著者らは、スパッタコーター機器の支援のためのXRDスペクトルとK. Bookshと彼の助けをSvilen Bobevに感謝します。

1の合成ツリー状のZnO / CdSSe等ナノ構造<ol><li> サファイア基板の前処理および金コーティング 注：金膜は、酸化亜鉛ナノワイヤの成長の触媒として作用します。 <ol><li>超音波処理を5分間で99.5％エタノールで清浄なサファイアスライド（a面、10×10×1mmの）金スパッタリング用基板を作製しました。 </li><li>スパッタコーター及び金ターゲットとサファイアスライド上に10-nmの（±2 nm）の金の-thick膜を堆積。 </li></ol></li><li>酸化亜鉛ナノワイヤの合成 注：均質なZnOと炭素亜鉛（ZnO / C）混合物中の超音波処理ステップ1.2.2結果。混合後、混合物は灰色に変わります。圧縮ステップ1.2.3には空気が混合物中に存在しないとZnOと炭素が緊密に接触していることが保証されます。 CVD後、酸化亜鉛ナノワイヤの白色フィルムを基板上に堆積されるべきである、側ボートに向かって下向き。 <ol><li> ZnOナノ粉末とACTIVの1グラムを混ぜますated炭素（50:50の質量分率）10ミリリットル99.5％のエタノール中、スパチュラでよくかき混ぜます。 </li><li> 30分間、20ºCの水浴中の混合物を超音波処理し、その後、80ºCで〜5時間、オーブンで乾燥します。 </li><li>アルミナボートでのZnO / Cの混合物を配置し、スパチュラでよく、それをコンパクト。 </li><li>金でコーティングされた側を下に向けて、アルミナボートの上に金コーティングサファイアスライドを置きます。水平管炉内の石英管の中央にアルミナボートを置きます。 </li><li>室温（RT）で40sccmの流量でArで1時間石英管をパージします。 80ºC/分の速度で室温から900ºCに温度が上昇し、アルゴン流量を一定に保ちます。 </li><li> 2時間900ºCの温度を保持します。ゴム栓のガス入口を除去することにより、両端に石英管を開き、空気が反応のために酸素を提供するために、チューブを入力してみましょう。 </li><li> RUで3時間、900ºCでの反応温度を保ちますBBERストッパーを除去しました。 10ºC/ minの速度で室温まで冷却します。 </li><li>ボートや炉の外にスライドしてください。 </li></ol></li><li> 酸化亜鉛ナノワイヤ上CdSSe等の枝の堆積 注：のCdSのアルミナボート/ SEが中心石英管に表示されていました。用意したZnOナノワイヤを上向きにし、ボートから10cm下流でした。この第二のCVD後、酸化亜鉛/ CdSSe等のナノ構造体である黄色/オレンジ色のフィルムは、スライド上に堆積されるべきです。 <ol><li> CDとのCdSe（CDS / SE）の粉末ウェル（50:50の質量分率）の0.5グラムを混合し、アルミナボートに混合物を配置します。よく混合物を圧縮。 </li><li> CdS / Se及び石英管中で先に調製したZnOナノワイヤサンプルのアルミナボートを置きます。 </li><li> 1時間室温で40sccmの流量でArでチューブをパージ。 80ºC/分の速度で820ºCに反応温度を上げます。 30分間820ºCの温度を保持します。 </li><li>で室温まで冷却10ºC/ minの速度。ボートや炉の外にスライドしてください。 </li></ol></li><li> 対照試料の合成：ZnO及びCdSSe等ナノワイヤ <ol><li>同じ実験条件の下でセクション1.2のように酸化亜鉛ナノワイヤを合成します。 </li><li> CDやCdSeの組成物の同じ量で、同じ実験条件下では、1.3節のようにCdSSe等のナノワイヤを合成し、その代わりに、ZnOの堆積スライドの基板としてクリーン、金コーティングサファイアスライドを持ちます。 </li></ol></li></ol> 2.形態学的および結晶学的特性評価<ol><li>クランプでSEMステージ上にサンプルをマウントし、SEM装置の真空チャンバ内の試料を配置します。 3キロボルトの電圧で12.0ミリメートルの作動距離と3,000Xと10,000倍11,12間の倍率で高解像度モードでのSEM像を取ります。 </li><li>同じ作動距離でX線検出器を使用して同じサンプルとEDSデータを取ります12.0ミリメートル。分析モードに楽器を設定し、20から40μA13の現在の結果、20 kVのに電圧を調整します。 </li><li>フィルタリングCuKα線（λ= 1.5418Å）11,12を用いたX線粉末回折計でXRDスペクトルを収集します。 </li></ol> 3. PL発光分光と時間分解PL寿命測定注：PLは、RTでのスペクトルおよび時間相関単一光子計数（TCSPC）測定は、増幅のTiを用いて行った：第二高調波発生（SHG）後のサファイア発振器、400 nmの波長を中心とする50フェムト秒パルスの列を生成し1.76 mWの14の出力パワーを持ちます。 <ol><li>レーザーおよび検出器へのサンプル顔アップを配置する試料ホルダーに試料を固定してください。サンプルに焦点を当てるレーザーを合わせます。ファイバ分光計を用いて900 nmの波長の500 nmでのサンプルのPL発光スペクトルを測定します。 </li><li> （AVA単一光子検出器を使用色ガラスフィルタおよび500-または650 nmの干渉バンドパスフィルタを用いて時間分解PL寿命を測定するlancheフォトダイオードや光電管）。 </li><li>挿入ZnOは、CdSSe等、やZnO / CdSSe等は、試料ホルダーにスライド。 650 nmのバンドパスフィルターを用いて500 nmのバンドパスフィルタおよびCdSSe等やZnO / CdSSe等サンプルと純粋な酸化亜鉛ナノワイヤを測定します。 </li><li>時間分解蛍光減衰寿命を測定するための時間相関単一光子計数器または高速オシロスコープを使用してください。 </li></ol>

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この記事のデータと数値はLiら 17によりナノテクノロジーの文献から引用されています。

酸化亜鉛ナノワイヤ（茎）の垂直方向の配置は、基板上にエピタキシャル成長に基づいています。 ZnOナノワイヤは、サファイア12のa面の周期と一致する&lt;0001&gt;方向に沿って優先的に成長します。したがって、型及び基板の品質は非常に重要です。基板上の金コーティングの異なる厚さは、20ナノメートルから5ナノメートルから、試験したZnOナノワイヤの成長に有意な差を示されて?...

ZnOは3.3 eVのバンドギャップ（BG）、高電子移動度、大きな励起子結合エネルギー1,2を特徴II-VI半導体です。これは、光デバイス、太陽電池、光触媒に存在し、将来のアプリケーションの過多と豊富な半導体材料です。しかし、ZnOは可視スペクトル範囲におけるその適用を制限する、透明です。したがって、このような狭ギャップ半導体3、染料分子4、及び感光性ポリマー5のように可視光を吸収する材料は、しばしば可視光吸収のZnOを感作するために使用されてきました。 CdS（BG 2.43 eV）でとのCdSe（BG 1.76 eVでは）一般的なII-VI狭ギャップ半導体であり、集中的に研究されてきました。 BG及び三元合金CdSSe等の格子定数は、VI成分6,7のモル比を変えることによって調整することができます。酸化亜鉛/ CdSSe等のナノコンポジットは、効率的なphotovをもたらすことが報告されていますoltaicエネルギー変換8,9。 CdSSe等の枝の改善された可視光吸収を持つ基板に向かって垂直に配向したZnOナノワイヤの効率的な電子輸送経路を組み合わせることで、幹や枝9,10との間の効率的な電子移動につながりました。したがって、我々は、垂直配向のZnOナノワイヤはCdSSe等の枝が飾られて新しいツリー状のZnO / CdSSe等のナノ構造を、合成しました。この複合材料は、新規な太陽エネルギー変換装置のためのビルディングブロックとして作用することができます。 このプロトコルは、ZnOナノワイヤーアレイは、以前に11公表されている手順に従い、ZnOとC粉末から一段階化学気相堆積（CVD）によって、サファイア基板上に成長させる方法を記載しています。 ZnOナノワイヤの成長に続いて、CVD法の第二段階は、ZnOナノワイヤのCdSSe等の分岐を成長するために使用されます。我々は、X線粉末回折（XRD）、走査型電子顕微鏡（SEM）を用い、そして結晶構造、形態、及びZnO / CdSSe等のnanotrees（のNT）の組成を測定するためにエネルギー分散型X線分析（EDS）。分岐とステムとの間の光学的特性及び電荷キャリア移動機構は、フォトルミネッセンス（PL）分光法および時間分解PL寿命測定により研究されてきました。

<table><tbody><tr><td>ZnO</td><td>Sigma Aldrich</td><td>1314-13-2</td><td></td></tr><tr><td>Activated Carbon</td><td>Alfa</td><td>231-153-3</td><td></td></tr><tr><td>CdSe</td><td>Sigma Aldrich</td><td>1306-24-7</td><td></td></tr><tr><td>CdS</td><td>Sigma Aldrich</td><td>1306-23-6</td><td></td></tr><tr><td>Sapphire</td><td>MTI</td><td>2SP</td><td>a-plane, 10 &amp;times; 10 &amp;times; 1 mm</td></tr><tr><td>Furnace</td><td>Lindberg Blue M</td><td>SSP</td><td></td></tr><tr><td>Scanning electron microscope</td><td>Hitachi</td><td>S5700</td><td>assembled with an Oxford Inca X-act detector</td></tr><tr><td>X-ray powder diffractometer</td><td>Rigaku</td><td>MiniFlex</td><td>filtered Cu K&amp;alpha; radiation (&amp;lambda;=1.5418&amp;nbsp;&amp;Aring;)</td></tr><tr><td>Amplified Ti:sapphire oscillator</td><td>Coherent Mantis</td><td>Coherent Legend-Elite</td><td></td></tr><tr><td>Single photon detection module</td><td>ID Quantique</td><td>ID-100</td><td></td></tr><tr><td>Sputter coater</td><td>Cressington</td><td>308</td><td>assembled with gold target</td></tr><tr><td>Fiber probe spectrometer</td><td>Photon Control</td><td>SPM-002</td><td></td></tr><tr><td>Colored Glass Filter</td><td>Thorlabs</td><td>FGB37-A - &amp;Oslash;25 mm BG40</td><td>AR Coated: 350 - 700&amp;nbsp;nm</td></tr><tr><td>Compressed argon gas</td><td>Keen</td><td>7440-37-1</td><td></td></tr></tbody></table>

synthesis of hierarchical zno/cdsse heterostructure nanotrees

二段階化学蒸着手順はここで、ツリー状の階層のZnO / CdSSe等ヘテロナノ構造を作製するために使用されます。構造は、垂直に透明なサフ​​ァイア基板上に整列されたZnOナノワイヤの成長CdSSe等のブランチで構成されています。形態は、走査型電子顕微鏡により測定しました。結晶構造は、X線粉末回折分析により決定しました。 ZnO系幹とCdSSe等の枝の両方が主にウルツ鉱型の結晶構造を有しています。 CdSSe等の分岐におけるSおよびSeのモル比は、エネルギー分散型X線分光法により測定しました。 CdSSe等の枝は強い可視光吸収につながります。フォトルミネッセンス（PL）分光法は、幹や枝は、タイプIIのヘテロ接合を形成することが示されました。個々のZnOからの発光と比較した場合、PL寿命測定は、木からの発光の寿命の低下を示した茎やCdSSe等の支店およびCdSSe等とZnO間の高速電荷転送を示しています。 verti的に整列されたZnOを基板に直接電子輸送経路を提供し、可視光による光励起後の効率的な電荷分離を可能にする茎。上記の特性の組み合わせは、ZnO / CdSSe等は、太陽電池、光触媒、および光電子デバイスへの応用のための有望な候補をnanotreesなります。

図1は、ZnO / CdSSe等のNTの成長メカニズムを示しています。手順は、非接触気固体（VS）成長に続いて、触媒気相 - 液相 - 固相（VLS）処理を含みました。最初のVLS工程では、ZnOとCは、金属亜鉛及び酸化炭素を生じ、Ar雰囲気中で反応させます。亜鉛は、その後、サファイア基板上に金の前駆体中に溶解します。 ZnOナノワイヤは、溶解Znおよび残留酸素から成...

Watch this Scientific Journal Video about Synthesis of Hierarchical ZnO/CdSSe Heterostructure Nanotrees at JoVE.com

Synthesis of Hierarchical ZnO/CdSSe Heterostructure Nanotrees

ここでは、CdSSe等の枝が垂直配向のZnOナノワイヤ上で成長させた新たなツリー状の階層のZnO / CdSSe等のナノ構造を作製し、特徴づけます。得nanotreesは太陽エネルギー変換、および他の光電子デバイスのための潜在的な材料です。

階層型のZnO / CdSSe等ヘテロNanotreesの合成

A two-step chemical vapor deposition procedure is here employed to prepare tree-like hierarchical ZnO/CdSSe hetero-nanostructures. The structures are ...

synthesis-of-hierarchical-znocdsse-heterostructure-nanotrees

Universidad San Sebastian

Research

JoVE Journal

Chemistry

10.0K ビュー.  University of Delaware. ここでは、CdSSe等の枝が垂直配向のZnOナノワイヤ上で成長させた新たなツリー状の階層のZnO / CdSSe等のナノ構造を作製し、特徴づけます。得nanotreesは太陽エネルギー変換、および他の光電子デバイスのための潜在的な材料です。 

ビデオ: Synthesis of Hierarchical ZnO/CdSSe Heterostructure Nanotrees

Harvesting Solar Energy by Means of Charge-Separating Nanocrystals and Their Solids

Conjoining different semiconductor materials in a single nano-composite provides synthetic means for the development of novel optoelectronic materials offering a superior control over the spatial distribution of charge carriers across material interfaces. As this study demonstrates, a combination of donor-acceptor nanocrystal (NC) domains in a single nanoparticle can lead to the realization of efficient photocatalytic1-5 materials, while a layered assembly of donor- and acceptor-like nanocrystals films gives rise to photovoltaic materials.
Initially the paper focuses on the synthesis of composite inorganic nanocrystals, comprising linearly stacked ZnSe, CdS, and Pt domains, which jointly promote photoinduced charge separation. These structures are used in aqueous solutions for the photocatalysis of water under solar radiation, resulting in the production of H2 gas. To enhance the photoinduced separation of charges, a nanorod morphology with a linear gradient originating from an intrinsic electric field is used5. The inter-domain energetics are then optimized to drive photogenerated electrons toward the Pt catalytic site while expelling the holes to the surface of ZnSe domains for sacrificial regeneration (via methanol). Here we show that the only efficient way to produce hydrogen is to use electron-donating ligands to passivate the surface states by tuning the energy level alignment at the semiconductor-ligand interface. Stable and efficient reduction of water is allowed by these ligands due to the fact that they fill vacancies in the valence band of the semiconductor domain, preventing energetic holes from degrading it. Specifically, we show that the energy of the hole is transferred to the ligand moiety, leaving the semiconductor domain functional. This enables us to return the entire nanocrystal-ligand system to a functional state, when the ligands are degraded, by simply adding fresh ligands to the system4.
To promote a photovoltaic charge separation, we use a composite two-layer solid of PbS and TiO2 films. In this configuration, photoinduced electrons are injected into TiO2 and are subsequently picked up by an FTO electrode, while holes are channeled to a Au electrode via PbS layer6. To develop the latter we introduce a Semiconductor Matrix Encapsulated Nanocrystal Arrays (SMENA) strategy, which allows bonding PbS NCs into the surrounding matrix of CdS semiconductor. As a result, fabricated solids exhibit excellent thermal stability, attributed to the heteroepitaxial structure of nanocrystal-matrix interfaces, and show compelling light-harvesting performance in prototype solar cells7.

A general strategy for the development of charge-separating semiconductor nanocrystal composites deployable for solar energy production is presented. We show that assembly of donor-acceptor nanocrystal domains in a single nanoparticle geometry gives rise to a photocatalytic function, while bulk-heterojunctions of donor-acceptor nanocrystal films can be used for photovoltaic energy conversion.

電荷分離ナノ結晶とその固体の手段によって太陽エネルギーを収穫

Conjoining different semiconductor materials in a single nano-composite provides synthetic means for the development of novel optoelectronic materials ...

工学

Seeded Synthesis of CdSe/CdS Rod and Tetrapod Nanocrystals

We demonstrate a method for the synthesis of multicomponent nanostructures consisting of CdS and CdSe with rod and tetrapod morphologies. A seeded synthesis strategy is used in which spherical seeds of CdSe are prepared first using a hot-injection technique. By controlling the crystal structure of the seed to be either wurtzite or zinc-blende, the subsequent hot-injection growth of CdS off of the seed results in either a rod-shaped or tetrapod-shaped nanocrystal, respectively. The phase and morphology of the synthesized nanocrystals are confirmed using X-ray diffraction and transmission electron microscopy, demonstrating that the nanocrystals are phase-pure and have a consistent morphology. The extinction coefficient and quantum yield of the synthesized nanocrystals are calculated using UV-Vis absorption spectroscopy and photoluminescence spectroscopy. The rods and tetrapods exhibit extinction coefficients and quantum yields that are higher than that of the bare seeds. This synthesis demonstrates the precise arrangement of materials that can be achieved at the nanoscale by using a seeded synthetic approach.

A protocol for the seeded synthesis of rod-shaped and tetrapod-shaped multicomponent nanostructures consisting of CdS and CdSe is presented.

のCdSe / CdSのロッドやテトラポッドナノ結晶のシードの合成

We demonstrate a method for the synthesis of multicomponent nanostructures consisting of CdS and CdSe with rod and tetrapod morphologies. A seeded ...

化学

Ultrahigh Density Array of Vertically Aligned Small-molecular Organic Nanowires on Arbitrary Substrates

In recent years &pi;-conjugated organic semiconductors have emerged as the active material in a number of diverse applications including large-area, low-cost displays, photovoltaics, printable and flexible electronics and organic spin valves. Organics allow (a) low-cost, low-temperature processing and (b) molecular-level design of electronic, optical and spin transport characteristics. Such features are not readily available for mainstream inorganic semiconductors, which have enabled organics to carve a niche in the silicon-dominated electronics market. The first generation of organic-based devices has focused on thin film geometries, grown by physical vapor deposition or solution processing. However, it has been realized that organic nanostructures can be used to enhance performance of above-mentioned applications and significant effort has been invested in exploring methods for organic nanostructure fabrication.	
A particularly interesting class of organic nanostructures is the one in which vertically oriented organic nanowires, nanorods or nanotubes are organized in a well-regimented, high-density array. Such structures are highly versatile and are ideal morphological architectures for various applications such as chemical sensors, split-dipole nanoantennas, photovoltaic devices with radially heterostructured "core-shell" nanowires, and memory devices with a cross-point geometry. Such architecture is generally realized by a template-directed approach. In the past this method has been used to grow metal and inorganic semiconductor nanowire arrays. More recently &pi;-conjugated polymer nanowires have been grown within nanoporous templates. However, these approaches have had limited success in growing nanowires of technologically important &pi;-conjugated small molecular weight organics, such as tris-8-hydroxyquinoline aluminum (Alq3), rubrene and methanofullerenes, which are commonly used in diverse areas including organic displays, photovoltaics, thin film transistors and spintronics.	
Recently we have been able to address the above-mentioned issue by employing a novel "centrifugation-assisted" approach. This method therefore broadens the spectrum of organic materials that can be patterned in a vertically ordered nanowire array. Due to the technological importance of Alq3, rubrene and methanofullerenes, our method can be used to explore how the nanostructuring of these materials affects the performance of aforementioned organic devices. The purpose of this article is to describe the technical details of the above-mentioned protocol, demonstrate how this process can be extended to grow small-molecular organic nanowires on arbitrary substrates and finally, to discuss the critical steps, limitations, possible modifications, trouble-shooting and future applications.

We report a simple method for fabricating an ultrahigh density array of vertically ordered small-molecular organic nanowires. This method allows for synthesis of complex heterostructured hybrid nanowire geometries, which can be inexpensively grown on arbitrary substrates. These structures have potential applications in organic electronics, optoelectronics, chemical sensing, photovoltaics and spintronics.

任意の基板上の垂直配向小分子有機ナノワイヤーの超高密度アレイ

In  recent years &pi;-conjugated  organic semiconductors have emerged as the active material in a number of  diverse applications including large-area, ...

Atomically Defined Templates for Epitaxial Growth of Complex Oxide Thin Films

Atomically defined substrate surfaces are prerequisite for the epitaxial growth of complex oxide thin films. In this protocol, two approaches to obtain such surfaces are described. The first approach is the preparation of single terminated perovskite SrTiO3 (001) and DyScO3 (110) substrates. Wet etching was used to selectively remove one of the two possible surface terminations, while an annealing step was used to increase the smoothness of the surface. The resulting single terminated surfaces allow for the heteroepitaxial growth of perovskite oxide thin films with high crystalline quality and well-defined interfaces between substrate and film. In the second approach, seed layers for epitaxial film growth on arbitrary substrates were created by Langmuir-Blodgett (LB) deposition of nanosheets. As model system Ca2Nb3O10- nanosheets were used, prepared by delamination of their layered parent compound HCa2Nb3O10. A key advantage of creating seed layers with nanosheets is that relatively expensive and size-limited single crystalline substrates can be replaced by virtually any substrate material.

Various procedures are outlined to prepare atomically defined templates for epitaxial growth of complex oxide thin films. Chemical treatments of single crystalline SrTiO3 (001) and DyScO3 (110) substrates were performed to obtain atomically smooth, single terminated surfaces. Ca2 Nb3 O10- nanosheets were used to create atomically defined templates on arbitrary substrates.

複合酸化物薄膜のエピタキシャル成長のために原子的に定義されたテンプレート

Atomically defined substrate surfaces are prerequisite for the epitaxial growth of complex oxide thin films. In this protocol, two approaches to obtain ...

Preparation of ZnO Nanorod/Graphene/ZnO Nanorod Epitaxial Double Heterostructure for Piezoelectrical Nanogenerator by Using Preheating Hydrothermal

Well-aligned ZnO nanostructures have been intensively studied over the last decade for remarkable physical properties and enormous applications. Here, we describe a one-step fabrication technique to synthesis freestanding ZnO nanorod/graphene/ZnO nanorod double heterostructure. The preparation of the double heterostructure is performed by using thermal chemical vapor deposition (CVD) and preheating hydrothermal technique. In addition, the morphological properties were characterized by using the scanning electron microscopy (SEM). The utility of freestanding double heterostructure is demonstrated by fabricating the piezoelectric nanogenerator. The electrical output is improved up to 200% compared to that of a single heterostructure owing to the coupling effect of the piezoelectricity between the arrays of ZnO nanorods on the top and bottom of graphene. This unique double heterostructure have a tremendous potential for applications of electrical and optoelectrical devices where the high number density and specific surface area of nanorod are needed, such as pressure sensor, immuno-biosensor and dye-sensitized solar cells.

One-step fabrication method for obtaining freestanding epitaxial double heterostructure is presented. This approach could achieve ZnO coverage with a higher number density than that of the epitaxial single heterostructure, leading to a piezoelectric nanogenerator with an increased output electrical performance.

予熱水熱を利用したピエゾ電気NanogeneratorためのZnOナノロッド/グラフェン/ ZnOのナノロッドエピタキシャルダブルヘテロ構造の作製

Well-aligned ZnO nanostructures have been intensively studied over the last decade for remarkable physical properties and enormous applications. Here, we ...

Well-aligned Vertically Oriented ZnO Nanorod Arrays and their Application in Inverted Small Molecule Solar Cells

This manuscript describes how to design and fabricate efficient inverted solar cells, which are based on a two-dimensional conjugated small molecule (SMPV1) and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), by utilizing ZnO nanorods (NRs) grown on a high quality Al-doped ZnO (AZO) seed layer. The inverted SMPV1:PC71BM solar cells with ZnO NRs that grew on both a sputtered and sol-gel processed AZO seed layer are fabricated. Compared with the AZO thin film prepared by the sol-gel method, the sputtered AZO thin film exhibits better crystallization and lower surface roughness, according to X-ray diffraction (XRD) and atomic force microscope (AFM) measurements. The orientation of the ZnO NRs grown on a sputtered AZO seed layer shows better vertical alignment, which is beneficial for the deposition of the subsequent active layer, forming better surface morphologies. Generally, the surface morphology of the active layer mainly dominates the fill factor (FF) of the devices. Consequently, the well-aligned ZnO NRs can be used to improve the carrier collection of the active layer and to increase the FF of the solar cells. Moreover, as an anti-reflection structure, it can also be utilized to enhance the light harvesting of the absorption layer, with the power conversion efficiency (PCE) of solar cells reaching 6.01%, higher than the sol-gel based solar cells with an efficiency of 4.74%.

This manuscript describes how to design and fabricate efficient inverted SMPV1:PC71BM solar cells with ZnO nanorods (NRs) grown on a high quality Al-doped ZnO (AZO) seed layer. The well-aligned vertically oriented ZnO NRs exhibit high crystalline properties. The power conversion efficiency of solar cells can reach 6.01%.

整列垂直方向に配向 ZnO ナノロッド配列と反転小さな分子の太陽電池の応用

This manuscript describes how to design and fabricate efficient inverted solar cells, which are based on a two-dimensional conjugated small molecule ...

A Standard and Reliable Method to Fabricate Two-Dimensional Nanoelectronics

Two-dimensional (2D) materials have attracted huge attention due to their unique properties and potential applications. Since wafer scale synthesis of 2D materials is still in nascent stages, scientists cannot fully rely on traditional semiconductor techniques for related research. Delicate processes from locating the materials to electrode definition need to be well controlled. In this article, a universal fabrication protocol required in manufacturing nanoscale electronics, such as 2D quasi-heterojunction bipolar transistors (Q-HBT), and 2D back-gated transistors are demonstrated. This protocol includes the determination of material position, electron beam lithography (EBL), metal electrode definition, et al. A step by step narrative of the fabrication procedures for these devices are also presented. Furthermore, results show that each of the fabricated devices has achieved high performance with high repeatability. This work reveals a comprehensive description of process flow for preparing 2D nano-electronics, enables the research groups to access this information, and pave the way toward future electronics.

The article aims to introduce a standard and reliable fabrication procedure for the development of future low dimensional nanoelectronics.

二次元ナノエレクトロニクスを作製する標準および信頼性の高いメソッド

Two-dimensional (2D) materials have attracted huge attention due to their unique properties and potential applications. Since wafer scale synthesis of 2D ...

Fabrication of Schottky Diodes on Zn-polar BeMgZnO/ZnO Heterostructure Grown by Plasma-assisted Molecular Beam Epitaxy

Heterostructure field effect transistors (HFETs) utilizing a two dimensional electron gas (2DEG) channel have a great potential for high speed device applications. Zinc oxide (ZnO), a semiconductor with a wide bandgap (3.4 eV) and high electron saturation velocity has gained a great deal of attention as an attractive material for high speed devices. Efficient gate modulation, however, requires high-quality Schottky contacts on the barrier layer. In this article, we present our Schottky diode fabrication procedure on Zn-polar BeMgZnO/ZnO heterostructure with high density 2DEG which is achieved through strain modulation and incorporation of a few percent Be into the MgZnO-based barrier during growth by molecular beam epitaxy (MBE). To achieve high crystalline quality, nearly lattice-matched high-resistivity GaN templates grown by metal-organic chemical vapor deposition (MOCVD) are used as the substrate for the subsequent MBE growth of the oxide layers. To obtain the requisite Zn-polarity, careful surface treatment of GaN templates and control over the VI/II ratio during the growth of low temperature ZnO nucleation layer are utilized. Ti/Au electrodes serve as Ohmic contacts, and Ag electrodes deposited on the O2 plasma pretreated BeMgZnO surface are used for Schottky contacts.

Attainment of high-quality Schottky contacts is imperative for achieving efficient gate modulation in heterostructure field effect transistors (HFETs). We present the fabrication methodology and characteristics of Schottky diodes on Zn-polar BeMgZnO/ZnO heterostructures with high-density two dimensional electron gas (2DEG), grown by plasma-assisted molecular beam epitaxy on GaN templates.

プラズマ援用分子線エピタキシー法により成長した Zn 極性 ZnO/BeMgZnO へテロ構造をショットキー ダイオードの作製

Heterostructure field effect transistors (HFETs) utilizing a two dimensional electron gas (2DEG) channel have a great potential for high speed device ...

Growth of Gold Dendritic Nanoforests on Titanium Nitride-coated Silicon Substrates

In this study, a high-power impulse magnetron sputtering system is used to coat a flat and firm titanium nitride (TiN) film on silicon (Si) wafers, and a fluoride-assisted galvanic replacement reaction (FAGRR) is employed for the rapid and easy deposition of gold dendritic nanoforests (Au DNFs) on the TiN/Si substrates. Scanning electron microscopy (SEM) images and energy-dispersive X-ray spectroscopy patterns of TiN/Si and Au DNFs/TiN/Si samples validate that the synthesis process is accurately controlled. Under the reaction conditions in this study, the thickness of the Au DNFs increases linearly to 5.10 &#177; 0.20 &#181;m within 15 min of the reaction. Therefore, the employed synthesis procedure is a simple and rapid approach for preparing Au DNFs/TiN/Si composites.

This study presents a feasible procedure for synthesizing gold dendritic nanoforests on titanium nitride/silicon substrates. The thickness of gold dendritic nanoforests increases linearly within 15 min of a synthesis reaction.

窒化チタン被覆シリコン基板上の金樹状 Nanoforests の成長

In this study, a high-power impulse magnetron sputtering system is used to coat a flat and firm titanium nitride (TiN) film on silicon (Si) wafers, and a ...

Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations

Computational tools based on density-functional theory (DFT) enable the exploration of the qualitatively new, experimentally attainable nanoscale compounds for a targeted application. Theoretical simulations provide a profound understanding of the intrinsic electronic properties of functional materials. The goal of this protocol is to search for photocatalyst candidates by computational dissection. Photocatalytic applications require suitable band gaps, appropriate band edge positions relative to the redox potentials. Hybrid functionals can provide accurate values of these properties but are computationally expensive, whereas the results at the Perdew-Burke-Ernzerhof (PBE) functional level could be effective for suggesting strategies for band structure engineering via electric field and tensile strain aiming to enhance the photocatalytic performance. To illustrate this, in the present manuscript, the DFT based simulation tool VASP is used to investigate the band alignment of nanocomposites in combinations of nanotubes and nanoribbons in the ground state. To address the lifetime of photogenerated holes and electrons in the excited state, nonadiabatic dynamics calculations are needed.

Calculations performed by the Vienna Ab initio Simulation Package can be used to identify the intrinsic electronic properties of nanoscale materials and predict the potential water-splitting photocatalysts.

階層型のZnO / CdSSe等ヘテロNanotreesの合成

要約

さらに動画を探す

この動画の章

電荷分離ナノ結晶とその固体の手段によって太陽エネルギーを収穫

のCdSe / CdSのロッドやテトラポッドナノ結晶のシードの合成

任意の基板上の垂直配向小分子有機ナノワイヤーの超高密度アレイ

複合酸化物薄膜のエピタキシャル成長のために原子的に定義されたテンプレート

予熱水熱を利用したピエゾ電気NanogeneratorためのZnOナノロッド/グラフェン/ ZnOのナノロッドエピタキシャルダブルヘテロ構造の作製

整列垂直方向に配向 ZnO ナノロッド配列と反転小さな分子の太陽電池の応用

二次元ナノエレクトロニクスを作製する標準および信頼性の高いメソッド

プラズマ援用分子線エピタキシー法により成長した Zn 極性 ZnO/BeMgZnO へテロ構造をショットキーダイオードの作製

窒化チタン被覆シリコン基板上の金樹状 Nanoforests の成長

第一原理計算を用いた1次元ヴァンデルワールヘテロ構造におけるプローブタイプIIバンドアライメント

階層型のZnO / CdSSe等ヘテロNanotreesの合成

要約

さらに動画を探す

この動画の章

電荷分離ナノ結晶とその固体の手段によって太陽エネルギーを収穫

のCdSe / CdSのロッドやテトラポッドナノ結晶のシードの合成

任意の基板上の垂直配向小分子有機ナノワイヤーの超高密度アレイ

複合酸化物薄膜のエピタキシャル成長のために原子的に定義されたテンプレート

予熱水熱を利用したピエゾ電気NanogeneratorためのZnOナノロッド/グラフェン/ ZnOのナノロッドエピタキシャルダブルヘテロ構造の作製

整列垂直方向に配向 ZnO ナノロッド配列と反転小さな分子の太陽電池の応用

二次元ナノエレクトロニクスを作製する標準および信頼性の高いメソッド

プラズマ援用分子線エピタキシー法により成長した Zn 極性 ZnO/BeMgZnO へテロ構造をショットキー ダイオードの作製

窒化チタン被覆シリコン基板上の金樹状 Nanoforests の成長

第一原理計算を用いた1次元ヴァンデルワールヘテロ構造におけるプローブタイプIIバンドアライメント

プラズマ援用分子線エピタキシー法により成長した Zn 極性 ZnO/BeMgZnO へテロ構造をショットキーダイオードの作製