First-principles kinetic modeling for solar hydrogen production

在界面上开发可持续和高效的能量转换过程是快速发展的基础能源科学领域的核心。解决这一挑战的成功程度最终将取决于人们对分子水平的理解程度。在这方面，与多相催化中相应的热过程相比，电催化或光催化转化方面的严重知识差距是惊人的。这种差异在预测性质量的现状中最为明显，即。在这两个领域基于第一原理的建模，这在很大程度上归因于与电化学环境的处理有关的多因素方法学问题，以及对由光激发电荷或外部电位驱动的表面氧化还原化学的描述。成功地解决这些复杂性将使(光)电催化的建模方法学发展到与多相催化中已经建立的类似水平，其影响甚至可能取代过去十年所看到的影响。开发相应的方法是本提案的核心目标，特别强调最终将能够实现全面微动力配方的数值有效的方法。协同结合两个参与小组的方法学专长，我们的具体目标是实施和推进隐式和混合隐式/显式溶剂化模型，以及描述固-液界面上与能量相关的过程的QM/MM方法。以开发通用方法学为明确目标，我们将以水分解制氢的应用为例说明它们的应用。解开电子应答器的纠缠。光催化效应相对于相应的暗反应，这既涉及铂等金属电极上的析氢反应，也涉及二氧化钛等氧化物光催化剂上的直接水分解反应。通过这一点，我们期望达成详细的机理理解，最终形成光驱动或电势驱动的氧化还原过程的综合微观动力学模型。用动力学蒙特卡罗模拟对这些模型进行评估，将明确识别决定速率和产生过电位的步骤，从而为整个过程的合理优化提供基础。因此，我们的研究将提供一个关键的例子，说明在基础能源科学的计算方法方面的系统方法发展如何导致突破性进展，并为基础理解和前沿应用服务。

The development of sustainable and efficient energy conversion processes at interfaces is at the center of the rapidly growing field of basic energy science. How successful this challenge can be addressed will ultimately depend on the acquired degree of molecular-level understanding. In this respect, the severe knowledge gap in electro- or photocatalytic conversions compared to corresponding thermal processes in heterogeneous catalysis is staggering. This discrepancy is most blatant in the present status of predictive-quality, viz. first-principles based modelling in the two fields, which largely owes to multifactorial methodological issues connected with the treatment of the electrochemical environment and the description of the surface redox chemistry driven by the photo-excited charges or external potentials.Successfully tackling these complexities will advance modelling methodology in (photo)electrocatalysis to a similar level as already established in heterogeneous catalysis, with an impact that likely even supersedes the one seen there in the last decade. A corresponding method development is the core objective of the present proposal, with particular emphasis on numerically efficient approaches that will ultimately allow to reach comprehensive microkinetic formulations. Synergistically combining the methodological expertise of the two participating groups we specifically aim to implement and advance implicit and mixed implicit/explicit solvation models, as well as QM/MM approaches to describe energy-related processes at solid-liquid interfaces. With the clear objective to develop general-purpose methodology we will illustrate their use with applications to hydrogen generation through water splitting. Disentangling the electro- resp. photocatalytic effect with respect to the corresponding dark reaction, this concerns both the hydrogen evolution reaction at metal electrodes like Pt and direct water splitting at oxide photocatalysts like TiO2. Through this we expect to arrive at a detailed mechanistic understanding that will culminate in the formulation of comprehensive microkinetic models of the light- or potential-driven redox process. Evaluating these models with kinetic Monte Carlo simulations will unambiguously identify the rate-determining and overpotential-creating steps and therewith provide the basis for a rational optimization of the overall process. As such our study will provide a key example of how systematic method development in computational approaches to basic energy sciences leads to breakthrough progress and serves both fundamental understanding and cutting-edge application.