201016596 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種氧化鋅奈米粒子的製法及一種新型的 氧化鋅奈米粒子。 【先前技術】 氧化鋅粉末係有利於作爲橡膠的加硫促進劑、塗料用顏 料、醫藥品、化妝品及合成樹脂等的添加劑、或作爲加入纖 維中的混練顔料等。又，其單體除了可作爲觸媒使用，更是 少數具有半導體性、光導電性或壓電性且於可見光範圍下本 質爲透明的物質，故亦爲壓電體材料、具有半導體性或壓電 性的光電材料，更可作爲電子照相用感光劑或鐵氧體 (ferrite)、可變電阻、螢光體等的電子零件材料等，係廣泛地 使用於各種領域中。 氧化鋅係代表性之η型氧化物半導體，因爲其優良的半 導體特性或壓電性及螢光發光特性等，故成爲重要之電子陶 瓷材料。再者，近年來如光觸媒、各種顯示裝置用的透明導 — 電性薄膜、螢光體、色素增感型太陽能電池用電極材料抑或 P型氧化物半導體等，其多樣化之應用備受注目。因此，正 在研發直徑未滿約10 〇nm的氧化鋅微粒子之製法。 已知有於氣相、液相中實施的氧化鋅製法。 (1)已知於工業上所使用對鋅蒸氣進行氣相氧化的乾式 法（俗稱美國式或法國式）或濕式法（德國式），係針對由鋅 或其化合物、含有羧基的化合物以及醇所組成的混合物進行 加熱的方法（例如參照專利文獻1 )。 201016596 (2)亦提出有一種使用高純度鋅作爲起始材料，並於酸 溶液中溶解該高純度鋅，而於溶解後之鋅溶液中加入碳酸鈉 或碳酸氫鈉以獲得碳酸鋅沈澱物，再對該沈澱物進行脫水、 乾燥而燒結的方法（例如參照專利文獻2 )。 但是，爲了獲得具有能配合該多樣化目的之特性的金屬 氧化物粉末，其形態之控制或尺寸的控制係爲重要問題，近 年來對於奈米級尺寸粒子徑的金屬氧化物粉末需求提高。另 一方面，依前述習知的製造方法，欲簡便且穩定地製造出奈 Φ米級尺寸且具有均勻粒徑分布的金屬氧化物粉末係至爲困難 的，對於奈米粒子之製法仍係相當不足而尋求改善。因此， 更不斷地開發氧化鋅奈米粒子之製法，目前爲止的改善後之 氧化鋅奈米粒子之製法係已知如下述。 (1)於醋酸鋅2水合物之乙醇溶液內加入氫氧化鋰之乙 醇溶液並靜置於0°C下，藉此係可獲得平均粒徑3nm至10nm 的氧化鋅奈米粒子，又，有報告提及該平均粒徑係可藉由靜 置的時間來加以控制（例如參照非專利文獻1 )。 ❹ (2)係揭露一種對溶解於醇中之鋅化合物及鋁化合物進 行水解（hydrolysis)，藉以調製成以醇作爲分散媒的氫氧化鋅 及氫氧化鋁溶膠，並對該獲得之溶膠進行凝膠化的同時形 成，再對該形成後的凝膠形成物進行燒結而產生含有氧化鋁 之氧化鋅陶瓷（例如參照專利文獻3 )。 (3)係揭露一種製造出包含有能再次以奈米粒子狀分散 且平均粒径15nm以下之氧化鋅、水及醇的氧化鋅凝膠，並於 二氯甲烷及/或三氯甲烷、抑或依需求以含有表面改質物質的 水或水/乙二醇混合物的溶劑中使其再分散而製成氧化鋅溶 201016596 膠的方法。（例如參照專利文獻4 )。 再者，欲獲得電氣特性時，係形成縱橫比較高之棒狀者 爲佳，已知有如下述之各種製法。 (4) 在氧氣存在下，使用金屬鋅靶來進行脈衝雷射沉 積，而於基板上形成氧化鋅奈米柱的方法（參照非專利文獻 2) (5) 在六亞甲四胺存在下使硝酸鋅加水分解、抑或在氨 存在下使氯化鋅加水分解·氧化後的玻璃上藉由水熱合成來 ® 形成氧化鋅奈米柱的方法（參照非專利文獻3以及非專利文 獻4) (6) 對氯化鋅水溶液進行噴霧熱裂解而於基板上形成氧 化鋅奈米柱的方法（參照非專利文獻5 ) (7) 在氧存在下使鋅蒸氣產生後，一邊氧化一邊於基板 上形成氧化鋅奈米柱的方法（參照非專利文獻6) 專利文獻 專利文獻1:特開平7-232919號公報 φ 專利文獻2:特開2001-39713號公報 專利文獻3 :特開平8-26823號公報 專利文獻4:特表2002-537219號 非專利文獻 非專利文獻 1 : Journal of Physical Chemistry B，102， pp.5566-5572 ( 1998 ) 非專利文獻 2: Superlattices and Microstructure 43( 2008 ) 594-599 非專利文獻 3 : Transactions of Nonferrous Metals Society 201016596 of China 18 ( 2008) 1089-1093. 非專利文獻 4 : Materials Science and Engineering B 145 (2007) 57-66. 非專利文獻 5: Superlattices and Microstructures.42 (2007) 444-450. 非專利文獻 6 : Applied Surface Science 255 (2009) 3972-3976. 【發明內容】 ® 但是，前述方法中係具有下列問題。 (1)因不具有積極地攪拌等的操作步驟，使得用於反應 之鋅化合物未完全轉變成氧化鋅而會殘留有許多之未反應 物，故氧化鋅奈米粒子之回收率較低。又，雖可藉由靜置時 間來控制粒徑，但其係於水溶液中進行反應，要控制氧化鋅 之結晶成長速度係爲困難的，不但難以獲得具有1 OOnm以下 粒徑的氧化鋅奈米粒子，將其規模放大後，有效的管理係變 得困難。 Ο (2)經長時間於溶液中穩定獲得分散之氧化鋅奈米粒子 的溶膠係爲困難的，將其規模放大後，係難以維持再現性。 (3) —旦生成微細粒子，又使其再度分散等生產成本較 多，長期間地保存亦具有相當大的問題點。 再者（4) ~(7)方法係於基板上形成氧化鋅奈米柱的方 法，而採集奈米柱必須要從基板上將其剝下，故操作性較差。 (5)及（6)方法中，鋅鹽溶液濃度低故生産性較差，又因 進行加水分解，係使用酸或鹼基來進行加熱等，需要具耐蝕 201016596 性高的反應容器°(4)及（7)方法，則係需要高真空或高溫 加熱等特殊裝置等的問題點。 因此’本發明之目的係提供一種對環境負擔較低、非常 簡便且回收效率高、能以工業規模穩定地製造氧化鋅奈米粒 子的方法。 本發明者於不停埋首硏究後，找到於水介質中藉由使鋅 金屬電極之間產生放電，且能適用於前述目的之氧化鋅奈米 粒子的製法，故完成本發明。 Φ 換句話說，依本發明係提供下述內容。 〔1〕在水介質中使金屬鋅電極之間產生放電的氧化鋅奈 米粒子之製法。 〔2〕於[1]中所述製法，其中該金屬鋅電極之間產生脈 衝放電。 〔3〕於[2]中所述製法，其中該脈衝放電係交流脈衝放 電。 〔4〕於[1]中所述製法，其中該金屬鋅電極之間產生直 ❹流放電。 〔5〕於〔1〕至〔4〕任一項所述製法所獲得之氧化鋅奈 米粒子。 〔6〕於[5]中所述氧化鋅奈米粒子，其中長軸爲 10~1OOOnm 〇 〔7〕於[5]或[6]中所述氧化鋅奈米粒子，其中縱橫比係 2以上。 〔8〕於〔5〕至〔7〕任一項所述氧化鋅奈米粒子’其中 係於拉曼光譜內顯示出El (LO)的峰値。 201016596 [發明效果] 依本發明製造方法係能以低電壓等較低的能量來製造出 粒徑較爲一致的氧化鋅奈米粒子。 【實施方式】 本發明之氧化鋅的製造方法係於水介質中使金靥鋅電極 之間產生放電。 (氧化鋅奈米粒子之形態） 依後述本發明的方法，係可藉由改變放電條件來製出各種 β 形態之氧化綷。於實用之放電條件下，通常係可獲得粒徑（長 軸尺寸）爲10〜l〇〇〇nm、縱橫比爲2〜500範圍的氧化鋅奈米粒 子。此處，本發明中縱橫比係指長軸相對於短軸之比例。 本發明方法之脈衝放電條件下，係可獲得長軸尺寸較佳 爲10〜lOOnm、縱橫比較佳爲2~20之長軸相對較小的氧化鋅 奈米粒子。 本發明之製法亦可爲連續放電條件，特別是連續直流放 電條件下，可獲得氧化鋅奈米柱。此處，氧化鋅奈米柱之縱 橫比較大，但相較於線、纖維，該氧化鋅奈米粒子之縱橫比 仍較小，本說明書中係指縱橫比爲2~5 00範圍內的氧化鋅奈 米粒子。氧化鋅奈米柱之縱橫比爲5~5 0 0者較佳，爲5~300 之範圍內者更佳。 (放電條件） 電極之形態係可爲棒狀、針狀、板狀等任意形態。關於 兩極之尺寸大小，無論何者爲大抑或具有相異形狀皆可。 本發明係於水介質中產生氧化鋅奈米粒子。作爲該水介 201016596 質者係可列舉出：水、水與水溶性有機溶劑之混合物等。作 爲水溶性有機溶劑者係可列舉出：甲醇、乙醇、丙醇等的醇 類；乙二醇、丙二醇、1，4-丁二醇、1，2-丁二醇等的二醇類； 二伸乙甘醇、三縮四乙二醇、聚氧乙烯等的氧化烯二醇類 (oxyalkylene glycols);抑或前述該等的烷基醚類等等。就經 濟效益之觀點來看，該水介質中水之混合比例較高者爲佳， 水介質中水溶性有機溶劑之比例係爲5 0重量％以下者爲佳。 水介質之使用量並無特殊限制，兩電極只要是在水介質 ® 中即可。更佳地，係藉由產生電漿來使水介質飛散，依照生 成物之濃度只要不使水介質之擴散性消失之程度即可。 本發明所使用的水並無特殊限制，考量如混入不純物係 會限制其用途，灰分含量應爲lOOppm以下者，較佳地，係 使用lOppm以下之離子交換水。 產生放電的溫度並無特殊限制，通常係室溫至300 °C範 圍，室溫至100 °C範圍者較佳，30 °C至80。(：範圍內實施者更 佳。特別是使用了有機溶劑時，於過高的溫度會使其所使用 © 之溶劑的蒸氣壓上升’可能會因電漿而著火故並不推薦，而 於過低的溫度則會讓溶劑之黏性上升，係有損該生成物的擴 散性故亦不推薦。 本發明係藉由於水介質中使金屬鋅電極之間產生脈衝電 漿放電’以形成長軸較小的氧化鋅奈米粒子。產生電漿的電 壓並無特殊限制，可爲50V〜500V範圍，考量安全性及特殊 裝置的必要性，於60V〜400V範圍者較佳，於80V-300V範 圍者更佳。產生電漿的電流亦無特殊限制，可爲0.^2 0A範 圍’考量能源效率，於0.2〜10A範圍內實施者較佳。脈衝電 201016596 漿之供給間隔雖無特殊限制，但爲5〜100毫秒者較佳，: 毫秒之循環者更佳》每次脈衝電漿的持續時間係因供 壓及電流而有所不同，但通常爲1〜50微秒，考量放電 爲2〜30微秒之範圍內實施者更佳。 本發明係藉由於水介質中使金屬鋅電極之間產生 電’以形成長軸與短軸皆較直流放電更小的氧化鋅奈 子。放電電壓並無特殊限制，通常爲5 0 V〜3 OOV範圍 安全性及特殊裝置的必要性，於60V〜220V範圍者較^ ® 8 0V~200V範圍者更佳。放電電流亦無特殊特殊限制， 化鋅奈米粒子之生成董係與電流量成比例關係，通常 0.1〜20A範圍，再考量能源效率，於l~l〇A範圍內實 佳。交流放電之頻率如使用50、6 0Hz中任一者皆無女 本發明係藉由於水介質中使金屬鋅電極之間產生 電，以形成氧化鋅奈米柱。放電電壓並無特殊限制， 50V〜3 00V範圍，考量安全性及特殊裝置的必要性，J 60V〜2 5 0V範圍者較佳，80V〜200V範圍者更佳。放電 ® 無特殊特殊限制，但因氧化鋅奈米粒子之生成量係與 成比例關係，通常爲0.1〜2 00A範圍，再考量能源效率， 範圍內實施者較佳。直流放電係可連續地進行，亦可 地進行。如進行間歇性放電之脈衝放電時，其放電間 特別限制，但就避免因熱量累積於電極而使鋅金屬熔 點來看，通常爲5~500毫秒之循環者較佳，爲6~100 循環者更佳。每次直流脈衝放電之持續時間係因供給 及電流而有所不同，但通常爲1微秒〜100毫秒範圍， 放電效率，爲2微秒~5 0毫秒範圍內實施者較佳。 6〜50 給之電 效率， 交流放 米粒 ，考量 圭，於 但因氧 爲 施者較 5。 直流放 通常爲 電流亦 電流量 1-100A 間歇性 隔雖無 化的觀 毫秒之 之電壓 再考量 -10- 201016596 本發明中放電時的電極間隔亦因供給之電壓及電流而有 所不同’但通常爲ΙΟ/zm至l〇mm之間，10以m至800以m 內實施者較佳。當電極間隔較前述範圍更近時，會因電流密 度過高，使熱量蓄積於電極的傾向產生而使鋅金屬熔化故並 不推薦，另一方面，當電極間隔較前述範圍更遠時，則會因 電流密度過低，而無法確保該反應開始所必須的能量故亦不 推薦。 本發明亦可對該電極施加振動。藉由施加振動係能使得 Φ解析出的氧化鋅奈米粒子不會滯留於該電極之間，能更有效 率地進行放電故爲較佳。施加振動的方法並無特殊限制，可 施加定期性振動，亦可施加間歇性振動的方法。例如，作爲 施加振動的手段係可使用氣動式振動器或電動式振動器等振 動器’但如使用電動致動器（actuator)則能穩定該振動的振幅 及該電極之間的距離，故爲更佳者。 雖然本發明係可於減壓、加壓、及常壓中任一狀態下實 施’但通常考量安全及操作性，於氮氣、氬氣等非活性氣體 φ 下實施者較佳。 (其他製造條件） 依本發明製造方法所形成的氧化鋅奈米粒子係分散浮游 於水中，故可藉由一般的方法，例如，藉由過濾、離心分離 等操作來捕集該浮游物’並進行乾燥以獲得氧化鋅奈米粒子。 實施例 以下，係列舉實施例來具體地說明本發明，但本發明並 未限定於此。 實施例1 -11- 201016596 於容量300ml的燒杯內坪入200g的水，將直徑5mm、 長100mm的金屬鋅電極（純度99%以上）插入該水中，而電 極之間隙係固定爲1mm，並使用電動致動器來施加振動。將 各電極連接至交流電源，並以200V、3A來進行脈衝電漿放 電。脈衝間隔爲20毫秒且每次放電的持續時間爲10微秒。 在放電開始的同時係可觀察到有黒色氧化鋅析出。連續進行 5小時放電後，取出電極並將具有浮游氧化鋅的反應液置於 離心分離機，以4000rPm進行30分鐘的離心分離，使目標物 ® 沉降。收集該沉降後的氧化鋅，以離子交換水2 0 0ml洗淨後 再用110 °C的熱風使其乾燥，而獲得3.5g氧化鋅奈米粒子。 進行和前述相同的操作而連續進行5小時放電後，藉由 傾析法將因離心分離而沉降的黒色氧化鋅粒子自反應液中分 離’再移放於設置有氣體收集器的玻璃製容器內。將該玻璃 製容器加熱至30 °C，並藉由氣體收集器來收集從黒色固體所 產生的氣體。加熱32小時後，黒色固體係呈白色化，而氣體 收集器係收集了 957ml的氣體。再以氣密注射器將該收集到 〇 的氣體取出，並藉由安裝有PDD檢測器（脈衝放電檢測器： Pulsed Discharge Detector)的氣相層析儀（島津製作所製 GC-14A )確認其係爲氫氣。相對於氧化鋅的生成量，已知係 保持有幾乎1: 1 (莫耳數比）的氫氣量。 對獲得之氧化鋅奈米粒子進行X光結晶分析（XRD Cu Κα; radiation，RigakuRINT-2500VHF)的結果係如第 1 圖所 示。由第1圖可知，獲得之粒子係爲氧化鋅。又，獲得之氧 化鋅奈米粒子的穿透式電子顯微鏡（TEM Philips Tecnai F2 0 S - Twin )照片係如第2圖所示。 -12- 201016596 實施例2 於實施例1中，除了以電壓200V、2A進行脈衝放電之 外，與實施例1相同地進行實驗，獲得3.2g氧化鋅。獲得之 氧化鋅奈米粒子的X光結晶分析與第1圖大致相同。獲得之 氧化鋅奈米粒子的穿透式電子顯微鏡照片係如第3圖所示。 實施例1及實施例2中所獲得之氧化鋅奈米粒子的數據 係如下表所示。係利用縮放工具（Noran System 6 )自TEM 照片測量出粒徑（長軸尺寸）及縱橫比。201016596 VI. Description of the Invention: [Technical Field] The present invention relates to a method for preparing zinc oxide nanoparticles and a novel zinc oxide nanoparticle. [Prior Art] The zinc oxide powder is advantageous as a vulcanization accelerator for rubber, an additive for coatings, an additive for pharmaceuticals, cosmetics, and synthetic resins, or a kneading pigment for adding fibers. Moreover, the monomer can be used as a catalyst, and is a small amount of a substance having semiconductivity, photoconductivity, or piezoelectricity and being substantially transparent in the visible light range, and thus is also a piezoelectric material, having a semiconductor property or a pressure. The electrophotoelectric material can be widely used in various fields as an electrophotographic sensitizer, an electronic component material such as a ferrite, a variable resistor, or a phosphor. The zinc oxide-based n-type oxide semiconductor is an important electronic ceramic material because of its excellent semiconductor characteristics, piezoelectricity, and fluorescent light-emitting characteristics. In addition, in recent years, various applications such as photocatalysts, transparent conductive films for various display devices, phosphors, electrode materials for dye-sensitized solar cells, or P-type oxide semiconductors have attracted attention. Therefore, a method of producing zinc oxide fine particles having a diameter of less than about 10 〇 nm is being developed. A zinc oxide process which is carried out in a gas phase or a liquid phase is known. (1) A dry method (commonly known as American or French) or a wet method (German type) which is known in the industry for vapor phase oxidation of zinc vapor, and is directed to zinc or a compound thereof, a compound containing a carboxyl group, and A method of heating a mixture of alcohols (for example, refer to Patent Document 1). 201016596 (2) It is also proposed to use high-purity zinc as a starting material and dissolve the high-purity zinc in an acid solution, and add sodium carbonate or sodium hydrogencarbonate to the dissolved zinc solution to obtain a zinc carbonate precipitate. Further, the precipitate is dehydrated, dried, and sintered (for example, see Patent Document 2). However, in order to obtain a metal oxide powder having characteristics suitable for the purpose of diversification, the control of the form or the control of the size is an important problem, and the demand for metal oxide powder having a nanometer-sized particle diameter has been increasing in recent years. On the other hand, according to the above-described conventional production method, it is difficult to easily and stably produce a metal oxide powder having a uniform Φ meter size and a uniform particle size distribution, and it is still quite suitable for the production of nano particles. Insufficient and seek improvement. Therefore, the production method of zinc oxide nanoparticle has been continuously developed, and the improved method of producing zinc oxide nanoparticle has been known as follows. (1) adding a solution of lithium hydroxide in an ethanol solution of zinc acetate 2 hydrate and standing at 0 ° C, whereby zinc oxide nanoparticles having an average particle diameter of 3 nm to 10 nm can be obtained, and The report mentions that the average particle diameter can be controlled by the time of standing (for example, refer to Non-Patent Document 1). (2) discloses a method of hydrolyzing a zinc compound and an aluminum compound dissolved in an alcohol to prepare a zinc hydroxide and an aluminum hydroxide sol using an alcohol as a dispersing medium, and coagulating the obtained sol. At the same time as the gelation, the formed gel formation is sintered to produce a zinc oxide ceramic containing alumina (see, for example, Patent Document 3). (3) It is disclosed that a zinc oxide gel containing zinc oxide, water and an alcohol which can be dispersed again in the form of nanoparticles and having an average particle diameter of 15 nm or less is produced in methylene chloride and/or chloroform, or A method of preparing zinc oxide-soluble 201016596 gel by redispersing it in a solvent containing water or a water/glycol mixture containing a surface modifying substance as needed. (For example, refer to Patent Document 4). Further, in order to obtain electrical characteristics, it is preferable to form a rod having a relatively high aspect ratio, and various methods as described below are known. (4) A method of forming a zinc oxide nano column on a substrate by using a metal zinc target for pulsed laser deposition in the presence of oxygen (refer to Non-Patent Document 2) (5) In the presence of hexamethylenetetramine A method of forming a zinc oxide nano column by hydrothermal synthesis of zinc nitrate by hydrolyzing or oxidizing zinc chloride in the presence of ammonia (see Non-Patent Document 3 and Non-Patent Document 4) 6) A method of forming a zinc oxide nano column on a substrate by spray pyrolysis of an aqueous zinc chloride solution (see Non-Patent Document 5) (7) After generating zinc vapor in the presence of oxygen, it is formed on the substrate while oxidizing In the case of the zinc oxide nano-column (see Non-Patent Document No. 6), the patent document No. JP-A No. Hei. No. Hei. No. Hei. Patent Document 4: Non-Patent Document No. 2002-537219 Non-Patent Document 1: Journal of Physical Chemistry B, 102, pp. 5566-5572 (1998) Non-Patent Document 2: Superlattices and Microstructure 43 (2008) 594-599 Patent literature 3: Transactions of Nonferrous Metals Society 201016596 of China 18 (2008) 1089-1093. Non-Patent Document 4: Materials Science and Engineering B 145 (2007) 57-66. Non-Patent Document 5: Superlattices and Microstructures. 42 (2007) 444 -450. Non-Patent Document 6: Applied Surface Science 255 (2009) 3972-3976. SUMMARY OF THE INVENTION However, the above methods have the following problems. (1) Since the zinc compound used for the reaction is not completely converted into zinc oxide and a large amount of unreacted material remains due to the fact that the zinc compound for the reaction is not completely stirred, the recovery rate of the zinc oxide nanoparticle is low. Further, although the particle diameter can be controlled by the standing time, it is difficult to obtain a zinc oxide crystal having a particle diameter of 100 nm or less by controlling the growth rate of zinc oxide in the aqueous solution. After the particles are enlarged, the effective management system becomes difficult. Ο (2) It is difficult to obtain a sol-form of dispersed zinc oxide nanoparticles stably in a solution for a long period of time, and it is difficult to maintain reproducibility after enlarging the scale. (3) Since the production of fine particles is repeated, the production costs are relatively high, and storage over a long period of time has considerable problems. Furthermore, the method (4) ~ (7) is a method of forming a zinc oxide nano column on a substrate, and the column for collecting the nano column must be peeled off from the substrate, so that the operability is poor. In the methods (5) and (6), the concentration of the zinc salt solution is low, so that the productivity is poor, and the hydrolysis is carried out by using an acid or a base for heating, etc., and a reaction vessel having a high corrosion resistance of 201016596 is required (4) And the method (7) requires problems such as special equipment such as high vacuum or high temperature heating. Therefore, the object of the present invention is to provide a method which can produce zinc oxide nanoparticles stably on an industrial scale with a low environmental burden, is very simple, and has high recovery efficiency. The inventors of the present invention have found a method for producing zinc oxide nanoparticles which are capable of being used for the above purpose by causing discharge between zinc metal electrodes in an aqueous medium, and have completed the present invention. Φ In other words, the following is provided in accordance with the present invention. [1] A method for producing zinc oxide nanoparticles which cause discharge between metal zinc electrodes in an aqueous medium. [2] The method according to [1], wherein a pulse discharge is generated between the metal zinc electrodes. [3] The method according to [2], wherein the pulse discharge is an alternating current pulse. [4] The process according to [1], wherein a direct turbulent discharge is generated between the metal zinc electrodes. [5] The zinc oxide nanoparticles obtained by the process according to any one of [1] to [4]. [6] The zinc oxide nanoparticle according to [5], wherein the long axis is 10 to 100 Å [7], the zinc oxide nanoparticle described in [5] or [6], wherein the aspect ratio is 2 or more . [8] The zinc oxide nanoparticle according to any one of [5] to [7] wherein a peak of El (LO) is exhibited in a Raman spectrum. 201016596 [Effect of the Invention] According to the manufacturing method of the present invention, zinc oxide nanoparticles having a relatively uniform particle diameter can be produced with a low energy such as a low voltage. [Embodiment] The method for producing zinc oxide according to the present invention is to cause discharge between gold and zinc electrodes in an aqueous medium. (Form of Zinc Oxide Nanoparticles) According to the method of the present invention to be described later, various β forms of cerium oxide can be produced by changing the discharge conditions. Under practical discharge conditions, zinc oxide nanoparticles having a particle diameter (long axis dimension) of 10 to 1 Å and an aspect ratio of 2 to 500 are usually obtained. Here, the aspect ratio in the present invention means the ratio of the major axis to the minor axis. Under the pulse discharge condition of the method of the present invention, zinc oxide nanoparticles having a long axis size of preferably 10 to 100 nm and a longitudinal axis of preferably 2 to 20 are relatively small. The process of the present invention can also be a continuous discharge condition, particularly under continuous DC discharge conditions, to obtain a zinc oxide nano column. Here, the aspect ratio of the zinc oxide nano-pillar is relatively large, but the aspect ratio of the zinc oxide nano-particle is still small compared to the wire and the fiber. In the present specification, the aspect ratio is an oxidation in the range of 2 to 500. Zinc nanoparticles. The aspect ratio of the zinc oxide nano column is preferably from 5 to 500, and more preferably from 5 to 300. (Discharge Condition) The form of the electrode may be any form such as a rod shape, a needle shape, or a plate shape. Regarding the size of the two poles, it can be either large or have a different shape. The present invention produces zinc oxide nanoparticles in an aqueous medium. As the water system 201016596, a mixture of water, water and a water-soluble organic solvent may be mentioned. Examples of the water-soluble organic solvent include alcohols such as methanol, ethanol, and propanol; and glycols such as ethylene glycol, propylene glycol, 1,4-butanediol, and 1,2-butanediol; Ethylene oxide glycols such as ethylene glycol, triethylene glycol, polyoxyethylene, etc.; or alkyl ethers or the like as described above. From the viewpoint of economic efficiency, it is preferred that the mixing ratio of water in the aqueous medium is higher, and the ratio of the water-soluble organic solvent in the aqueous medium is preferably 50% by weight or less. The amount of the aqueous medium used is not particularly limited, and the two electrodes may be used in the aqueous medium ® . More preferably, the aqueous medium is scattered by the generation of plasma, and the concentration of the raw material may be such that the diffusibility of the aqueous medium does not disappear. The water to be used in the present invention is not particularly limited, and if it is mixed with an impurity, the use thereof is limited, and the ash content should be 100 ppm or less. Preferably, ion exchange water of 10 ppm or less is used. The temperature at which the discharge is generated is not particularly limited, and is usually room temperature to 300 ° C, and room temperature to 100 ° C is preferred, and 30 ° C to 80 °. (: The implementer is better in the range. In particular, when an organic solvent is used, the vapor pressure of the solvent used in the use of an excessively high temperature may increase due to the plasma, so it is not recommended. A low temperature causes the viscosity of the solvent to rise, which is not recommended for the diffusion of the product. The present invention is based on the fact that a pulsed plasma discharge is generated between the metal zinc electrodes in the aqueous medium to form a long axis. Smaller zinc oxide nanoparticles. The voltage for generating plasma is not particularly limited. It can be in the range of 50V~500V. It is necessary to consider the safety and special equipment. It is better in the range of 60V~400V, in the range of 80V-300V. The current for generating plasma is also not particularly limited, and may be in the range of 0.^2 0A' to consider energy efficiency, preferably in the range of 0.2 to 10 A. Pulsed power 201016596 There is no special limitation on the supply interval of the slurry. However, it is better for 5 to 100 milliseconds, and the cycle of milliseconds is better. The duration of each pulse of plasma varies with supply voltage and current, but is usually 1 to 50 microseconds, and the discharge is 2 Better implementation within ~30 microseconds The invention is based on the fact that the electric medium is made to generate electricity between the metal zinc electrodes to form a long-axis and a short-axis which are smaller than the direct current discharge. The discharge voltage is not particularly limited, and is usually 5 0 V~3 OOV. Range safety and the necessity of special devices are better in the range of 60V~220V than in the range of ® 80V~200V. There is no special restriction on the discharge current. The generation of zinc nanoparticles is proportional to the current. Relationship, usually in the range of 0.1~20A, and then consider energy efficiency, which is better in the range of l~l〇A. The frequency of AC discharge is 50% or 60Hz, and none of the inventions are due to the metal in the aqueous medium. Electricity is generated between the zinc electrodes to form a zinc oxide nano column. The discharge voltage is not particularly limited, and the range of 50V to 300V is considered. The safety and the necessity of special devices are considered. The range of J 60V~2 5 0V is better, 80V. The range of ~200V is better. Discharge® is not particularly limited, but the amount of formation of zinc oxide nanoparticles is proportional to the range of 0.1 to 200 A, and energy efficiency is considered. DC discharge system It can be carried out continuously or in the same way. For the pulse discharge of intermittent discharge, the discharge is particularly limited, but the circulation of zinc metal is usually avoided due to the accumulation of heat on the electrode, which is usually 5 to 500 milliseconds. Preferably, it is better for 6 to 100 cycles. The duration of each DC pulse discharge varies depending on the supply and current, but is usually in the range of 1 microsecond to 100 milliseconds, and the discharge efficiency is 2 microseconds to 5 The implementation is better in the range of 0 milliseconds. 6~50 gives the electric efficiency, the AC puts the grain, considers it, but the oxygen is the donor. 5. The DC current is usually the current and the current is 1-100A. The voltage of milliseconds is considered again. -10- 201016596 The electrode spacing during discharge in the present invention is also different depending on the voltage and current supplied. 'But usually ΙΟ/zm to l〇mm, 10 to m to It is better to implement 800 in m. When the electrode spacing is closer than the above range, it is not recommended because the current density is too high, and the tendency of heat to accumulate on the electrode to melt the zinc metal is not recommended. On the other hand, when the electrode spacing is further than the aforementioned range, It is not recommended because the current density is too low to ensure the energy necessary to start the reaction. The present invention can also apply vibration to the electrode. By applying the vibration system, the zinc oxide nanoparticles which are analyzed by Φ are not retained between the electrodes, and discharge can be performed more efficiently, which is preferable. The method of applying the vibration is not particularly limited, and a periodic vibration or a method of intermittent vibration can be applied. For example, as a means for applying vibration, a vibrator such as a pneumatic vibrator or an electric vibrator can be used. However, if an electric actuator is used, the amplitude of the vibration and the distance between the electrodes can be stabilized. Better. Although the present invention can be carried out under any conditions of decompression, pressurization, and normal pressure, it is generally considered to be safe and operative, and it is preferably carried out under an inert gas φ such as nitrogen or argon. (Other manufacturing conditions) The zinc oxide nanoparticle formed by the production method of the present invention is dispersed and floated in water, so that the float can be trapped by a general method, for example, by filtration, centrifugation, or the like. Drying is performed to obtain zinc oxide nanoparticle. EXAMPLES Hereinafter, the present invention will be specifically described by way of examples, but the invention is not limited thereto. Example 1 -11- 201016596 200 g of water was placed in a 300 ml beaker, and a metal zinc electrode (purity of 99% or more) having a diameter of 5 mm and a length of 100 mm was inserted into the water, and the gap of the electrode was fixed at 1 mm and used. An electric actuator is used to apply vibration. Connect each electrode to an AC power source and pulse plasma discharge at 200V, 3A. The pulse interval is 20 milliseconds and the duration of each discharge is 10 microseconds. The precipitation of ochre zinc oxide was observed at the same time as the discharge started. After 5 hours of continuous discharge, the electrode was taken out and the reaction liquid having the floating zinc oxide was placed in a centrifugal separator, and centrifuged at 4000 rPm for 30 minutes to cause the target substance to settle. The precipitated zinc oxide was collected, washed with 200 ml of ion-exchanged water, and dried with hot air at 110 ° C to obtain 3.5 g of zinc oxide nanoparticles. After performing the same operation as described above and continuously discharging for 5 hours, the ochre zinc oxide particles which have settled by centrifugation are separated from the reaction liquid by a decantation method and then transferred to a glass container provided with a gas collector. . The glass vessel was heated to 30 ° C and the gas generated from the ochre solid was collected by a gas collector. After heating for 32 hours, the ochre solid was white, while the gas collector collected 957 ml of gas. The gas collected in the sputum was taken out by an airtight syringe, and the gas chromatograph (GC-14A manufactured by Shimadzu Corporation) equipped with a PDD detector (Pulse Discharge Detector) was confirmed to be hydrogen. It is known that the amount of hydrogen gas is maintained at almost 1:1 (molar ratio) with respect to the amount of zinc oxide formed. The results of X-ray crystallographic analysis (XRD Cu Κα; radiation, Rigaku RINT-2500 VHF) of the obtained zinc oxide nanoparticles were as shown in Fig. 1. As can be seen from Fig. 1, the obtained particles are zinc oxide. Further, a TEM Philips Tecnai F2 0 S - Twin photograph of the obtained zinc oxide nanoparticles is shown in Fig. 2. -12-201016596 Example 2 In the same manner as in Example 1, except that pulse discharge was performed at voltages of 200 V and 2 A, 3.2 g of zinc oxide was obtained. The X-ray crystal analysis of the obtained zinc oxide nanoparticles was substantially the same as in Fig. 1. The transmission electron micrograph of the obtained zinc oxide nanoparticle is shown in Fig. 3. The data of the zinc oxide nanoparticles obtained in Example 1 and Example 2 are shown in the following table. The particle size (long axis dimension) and the aspect ratio were measured from the TEM photograph using a zoom tool (Noran System 6).
表1 實施例No. 粒徑（nm) 縱橫比 實施例1 30 4 實施例2 50 6 實施例3 於容量300ml的量杯內押入200g的水，將直徑5mm、 長100mm的金屬鋅電極（純度99%以上）插入該水中，電極 之間隙係固定爲30〇em，再將各電極連接至交流電源，並以 200V、8A進行連續放電。在放電開始的同時係可觀察到氧化 φ 鋅析出，連續進行5小時的直流放電後，分離已沉降的大顆 粒子，於離心分離機以4000rpm進行30分鐘的離心分離’使 目標物沉降。收集該沉降後的氧化鋅，以離子交換水200ml 洗淨後再用110 °C的熱風使其乾燥，而獲得2.5g氧化鋅奈米 粒子》 獲得之氧化鋅奈米粒子的X光結晶分析（XRD Cu Κ α radiation，Rigaku RINT-2500VHF)結果如第 4 圖所示。 又，獲得之氧化鋅奈米粒子的穿透式電子顯微鏡（TEM Philips Tecnai F20 S-Twin)照片如圖 5 所示。 -13- 201016596 進行和前述相同的操作再藉由傾析法將沉降於 機內的黒色氧化鋅粒子分離，並移放於設置有氣體 玻璃製容器內。將該玻璃製容器加熱至3 0 °C，並藉 集器來收集從黒色固體所產生的氣體。加熱32小時 固體係呈白色化，而氣體收集器係收集了 667ml的 氣密注射器將該收集到的氣體取出，並藉由安裝有 器（脈衝放電檢測器：Pulsed Discharge Detector) 析儀（島津製作所製 GC-14A)確認其係爲氫氣。 ® 化鋅的生成量，已知係保持有幾乎1:1(莫耳數比 量。 實施例4 於實施例3中，除了以電壓200V、2A進行50 的脈衝放電，且每次放電持續時間爲1〇〇微秒之外 例3相同地進行實驗，而獲得2.2g氧化鋅。 獲得之氧化鋅奈米粒子的X光結晶分析（XRD radiation，RigakuRINT-2500VHF)結果如第 6 圖所 ❹ 又，獲得之氧化鋅奈米粒子的穿透式電子顯微Table 1 Example No. Particle size (nm) Aspect ratio Example 1 30 4 Example 2 50 6 Example 3 200 g of water was placed in a measuring cup having a capacity of 300 ml, and a metal zinc electrode having a diameter of 5 mm and a length of 100 mm was obtained (purity 99). More than %) was inserted into the water, and the gap between the electrodes was fixed at 30 〇em, and then the electrodes were connected to an AC power source and continuously discharged at 200 V and 8 A. At the same time as the start of the discharge, oxidized φ zinc was observed, and after continuous DC discharge for 5 hours, the precipitated large particles were separated and centrifuged at 4000 rpm for 30 minutes in a centrifugal separator to settle the target. The precipitated zinc oxide was collected, washed with 200 ml of ion-exchanged water, and then dried with hot air of 110 ° C to obtain an X-ray crystal analysis of the obtained zinc oxide nanoparticles by 2.5 g of zinc oxide nanoparticles. The results of XRD Cu Κ α radiation, Rigaku RINT-2500 VHF) are shown in Fig. 4. Further, a photo of a TEM Philips Tecnai F20 S-Twin obtained as a zinc oxide nanoparticle is shown in Fig. 5. -13- 201016596 The same operation as described above was carried out, and the ochre zinc oxide particles deposited in the machine were separated by decantation and placed in a vessel provided with a gas glass. The glass vessel was heated to 30 ° C and a collector was used to collect the gas generated from the ochre solid. The solid was whitened after heating for 32 hours, and the gas collector collected 667 ml of a gas-tight syringe to take out the collected gas, and installed it with a device (Pulsed Discharge Detector) (Shimadzu Manufacturing Co., Ltd.) GC-14A) was confirmed to be hydrogen. The amount of zinc produced is known to be maintained at almost 1:1 (molar ratio. Example 4 is the same as in Example 3 except that a pulse discharge of 50 at a voltage of 200 V, 2 A is performed, and each discharge duration The experiment was carried out in the same manner as in Example 3 except for 1 μ microsecond, and 2.2 g of zinc oxide was obtained. The X-ray crystal analysis (XRD radiation, Rigaku RINT-2500 VHF) of the obtained zinc oxide nanoparticle was as shown in Fig. 6 , the obtained electron microscopy of zinc oxide nanoparticles
Philips Tecnai F20 S-Twin)照片如第 7 圖所示。 實施例3及實施例4中所獲得之氧化鋅奈米粒 係如下表所示。利用縮放工具（Noran System 6) i 片測量出粒徑（長軸尺寸）及縱橫比。 離心分離 收集器的 由氣體收 後，黒色 氣體。以 PDD檢測 的氣相層 相對於氧 )的氫氣 毫秒間隔 ，與實施 Cu Κ α 示。 鏡（ΤΕΜ 子的數據 自ΤΕΜ照 -14 - 201016596 表2 實施例No. 粒徑（nm) 縱橫比 實施例3 120 25 實施例4 100 20 〔氧化鋅的拉曼光譜分析〕 實施例1(交流脈衝放電）及實施例3 (直流連續放電） 中所獲得之氧化鋅奈米粒子於放出氫以前的狀態（黑色粒子） 之拉曼光譜（由日本分光社製NRS-3 100測量）各自顯示於第9 圖及第10圖。於放出氫前後該頻譜並無變化。 β 爲了進行比較，利用燒結法將氫氧化鋅衍生出氧化鋅以 調製成的氧化鋅之拉曼光譜係如第8圖所示。 比較第8圖至第1 0圖，可以了解實施例1及實施例3所 獲得之氧化鋅（第9圖及第10圖）在El (LO)中均具有在 530〜630cm·1範圍之間的峰値。根據拉曼光譜之分析結果， 基於利用放電之本發明的氧化鋅奈米粒子製法，已知可獲得 具有氫複合物的新型氧化鋅奈米粒子、以及使該等放出氫所 形成的新型氧化鋅奈米粒子。 φ [產業利用性] 依本發明製法係能以低電壓等較低的能量來製造出粒徑 較爲一致的氧化鋅奈米粒子。所獲得之氧化鋅奈米粒子可適 用於光電材料、電子照相用感光劑、鐵氧體、可變電阻、蛋 光體等電子零件材料，其它亦適用於電子陶瓷材料、光觸媒、 各種顯示裝置用的透明導電薄膜、蛋光體、色素增感型太陽 能電池用電極材料、p型氧化物半導體等等用途’在產業上 爲有用的。 【圖式簡單說明】 -15- 201016596 第1圖係實施例1所獲得之氧化鋅的X光結晶分析結果 圖。圖式中縱軸爲強度，橫軸則爲20。 第2圖係實施例1所獲得之氧化鋅的穿透式電子顯微鏡 照片。圖式中縮尺表示爲50nm。 第3圖係實施例2所獲得之氧化鋅的穿透式電子顯微鏡 照片。圖式中縮尺表示爲0.0475ym。 第4圖係實施例3所獲得之氧化鋅的X光結晶分析結果 圖（縱軸爲強度 '橫軸爲20)。 ® 第5圖係實施例3所獲得之氧化鋅的穿透式電子顯微鏡 照片。圖式中縮尺表示爲50nm。 第6圖係實施例4所獲得之氧化鋅的X光結晶分析結果 圖（縱軸爲強度、橫軸爲20 )。 第7圖係實施例4所獲得之氧化鋅的穿透式電子顯微鏡 照片。圖式中縮尺表示爲50nm。 第8圖係藉由氫氧化鋅燒製法來誘導氧化鋅以調製成的 氧化鋅之拉曼光譜圖。 ® 第9圖係實施例1所獲得之氧化鋅的拉曼光譜圖。其係 表示氧化鋅之頻譜，故於放出氫的前後該頻譜並無變化。 第10圖係實施例3所獲得之氧化鋅的拉曼光譜圖。其係 表示氧化鋅之頻譜，故於放出氫的前後該頻譜並無變化。 【主要元件符號說明】 無。 -16-The Philips Tecnai F20 S-Twin) photo is shown in Figure 7. The zinc oxide nanoparticles obtained in Example 3 and Example 4 are shown in the following table. The particle size (long axis dimension) and aspect ratio were measured using a zoom tool (Noran System 6). The centrifugal separation of the collector is followed by gas, ochre gas. The millisecond interval of the hydrogen phase of the gas phase layer detected by PDD with respect to oxygen is shown by the implementation of Cu Κ α . Mirror (data for ΤΕΜ子ΤΕΜ-14 - 201016596) Table 2 Example No. Particle size (nm) Aspect ratio Example 3 120 25 Example 4 100 20 [Raman spectroscopy of zinc oxide] Example 1 (AC The Raman spectrum (measured by NRS-3 100 manufactured by JASCO Corporation) of each of the zinc oxide nanoparticles obtained in the pulse discharge and the third embodiment (direct current continuous discharge) before hydrogen evolution is shown in Fig. 9 and Fig. 10. The spectrum does not change before and after hydrogen evolution. β For comparison, the Raman spectrum of zinc oxide prepared by deriving zinc oxide from zinc oxide by sintering is as shown in Fig. 8. Comparing Fig. 8 to Fig. 10, it can be understood that the zinc oxide obtained in Example 1 and Example 3 (Fig. 9 and Fig. 10) has a range of 530 to 630 cm·1 in El (LO). According to the analysis result of Raman spectroscopy, it is known that a novel zinc oxide nanoparticle having a hydrogen complex can be obtained based on the method for producing zinc oxide nanoparticle of the present invention by discharge, and the hydrogen is released. Novel zinc oxide nanoparticle φ [Industrial Applicability] According to the method of the present invention, zinc oxide nanoparticles having a relatively uniform particle diameter can be produced with a low energy such as a low voltage. The obtained zinc oxide nanoparticles can be applied to photovoltaic materials and electrons. Photographic materials such as photographic agents, ferrites, varistor, egg optics, etc., other suitable for electronic ceramic materials, photocatalysts, transparent conductive films for various display devices, egg optics, dye-sensitized solar cells The use of an electrode material, a p-type oxide semiconductor, or the like is industrially useful. [Simple description of the drawing] -15- 201016596 Fig. 1 is a graph showing the results of X-ray crystallizing analysis of zinc oxide obtained in Example 1. In the drawing, the vertical axis is the intensity, and the horizontal axis is 20. Fig. 2 is a transmission electron micrograph of zinc oxide obtained in Example 1. The scale is shown as 50 nm in the figure. Fig. 3 is a second embodiment A transmission electron micrograph of the obtained zinc oxide. The scale in the figure is expressed as 0.0475 μm. Fig. 4 is a graph showing the results of X-ray crystallography analysis of zinc oxide obtained in Example 3 (the vertical axis is the intensity 'horizontal axis' is 20 ). ® 5 is a transmission electron micrograph of zinc oxide obtained in Example 3. The scale in the figure is expressed as 50 nm. Fig. 6 is a graph showing the results of X-ray crystallography analysis of zinc oxide obtained in Example 4 (the vertical axis is The intensity and the horizontal axis are 20). Fig. 7 is a transmission electron micrograph of zinc oxide obtained in Example 4. The scale in the figure is expressed as 50 nm. Fig. 8 is induced by a zinc hydroxide firing method. The Raman spectrum of zinc oxide prepared by zinc oxide. Figure 9 is a Raman spectrum of zinc oxide obtained in Example 1. It is a spectrum of zinc oxide, so the spectrum is before and after hydrogen evolution. Fig. 10 is a Raman spectrum of zinc oxide obtained in Example 3. It represents the spectrum of zinc oxide, so there is no change in the spectrum before and after hydrogen evolution. [Main component symbol description] None. -16-