富含矿物质的生物质多孔水热炭在环境应用中的功能导向设计不可避免地受到碳-灰顽固性的影响。然而，调控并解耦原始碳骨架与灰分的方法尚不明确，这限制了水热炭的应用。在此，我们提出了一种利用可调相态熔融碳酸盐打破碳-灰耦合水热炭刚性结构的简便策略。本研究以畜禽粪污和NaHCO₃制备活化水热炭，并将NH₃作为目标污染物进行案例分析。研究发现，由于高温下的氧化还原效应，炭中的有机组分可致Na₂CO₃的熔点显著地下降，至800 °C以下。随着热强度的增加，含钠的活性组分有效地打破了碳与灰分的耦合作用，并将大量无机成分转化为可溶解态，从而重新构建了富含分层通道和活性缺陷边缘的水热炭骨架。表面极性和介孔分布共同控制了多循环过程中NH₃吸附衰减，五次最大总吸附容量为100.49 mg·g^-1。综合光谱表征和理论计算表明，碳表面上NH₃分子的引入促进了电子向化学吸附氧的迁移，进而导致吡啶-N的氧化。本研究深入探讨了水热炭的结构与功能相关性，为源自高灰分生物质的水热炭的合理设计提供了新思路。

The function-led design of porous hydrochar from mineral-rich biowaste for environmental applications inevitably suffers from carbon-ash recalcitrance. However, a method to alter the original carbon skeleton with ash remains elusive and hinders the availability of hydrochar. Herein, we propose a facile strategy for breaking the rigid structure of carbon-ash coupled hydrochar using phase-tunable molten carbonates. A case system was designed in which livestock manure and NaHCO₃ were used to prepare the activated hydrochar, and NH₃ served as the target contaminant. Due to the redox effect, we found that organic fractions significantly advanced the melting temperature of Na₂CO₃ below 800 °C. The Na species steadily broke the carbon-ash interaction as the thermal intensity increased and transformed inorganic constituents to facilitate ash dissolution, rebuilding the hydrochar skeleton with abundant hierarchical channels and active defect edges. The surface polarity and mesopore distribution collectively governed the five cycles NH₃ adsorption attenuation process. Manure hydrochar delivered favorable potential for application with a maximum overall adsorption capacity of 100.49 mg·g⁻¹. Integrated spectroscopic characterization and theoretical computations revealed that incorporating NH₃ on the carbon surface could transfer electrons to chemisorbed oxygen, which promoted the oxidation of pyridine-N during adsorption. This work offers deep insight into the structure function correlation of hydrochar and inspires a more rational design of engineered hydrochar from high-ash biowaste.