{"created":"2023-06-19T10:30:15.200946+00:00","id":10485,"links":{},"metadata":{"_buckets":{"deposit":"eb6d432d-8c12-437e-aefd-d75c30e5db4c"},"_deposit":{"created_by":18,"id":"10485","owners":[18],"pid":{"revision_id":0,"type":"depid","value":"10485"},"status":"published"},"_oai":{"id":"oai:muroran-it.repo.nii.ac.jp:00010485","sets":["41:227"]},"author_link":["58614"],"item_81_date_granted_17":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2021-09-27"}]},"item_81_degree_grantor_10":{"attribute_name":"学位授与機関","attribute_value_mlt":[{"subitem_degreegrantor":[{"subitem_degreegrantor_language":"ja","subitem_degreegrantor_name":"室蘭工業大学"},{"subitem_degreegrantor_language":"en","subitem_degreegrantor_name":"Muroran Institute of Technology"}],"subitem_degreegrantor_identifier":[{"subitem_degreegrantor_identifier_name":"10103","subitem_degreegrantor_identifier_scheme":"kakenhi"}]}]},"item_81_degree_name_11":{"attribute_name":"学位名","attribute_value_mlt":[{"subitem_degreename":"博士（工学）","subitem_degreename_language":"ja"}]},"item_81_description_25":{"attribute_name":"フォーマット","attribute_value_mlt":[{"subitem_description":"application/pdf","subitem_description_type":"Other"}]},"item_81_description_7":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"既存の排水処理方法では、有機汚染物質が分解されず、二次汚染になる問題がある。したがって、本研究では、有機染料の分解のために酸化亜鉛(ZnO)光触媒による酸化処理の研究を行った。しかし、ZnOのような光触媒は、励起された電子-正孔対の速い再結合により触媒活性が制限されることと、使用後の回収が困難であることから再利用が制限されるという欠点がある。このような欠点を補完するために、電子シンクの役割をするAuまたはAg粒子の担持と、磁性を持つFe3O4との複合化を行った。第2-3章では、超音波噴霧熱分解(ultrasonic spray pyrolysis; USP)法を用いてAg/ZnOとAu/ZnO粒子を生成した。生成粒子のXRD結果では、ZnOの結晶ピークとAg又はAuの結晶ピークが観察された。TEMとEDX画像から粒子全体に分散しているダークスポットがAgまたはAuナノ粒子に該当することを確認した。また、ローダミンB (Rhodamine B; RhB)を有機汚染物のモデル物質として用いた光分解実験の結果から、生成したAu/ZnOとAg/ZnO粒子が純粋なZnO粒子よりも高い光触媒活性を持つことが分かった。特に、原料溶液として硝酸亜鉛2.5 mass%と塩化金酸0.1 mass%や硝酸銀0.2 mass%を用いて生成したAu/ZnO及びAg/ZnO粒子は、純粋なZnO粒子と比べて反応速度定数がそれぞれ約4倍、8倍高かった。得られたAu/ZnOとAg/ZnO粒子のなかには、広く光触媒として用いられているTiO2粒子であるP25より高い光分解活性を表す粒子もあった。100 mLのRhB水溶液を使って粒子の最適な添加量を評価した結果、粒子を2 mgから10 mgまで添加することにより、触媒活性は比例して増加したが、より高い添加量では際立った向上はなかった。電子励起に重要な紫外線が粒子によって散乱されたためだと考えられる。また、生成された粒子は、光分解実験後に重力沈殿による回収が可能であり、光触媒活性の劣化が遅いことも観察された。第4章では、粒子をより簡単に回収するために、強磁性Fe3O4粒子とZnO粒子の複合化を試みた。最初に硝酸亜鉛と塩化鉄の混合溶液からUSP法によってシングルステップで生成した粒子では、目的生成物であるZnOとFe3O4の結晶ピークは観察されず、ZnFe2O4のピークのみ観察された。次に、共沈法で生成したFe3O4をクエン酸を用いて表面改質物質した後、USP法により生成したZnO粒子と複合化した場合、ZnOとFe3O4の結晶ピークと磁力による沈降分離の促進が観察された。しかし、複合化されていないZnO粒子と粒子の凝集も観察された。最後に、塩化鉄と硫酸鉄を原料として共沈法で生成したFe3O4粒子に、硝酸亜鉛と硝酸銀の混合溶液を用いて共沈法により複合化した粒子では、目的生成物であるZnO、Ag、Fe3O4の結晶ピークが観察された。光分解実験では、実質的なZnOの添加量が減少するため、ZnO/Fe3O4複合粒子の光分解特性は純粋なZnO粒子より悪かった。しかし、ZnO/Fe3O4/Ag複合粒子は、Fe3O4が含まれているにもかかわらず、純粋なZnO粒子よりも優れた光分解特性を発揮した。本研究では、実際の廃水による分解実験は実施してないが、生成した複合粒子の有機汚染物質の浄化可能性が確認された。第5章では、本論文の総括を行った。","subitem_description_language":"ja","subitem_description_type":"Abstract"},{"subitem_description":"With existing wastewater treatment methods, there is a problem that organic pollutants are not decomposed and become secondary pollution. Therefore, in this study, a photocatalytic oxidation treatment was conducted for the decomposition of organic dyes. However, photocatalysts such as ZnO have the disadvantages that their catalytic activity is limited by the rapid recombination of excited electron-hole pairs and that their reuse is limited due to the difficulty of recovery after use. Therefore, Au and Ag, which act as electron sinks, were supported on the ZnO particles, and the composite was performed with Fe3O4 having magnetic properties. In Chapters 2-3, Ag/ZnO and Au/ZnO particles were generated using the ultrasonic spray pyrolysis (USP) method. In the XRD results, a ZnO crystal peak and an Ag or Au crystal peak were observed. From the TEM and EDX images, it was confirmed that the dark spots dispersed throughout the particles correspond to Ag or Au nanoparticles. In addition, as a result of photolysis experiments using Rhodamine B (Rhodamine B; RhB) as a model material for organic pollutants, the synthesized Au/ZnO and Ag/ZnO particles showed higher photolysis activity than pure ZnO particles generated by the USP method. In particular, the Au/ZnO and Ag/ZnO particles generated by adding 0.1mass% of HAuCl4 or 0.2mass% of AgNO3 to the 2.5mass% of Zn(NO3)2 aqueous solution showed reaction rate constants about 4 and 8 times higher than that of the pure ZnO particles, respectively. Among Au/ZnO and Ag/ZnO particles, some particles exhibited higher photodegradation activity than P25, which is a TiO2 particle widely used as a photocatalyst. As a result of evaluating the optimal amount of particles added using 100 mL of RhB aqueous solution, the catalytic activity increased from 2 mg to 10 mg in proportion to the addition of particles, but there was no obvious improvement in catalytic activity with more additions. It was also observed that the generated particles can be recovered by gravitational precipitation after the photodecomposition experiment, and the deterioration of photocatalytic activity is slow. In Chapter 4, a composite of ferromagnetic Fe3O4 particles and ZnO particles was attempted to recover particles more easily. First, in the particles generated from a mixed solution of zinc nitrate and iron chloride in a single step by the USP method, the crystal peaks of the target products ZnO and Fe3O4 were not observed, but only the peak of ZnFe2O4 was observed. Next, when ZnO particles produced by the USP method were combined with Fe3O4 produced by the coprecipitation method using citric acid as a surface modifier, the crystal peaks of ZnO and Fe3O4 and the promotion of sedimentation separation by magnetic force were observed. However, uncomposted ZnO particles and agglomeration of particles were also observed. Finally, Fe3O4 particles produced by coprecipitation using iron chloride and iron sulfate as raw materials were compounded by coprecipitation using a mixture of zinc nitrate and silver nitrate, and crystal peaks of ZnO, Ag, Fe3O4 were observed. In the photolysis experiment, the photodecomposition properties of the ZnO/Fe3O4 composite particles were worse than those of pure ZnO particles because the amount of ZnO added was substantially reduced. However, the ZnO/Fe3O4/Ag composite particles exhibited better photodegradation properties than the pure ZnO particles, even though they contained Fe3O4. In Chapter 5, the conclusion of this study was scrutinized.","subitem_description_language":"en","subitem_description_type":"Abstract"}]},"item_81_dissertation_number_13":{"attribute_name":"学位授与番号","attribute_value_mlt":[{"subitem_dissertationnumber":"甲第483号"}]},"item_81_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.15118/00010424","subitem_identifier_reg_type":"JaLC"}]},"item_81_subject_9":{"attribute_name":"日本十進分類法","attribute_value_mlt":[{"subitem_subject":"436","subitem_subject_scheme":"NDC"}]},"item_81_text_12":{"attribute_name":"学位の種別","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"課程博士"}]},"item_81_text_14":{"attribute_name":"報告番号","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"甲第483号"}]},"item_81_text_15":{"attribute_name":"学位記番号","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"博甲第483号"}]},"item_81_text_16":{"attribute_name":"研究科・専攻","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"工学専攻"}]},"item_81_version_type_24":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"open access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_abf2"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorAffiliations":[{"affiliationNameIdentifiers":[],"affiliationNames":[{"affiliationName":""}]}],"creatorNames":[{"creatorName":"李, 永俊","creatorNameLang":"ja"},{"creatorName":"イ, ヨンシュン","creatorNameLang":"ja-Kana"}],"familyNames":[{},{}],"givenNames":[{},{}],"nameIdentifiers":[{}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2021-12-09"}],"displaytype":"detail","filename":"A483.pdf","filesize":[{"value":"3.3 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"A483","objectType":"fulltext","url":"https://muroran-it.repo.nii.ac.jp/record/10485/files/A483.pdf"},"version_id":"ddc7dfc1-0bf9-4e55-8a28-6434c3240b85"},{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2021-12-09"}],"displaytype":"detail","filename":"A483_summary.pdf","filesize":[{"value":"495.6 kB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"A483_summary","objectType":"abstract","url":"https://muroran-it.repo.nii.ac.jp/record/10485/files/A483_summary.pdf"},"version_id":"57307ee1-330d-4181-bea9-2540d8ce979e"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"doctoral thesis","resourceuri":"http://purl.org/coar/resource_type/c_db06"}]},"item_title":"Generation of metal-supported ZnO-based particles and evaluation of photocatalytic properties for organic dye treatment","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Generation of metal-supported ZnO-based particles and evaluation of photocatalytic properties for organic dye treatment","subitem_title_language":"en"},{"subitem_title":"金属粒子を担持した酸化亜鉛粒子の生成と有機染料分解機能の評価","subitem_title_language":"ja"}]},"item_type_id":"81","owner":"18","path":["227"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2021-12-09"},"publish_date":"2021-12-09","publish_status":"0","recid":"10485","relation_version_is_last":true,"title":["Generation of metal-supported ZnO-based particles and evaluation of photocatalytic properties for organic dye treatment"],"weko_creator_id":"18","weko_shared_id":-1},"updated":"2024-01-22T02:05:39.548248+00:00"}