這個(gè)全新太陽能裝置被稱為光電化學(xué)電池，它將鹵化物鈣鈦礦半導(dǎo)體與電催化劑集成在一個(gè)單一、可擴(kuò)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(gè)關(guān)鍵創(chuàng)新是使用抗腐蝕屏障，保護(hù)廉價(jià)的鹵化物鈣鈦礦半導(dǎo)體不受水的損害，同時(shí)不妨礙電子的傳遞，克服了以前水不穩(wěn)定性的挑戰(zhàn)

這一突破性技術(shù)在將太陽能轉(zhuǎn)化為電力的化學(xué)反應(yīng)中具有廣泛的應(yīng)用潛力，可將原料轉(zhuǎn)化為燃料，利用太陽能收集的電力

據(jù)油價(jià)網(wǎng)7月29日報(bào)道，萊斯大學(xué)的工程師們已經(jīng)創(chuàng)造了一種“將陽光轉(zhuǎn)化為氫氣”的裝置，其效率創(chuàng)下了歷史新高。該裝置將新一代的鹵化物鈣鈦礦半導(dǎo)體與電催化劑集成在一個(gè)耐用、成本效益高且可擴(kuò)展的裝置中。這項(xiàng)技術(shù)有望成為氫氣技術(shù)的新標(biāo)準(zhǔn)。事實(shí)上，該裝置是一個(gè)以太陽能驅(qū)動(dòng)的水分解電池。

根據(jù)發(fā)表在《自然通訊》雜志上的一項(xiàng)研究，該裝置實(shí)現(xiàn)了20.8％的太陽能轉(zhuǎn)化效率，而且這項(xiàng)研究結(jié)果目前并不需要付費(fèi)即可訪問。

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

化學(xué)與生物分子工程師阿迪蒂亞·莫希特（Aditya Mohite）領(lǐng)導(dǎo)的實(shí)驗(yàn)室使用了一種防腐蝕屏障，將半導(dǎo)體與水隔離開來，而不會(huì)阻礙電子的傳遞。

該研究的主要作者之一，化學(xué)與生物分子工程博士生奧斯汀·費(fèi)爾（Austin Fehr）評論說：“能否將陽光作為制造化學(xué)品的能源來源是清潔能源經(jīng)濟(jì)的最大障礙之一。我們的目標(biāo)是構(gòu)建經(jīng)濟(jì)可行的平臺，能夠產(chǎn)生太陽能源衍生燃料。在這里，我們設(shè)計(jì)了一個(gè)能夠吸收光并在其表面完成電化學(xué)水分解化學(xué)反應(yīng)的系統(tǒng)?！?/p>

該裝置被稱為光電化學(xué)電池，因?yàn)楣獾奈铡⑵滢D(zhuǎn)化為電力以及使用電力來驅(qū)動(dòng)化學(xué)反應(yīng)都在同一裝置中進(jìn)行。到目前為止，利用光電化學(xué)技術(shù)生產(chǎn)綠氫的效率較低，并且半導(dǎo)體成本較高。

費(fèi)爾補(bǔ)充說：“所有這種類型的裝置都是利用太陽能和水產(chǎn)生綠氫的，但我們的裝置之所以特別，是因?yàn)樗哂型黄茪v史新高的效率，并且使用的半導(dǎo)體非常便宜?！?/p>

莫希特實(shí)驗(yàn)室及其合作者通過將競爭激烈的太陽能電池轉(zhuǎn)變?yōu)榉磻?yīng)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(zhàn)是鹵化物鈣鈦礦在水中極不穩(wěn)定，而用于隔離半導(dǎo)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(xué)的化學(xué)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(shù)?！痹诮?jīng)過漫長的試驗(yàn)后未能得到預(yù)期結(jié)果后，研究人員最終找到了一個(gè)成功的解決方案。

費(fèi)爾說：“我們的關(guān)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(hù)層之間建立良好的電氣接觸?！薄拔覀兊慕Y(jié)果是光電化學(xué)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(dǎo)體的電池整體效果最好。”

費(fèi)爾說：“對于這個(gè)歷來由價(jià)格昂貴半導(dǎo)體主導(dǎo)的領(lǐng)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(shí)現(xiàn)商業(yè)可行性的途徑?！?/p>

研究人員展示了他們的屏障設(shè)計(jì)在不同反應(yīng)和不同半導(dǎo)體上的工作情況，使其適用于許多系統(tǒng)。

莫希特說：“我們希望這樣的系統(tǒng)能成為一個(gè)平臺，利用豐富的原料和太陽光作為能源輸入，驅(qū)動(dòng)各種電子轉(zhuǎn)化為燃料反應(yīng)?！?/p>

費(fèi)爾補(bǔ)充說：“隨著穩(wěn)定性和規(guī)模的進(jìn)一步改進(jìn)，這項(xiàng)技術(shù)可能會(huì)開啟氫能經(jīng)濟(jì)，并改變?nèi)祟悘幕剂现圃煳锲返姆绞?，轉(zhuǎn)向太陽能燃料?！?/p>

這項(xiàng)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(gè)小眾市場上，免費(fèi)的氫氣會(huì)有多大用處。

這項(xiàng)技術(shù)還處于起步階段。它能走多遠(yuǎn)還有待進(jìn)一步的研究和工程化改進(jìn)。但即使在20.8%的太陽能驅(qū)動(dòng)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(xué)的研究生阿尤什·阿格拉瓦爾（Ayush Agrawal）和法茲·曼達(dá)尼（Faiz Mandani），以及美國國家可再生能源實(shí)驗(yàn)室的部分作者。該實(shí)驗(yàn)室是由可持續(xù)能源聯(lián)盟（Alliance for Sustainable Energy LLC）為美國國家能源部運(yùn)營的，合同號為DE-AC36-08GO28308。

胡耀東 譯自 油價(jià)網(wǎng)

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.