這個全新太陽能裝置被稱為光電化學電池，它將鹵化物鈣鈦礦半導體與電催化劑集成在一個單一、可擴展的裝置中，利用太陽能將水分解成氫氣和氧氣

該裝置的一個關鍵創新是使用抗腐蝕屏障，保護廉價的鹵化物鈣鈦礦半導體不受水的損害，同時不妨礙電子的傳遞，克服了以前水不穩定性的挑戰

這一突破性技術在將太陽能轉化為電力的化學反應中具有廣泛的應用潛力，可將原料轉化為燃料，利用太陽能收集的電力

據油價網7月29日報道，萊斯大學的工程師們已經創造了一種“將陽光轉化為氫氣”的裝置，其效率創下了歷史新高。該裝置將新一代的鹵化物鈣鈦礦半導體與電催化劑集成在一個耐用、成本效益高且可擴展的裝置中。這項技術有望成為氫氣技術的新標準。事實上，該裝置是一個以太陽能驅動的水分解電池。

根據發表在《自然通訊》雜志上的一項研究，該裝置實現了20.8％的太陽能轉化效率，而且這項研究結果目前并不需要付費即可訪問。

這項新技術對清潔能源來說是向前一大步的突破，可以在一個平臺用太陽能收集的電力將原料轉化為燃料。

化學與生物分子工程師阿迪蒂亞·莫希特（Aditya Mohite）領導的實驗室使用了一種防腐蝕屏障，將半導體與水隔離開來，而不會阻礙電子的傳遞。

該研究的主要作者之一，化學與生物分子工程博士生奧斯汀·費爾（Austin Fehr）評論說：“能否將陽光作為制造化學品的能源來源是清潔能源經濟的最大障礙之一。我們的目標是構建經濟可行的平臺，能夠產生太陽能源衍生燃料。在這里，我們設計了一個能夠吸收光并在其表面完成電化學水分解化學反應的系統。”

該裝置被稱為光電化學電池，因為光的吸收、其轉化為電力以及使用電力來驅動化學反應都在同一裝置中進行。到目前為止，利用光電化學技術生產綠氫的效率較低，并且半導體成本較高。

費爾補充說：“所有這種類型的裝置都是利用太陽能和水產生綠氫的，但我們的裝置之所以特別，是因為它具有突破歷史新高的效率，并且使用的半導體非常便宜。”

莫希特實驗室及其合作者通過將競爭激烈的太陽能電池轉變為反應器，利用收集的能量將水分解為氧氣和氫氣。他們需要克服的挑戰是鹵化物鈣鈦礦在水中極不穩定，而用于隔離半導體的涂層最終要么破壞其功能，要么損壞它們。

邁克爾·王（Michael Wong）是萊斯大學的化學工程師，也是該研究的合著者之一，他指出：“在過去的兩年里，我們不斷嘗試不同的材料和技術。”在經過漫長的試驗后未能得到預期結果后，研究人員最終找到了一個成功的解決方案。

費爾說：“我們的關鍵是需要兩層屏障，一層用于阻擋水，另一層用于在鈣鈦礦層和保護層之間建立良好的電氣接觸。”“我們的結果是光電化學電池在沒有太陽能聚焦的情況下具有最高效率，并且對于使用鹵化物鈣鈦礦半導體的電池整體效果最好。”

費爾說：“對于這個歷來由價格昂貴半導體主導的領域來說，這是第一次取得這樣的成果，可能代表了這類裝置首次實現商業可行性的途徑。”

研究人員展示了他們的屏障設計在不同反應和不同半導體上的工作情況，使其適用于許多系統。

莫希特說：“我們希望這樣的系統能成為一個平臺，利用豐富的原料和太陽光作為能源輸入，驅動各種電子轉化為燃料反應。”

費爾補充說：“隨著穩定性和規模的進一步改進，這項技術可能會開啟氫能經濟，并改變人類從化石燃料制造物品的方式，轉向太陽能燃料。”

這項工作充滿了樂觀情緒。然而，我們需要記住，一塊頂級的太陽能收集器在一天中最佳情況下只能接收到每平方米約100瓦的電力。人們的疑惑是：在一個小眾市場上，免費的氫氣會有多大用處。

這項技術還處于起步階段。它能走多遠還有待進一步的研究和工程化改進。但即使在20.8%的太陽能驅動水分解效率下，還有很長的路要走。

該研究的主要作者包括萊斯大學的研究生阿尤什·阿格拉瓦爾（Ayush Agrawal）和法茲·曼達尼（Faiz Mandani），以及美國國家可再生能源實驗室的部分作者。該實驗室是由可持續能源聯盟（Alliance for Sustainable Energy LLC）為美國國家能源部運營的，合同號為DE-AC36-08GO28308。

胡耀東 譯自 油價網

原文如下：

Green Hydrogen Gets Greener With Record-Breaking Solar Device

The solar device, known as a photoelectrochemical cell, integrates halide perovskite semiconductors with electrocatalysts in a single, scalable device that can split water into hydrogen and oxygen using solar energy.

A key innovation of the device is the use of an anti-corrosion barrier that protects the cheap halide perovskite semiconductor from water, without hindering the transfer of electrons, overcoming previous challenges with water instability.

The breakthrough technology could have broad applications in driving chemical reactions that convert feedstocks into fuels using solar-harvested electricity.

Rice University engineers have created a device that “turns sunlight into hydrogen” with record-breaking efficiency. The device integrates next-generation halide perovskite semiconductors with electrocatalysts in a single, durable, cost-effective and scalable device. The press release believes the engineers have set a new standard for hydrogen technology. The device is factually a solar driven water splitting cell.

According to a study published in Nature Communications, the device achieved a 20.8% solar-to-hydrogen conversion efficiency. Today the study is not behind a paywall.

The new technology is a significant step forward for clean energy and could serve as a platform for a wide range of chemical reactions that use solar-harvested electricity to convert feedstocks into fuels.

The lab of chemical and biomolecular engineer Aditya Mohite built the integrated photoreactor using an anticorrosion barrier that insulates the semiconductor from water without impeding the transfer of electrons.

Austin Fehr, a chemical and biomolecular engineering doctoral student and one of the study’s lead authors commented, “Using sunlight as an energy source to manufacture chemicals is one of the largest hurdles to a clean energy economy. Our goal is to build economically feasible platforms that can generate solar-derived fuels. Here, we designed a system that absorbs light and completes electrochemical water-splitting chemistry on its surface.”

The device is known as a photoelectrochemical cell because the absorption of light, its conversion into electricity and the use of the electricity to power a chemical reaction all occur in the same device. Until now, using photoelectrochemical technology to produce green hydrogen was hampered by low efficiencies and the high cost of semiconductors.

“All devices of this type produce green hydrogen using only sunlight and water, but ours is exceptional because it has record-breaking efficiency and it uses a semiconductor that is very cheap,” Fehr added.

The Mohite lab and its collaborators created the device by turning their highly-competitive solar cell into a reactor that could use harvested energy to split water into oxygen and hydrogen. The challenge they had to overcome was that halide perovskites are extremely unstable in water and coatings used to insulate the semiconductors ended up either disrupting their function or damaging them.

Michael Wong, a Rice chemical engineer and co-author on the study noted, “Over the last two years, we’ve gone back and forth trying different materials and techniques.” After lengthy trials failed to yield the desired result, the researchers finally came across a winning solution.

“Our key insight was that you needed two layers to the barrier, one to block the water and one to make good electrical contact between the perovskite layers and the protective layer,” Fehr said. “Our results are the highest efficiency for photoelectrochemical cells without solar concentration, and the best overall for those using halide perovskite semiconductors.

“It is a first for a field that has historically been dominated by prohibitively expensive semiconductors, and may represent a pathway to commercial feasibility for this type of device for the first time ever,” Fehr said.

The researchers showed their barrier design worked for different reactions and with different semiconductors, making it applicable across many systems.

Mohite said, “We hope that such systems will serve as a platform for driving a wide range of electrons to fuel-forming reactions using abundant feedstocks with only sunlight as the energy input.”

“With further improvements to stability and scale, this technology could open up the hydrogen economy and change the way humans make things from fossil fuel to solar fuel,” Fehr added.

There is a great deal of optimism in this work. Yet we need to remember that a top of the line solar collector at best of day is only going to see about 100 watts of power incoming per square meter. One has to ask just how useful is free hydrogen going to be in a niche market.

The technology is very much at its beginning. How far it can go is yet to be researched and engineered out somewhat more. But even at 20.8% solar driven water splitting efficiency there is a very long way to go.

Rice graduate students Ayush Agrawal and Faiz Mandani are lead authors on the study alongside Fehr. The work was also authored in part by the National Renewable Energy Laboratory, which is operated by Alliance for Sustainable Energy LLC for the Department of Energy under Contract DE-AC36-08GO28308.