǎn)物 (6)

3 結(jié)論

3.1 當(dāng)TiO2占pg-C3N4的質(zhì)量分?jǐn)?shù)為5% 時(shí),制得的TiO2/pg-C3N4(5:100)復(fù)合催化劑具有最優(yōu)的光催化性能,在模擬太陽光照射下,120min內(nèi)對RhB的降解率達(dá)到92.5%.

3.2 TiO2/pg-C3N4(5:100)對RhB的光催化降解途徑為O2·ˉ和h+使整個(gè)共軛發(fā)色團(tuán)結(jié)構(gòu)發(fā)生裂解.

3.3 TiO2/pg-C3N4(5:100)光催化性能的提高一方面是由于多孔結(jié)構(gòu)增加了光催化反應(yīng)的活性位點(diǎn);另一方面是由于TiO2與pg-C3N4之間形成了Z型異質(zhì)結(jié),與傳統(tǒng)的II型異質(zhì)結(jié)相比,該復(fù)合催化劑不僅使光生載流子分離效率提高,同時(shí)保留了pg-C3N4導(dǎo)帶電子的強(qiáng)還原性和TiO2價(jià)帶空穴的強(qiáng)氧化性.

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Preparation and photocatalytic properties of TiO2/pg-C3N4composite photocatalyst.

GUO Mei, REN Xue-chang*, WANG Jian-zhao, KANG Yun, MENG Yue

(School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China)., 2019,39(12)：5119~5125

The porous TiO2/pg-C3N4composite photocatalyst was successfully prepared by combining ultrasonic with hydrothermal treatment. XRD, SEM, TEM, UV-Vis DRS and PL were applied to analyze its morphology, structure and optical properties. The photocatalytic activities of the as-prepared samples were evaluated by degradating the simulated pollutants (RhB, MO) in aqueous solution under simulated sunlighti llumination. The result showed that the TiO2/pg-C3N4(5:100) exhibited the best photocatalytic degradation performance among all photocatalists with different compositions. The photocatalytic degradation pathway of RhB was chromophore cleavage caused by O2ˉ and h+. The improved photocatalytic performance of TiO2/pg-C3N4(5:100) was attributed to the fact that the active sites of the photocatalytic reaction were increased due to the porous structure, on the one hand, and a Z-scheme type heterojunction was formed between TiO2and pg-C3N4on the other hand, which not only can increase the separation efficiency of electron-hole pairs, but also can retain the stronger reducibility of photo-generated electrons on the more negative CB of pg-C3N4and higher oxidationability of photo-generated holes on the more positive VB of TiO2, compared with the conventional type II heterojunction.

graphitic carbon nitride；TiO2/pg-C3N4；heterojunction；porous structure；photocatalysis

X703.5

A

1000-6923(2019)12-5119-07

郭 梅(1990-),女,甘肅蘭州人,蘭州交通大學(xué)碩士研究生,主要從事水處理高級氧化技術(shù)研究.

2019-05-05

國家自然科學(xué)基金資助項(xiàng)目(51268026,51068016)

* 責(zé)任作者, 教授, rxchang1698@hotmail.com