We report a new Ce-rich family of active oxygen evolution reaction (OER) catalysts composed of earth abundant elements, discovered using high-throughput methods. High resolution inkjet printing was used to produce 5456 discrete oxide compositions containing the elements nickel, iron, cobalt and cerium. The catalytic performance of each of these compositions was measured under conditions applicable to distributed solar fuels generation using a three-electrode scanning drop electrochemical cell. The catalytic activity and stability of representative compositions (Ni_(0.5)Fe_(0.3)Co_(0.17)Ce_(0.03)O_x and Ni_(0.3)Fe^(0.07)Co_(0.2)Ce_(0.43)O_x) from 2 distinct regions were verified by resynthesizing these compositions on glassy carbon rods for electrochemical testing. The activity of the new Ce-rich catalysts was further verified using an unrelated synthetic method to electrodeposit a pseudo-ternary composition Ni_(0.2)Co_(0.3)Ce_(0.5)O_x, which produced a catalyst with 10 mA cm^(−2) oxygen evolution current at 310 mV overpotential. The unique Tafel behavior of these Ce-rich catalysts affords the opportunity for further improvement.
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机译:我们报告了一个新的富含铈的活性氧释放反应(OER)催化剂家族,该催化剂由富含地球的元素组成,使用高通量方法发现。高分辨率喷墨印刷用于生产5456种离散的氧化物组合物,其中包含镍,铁,钴和铈。在适用于使用三电极扫描滴电化学电池的分布式太阳能燃料产生的条件下测量这些组合物中的每一种的催化性能。来自两个不同区域的代表性成分(Ni_(0.5)Fe_(0.3)Co_(0.17)Ce_(0.03)O_x和Ni_(0.3)Fe ^(0.07)Co_(0.2)Ce_(0.43)O_x的催化活性和稳定性)通过在玻璃碳棒上重新合成这些组合物进行电化学测试来验证。使用不相关的合成方法进一步电沉积伪三元组成Ni_(0.2)Co_(0.3)Ce_(0.5)O_x进一步验证了新型富Ce催化剂的活性,生成了10 mA cm ^(-2)的催化剂)310 mV过电位时的氧气析出电流。这些富含铈的催化剂的独特的Tafel行为为进一步改进提供了机会。
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